An In-Depth Clinical Review of Pre-Ovulatory Vaginal Bleeding

Introduction: Understanding Bleeding in the Follicular Phase

The experience of vaginal bleeding outside of an expected menstrual period can be a source of significant concern.

This symptom, known clinically as intermenstrual bleeding (IMB) or as a form of abnormal uterine bleeding (AUB), warrants careful consideration and understanding.¹

When such bleeding occurs specifically in the days leading up to ovulation, it falls within the follicular phase of the menstrual cycle.

The follicular phase commences on the first day of menstruation and culminates with the release of an egg from the ovary, a process known as ovulation.⁴

This period is defined by a complex and dynamic interplay of hormones aimed at preparing the body for potential pregnancy.

Bleeding that occurs before ovulation represents a spectrum of causality, ranging from a benign physiological event to a manifestation of an underlying medical condition.¹

On one end of this spectrum is “ovulation spotting,” a light bleeding event directly related to the hormonal shifts that trigger the release of an e.g. While this is considered a normal physiological phenomenon, it is a relatively uncommon experience.

Clinical data suggest that only a small fraction of menstruating individuals, estimated to be around 5%, experience this type of mid-cycle spotting.⁹

This apparent paradox—that an event can be physiologically “normal” yet statistically “uncommon”—is a crucial nuance.

In a medical context, “normal” signifies that the process is not inherently pathological or indicative of disease.

The low prevalence suggests that while the hormonal fluctuations associated with ovulation are universal, the endometrial response to these changes varies significantly among individuals.

This variation underscores the importance of a comprehensive evaluation.

Because it is not a universally shared experience, bleeding before ovulation should not be automatically dismissed as benign.

It necessitates a thorough understanding of the normal mechanism while also prompting a careful review of other potential causes.

This report provides an exhaustive clinical examination of pre-ovulatory bleeding, beginning with the physiology of ovulation spotting and proceeding through a systematic differential diagnosis of other structural, hormonal, infectious, and iatrogenic causes.

It will conclude with a detailed overview of the diagnostic pathway and guidance on when to seek medical consultation, empowering individuals with the knowledge to navigate this symptom effectively.

Section 1: The Physiology of the Menstrual Cycle and Ovulation-Related Spotting

To comprehend why bleeding may occur before ovulation, it is essential to first understand the intricate hormonal orchestration of the menstrual cycle’s follicular phase.

This phase is not a static period but a dynamic process of preparation culminating in the release of a mature e.g.

1.1 The Hormonal Architecture of the Follicular Phase

The menstrual cycle is governed by the hypothalamic-pituitary-ovarian (HPO) axis, a sophisticated communication network involving the brain and the ovaries.¹

The process begins in the hypothalamus, a region of the brain that releases Gonadotropin-Releasing Hormone (GnRH) in a pulsatile manner.

This GnRH signal prompts the nearby pituitary gland to secrete two key hormones: Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH).⁴

The follicular phase officially starts on the first day of menstrual bleeding.⁴

During this time, FSH stimulates the growth and development of a group, or cohort, of small fluid-filled sacs in the ovaries called follicles, each containing an immature e.g.⁶

As the days progress, one of these follicles becomes the “dominant follicle,” outgrowing the others, which then regress.⁴

The cells within this developing dominant follicle, specifically the granulosa cells, begin to produce increasing amounts of the hormone estrogen, primarily in the form of 17-β estradiol.⁴

This rising tide of estrogen has two primary effects.

First, it acts on the lining of the uterus, the endometrium, causing it to thicken and proliferate in preparation for a potential pregnancy.

This is why the follicular phase is sometimes called the proliferative phase.⁴

Second, estrogen sends feedback signals to the pituitary gland.

Initially, it provides negative feedback to suppress further FSH secretion, a mechanism that ensures only the single dominant follicle continues to mature.⁴

However, once estrogen levels reach a critical peak and are sustained for a period, this feedback switches from negative to positive.

This switch triggers a massive, rapid surge of LH from the pituitary gland.

It is this LH surge that serves as the ultimate hormonal trigger for ovulation, causing the mature egg to be released from the dominant follicle approximately 24 to 36 hours later.⁴

1.2 Mechanisms of Physiological Mid-Cycle Spotting

The precise hormonal events that trigger ovulation are also responsible for the phenomenon of physiological ovulation spotting.

This benign bleeding is believed to occur through two primary mechanisms.

1.2.1 Estrogen Withdrawal Bleeding

The most widely accepted cause of ovulation spotting is a rapid fluctuation in hormone levels.

In the days leading up to ovulation, estrogen levels rise steadily to their peak.

This high level of estrogen is responsible for maintaining the stability of the newly thickened endometrium.

Immediately following the LH surge and just prior to the actual release of the egg, there is a sharp and sudden drop in estrogen levels.¹⁷

Progesterone, the hormone that will take over to stabilize the endometrium in the second half of the cycle (the luteal phase), has not yet risen sufficiently to compensate.

This brief hormonal gap can cause a temporary destabilization of the uterine lining, leading to a small amount of shedding and light bleeding.⁸

This specific phenomenon is often referred to as “estrogen breakthrough bleeding” or “estrogen withdrawal bleeding”.¹⁷

The fact that this event is experienced by only a small percentage of individuals, despite the hormonal pattern being universal in ovulatory cycles, points toward differences in individual physiology.

The bleeding is likely not caused by the estrogen dip alone, but rather by the endometrium’s unique sensitivity to that hormonal shift.

Individuals who experience ovulation spotting may have an endometrial lining that is more sensitive to hormonal fluctuations, or they may experience a more profound or rapid drop in estrogen, or a slightly delayed rise in progesterone, creating a brief window of instability sufficient to cause minor bleeding.

This explains why an event rooted in normal physiology is not experienced by everyone and highlights the importance of individual biological variation.

1.2.2 Follicle Rupture

A secondary, and likely less significant, proposed mechanism involves the physical act of ovulation itself.

To release the mature egg, the dominant follicle on the surface of the ovary must rupture.

It is theorized that this rupture can cause a minuscule amount of blood or follicular fluid to be released into the abdominal cavity.¹²

This fluid can act as a mild irritant to the peritoneum, the sensitive membrane lining the abdomen, leading to the characteristic one-sided mid-cycle pain known as

Mittelschmerz (German for “middle pain”).¹⁴

It is plausible that this minimal bleeding could also manifest as very light vaginal spotting.²³

1.3 Clinical Presentation of Ovulation Spotting

Benign ovulation spotting has a distinct clinical profile that helps differentiate it from other types of bleeding.

Its characteristics are closely tied to the physiological events of ovulation.

• Timing: True ovulation spotting occurs predictably in the middle of the menstrual cycle, generally between days 12 and 16 of a standard 28-day cycle, or approximately 14 days before the onset of the next period.¹⁵ The bleeding may occur immediately before, during, or just after the actual release of the egg, coinciding with the LH surge.⁹
• Volume and Appearance: The bleeding is characteristically very light and is almost always described as “spotting” rather than a true flow. It typically involves only a few drops of blood, noticeable on toilet paper or as a small stain on underwear, and does not require the use of a pad or tampon.¹ The color of the blood can vary. It may appear as light pink or bright red if the fresh blood mixes with the abundant cervical mucus present at this time, or it can be brown or dark red, indicating older blood that has taken longer to be expelled.¹²
• Duration: The episode is transient and short-lived, typically lasting for only one to two days at most.⁸
• Associated Symptoms: A key diagnostic clue is the presence of other concurrent signs of ovulation. These physiological markers help confirm that the spotting is related to the fertile window. They include:

• Mittelschmerz: A distinct, one-sided pain in the lower abdomen, corresponding to the ovary that is releasing an egg. The pain can be described as a dull ache or a sharp twinge and may last from a few minutes to 48 hours.¹²
• Cervical Mucus Changes: A noticeable increase in vaginal discharge that becomes clear, slippery, and stretchy, often compared to the consistency of raw egg whites. This change facilitates sperm motility.⁹
• Basal Body Temperature (BBT) Shift: For those tracking BBT, a slight dip in temperature may be observed just before ovulation, followed by a clear and sustained rise of approximately 0.5 to 1.0 degree Fahrenheit after ovulation, driven by the increase in progesterone.¹⁵
• Fertility Implications: Far from being a negative sign, ovulation spotting is considered an indicator of peak fertility. It signals that the body is undergoing the process of releasing an egg, marking the most fertile time in the menstrual cycle for conception to occur.¹¹

Section 2: Differential Diagnosis: A Systematic Review of Intermenstrual Bleeding Causes

While physiological ovulation spotting is a benign cause of bleeding before ovulation, it is crucial to recognize that it is just one of many possibilities.

Any instance of intermenstrual bleeding warrants a broader consideration of potential causes to ensure that no underlying pathology is overlooked.

The PALM-COEIN system, an acronym developed by the International Federation of Gynecology and Obstetrics (FIGO), provides a standardized and comprehensive framework for classifying the causes of abnormal uterine bleeding.²⁵

This system categorizes etiologies into structural (PALM) and non-structural (COEIN) groups.

A central concept that unifies nearly all causes of intermenstrual bleeding is the principle of endometrial stability.

The uterine lining requires a precise, balanced, and sustained hormonal and structural environment to remain intact between menstrual periods.

Any factor that disrupts this delicate equilibrium—be it a sudden hormonal shift, a physical distortion, or an inflammatory process—can compromise the integrity of the endometrium and lead to unscheduled bleeding.

This framework helps to understand the “why” behind the various conditions discussed below.

2.1 Structural Pathologies (The PALM Group)

These are causes related to physical abnormalities of the uterus that can be identified through imaging or biopsy.

2.1.1 P – Polyps (Endometrial and Cervical)

• Description: Polyps are benign (noncancerous) growths that arise from the glandular tissue lining the inside of the uterus (endometrial polyps) or the canal of the cervix (cervical polyps).¹ These growths, which can range from the size of a sesame seed to a golf ball, are often influenced by estrogen levels and are more common as women age, peaking in their 40s.²⁷
• Bleeding Pattern: Polyps are a classic cause of intermenstrual bleeding and spotting.²⁶ The bleeding occurs because the polyps themselves have a fragile blood supply that can easily be disrupted, leading to irregular bleeding at any point in the cycle.²⁶ They can also contribute to heavy menstrual periods (menorrhagia).²⁹
• Diagnosis: The diagnosis is often suspected based on the symptom of irregular bleeding and is confirmed through imaging. A transvaginal ultrasound is a common first step, but its accuracy is significantly enhanced by saline infusion sonohysterography (SIS), where saline is introduced into the uterus to provide a clearer view of the cavity.²⁹ The gold standard for both diagnosis and treatment is hysteroscopy, a procedure where a thin, lighted camera is inserted into the uterus, allowing for direct visualization and removal of the polyp.²⁸

2.1.2 A – Adenomyosis

• Description: Adenomyosis is a condition in which the tissue that normally lines the uterus (the endometrium) grows into the muscular wall of the uterus (the myometrium).²⁵ This misplaced tissue continues to behave as it normally would—thickening, breaking down, and bleeding during each menstrual cycle—but within the muscle wall.
• Bleeding Pattern: The primary symptoms of adenomyosis are typically very heavy, prolonged, and painful menstrual periods.²⁵ However, it can also be a cause of bleeding between periods. The presence of this tissue within the muscle disrupts the uterus’s ability to contract effectively and can create an unstable uterine environment.

2.1.3 L – Leiomyomas (Uterine Fibroids)

• Description: Uterine fibroids, also known as leiomyomas, are extremely common benign tumors arising from the smooth muscle tissue of the uterus.³⁵ Their growth is stimulated by the hormones estrogen and progesterone.³⁵ They are classified by their location: submucosal fibroids project into the uterine cavity, intramural fibroids are within the uterine wall, and subserosal fibroids grow on the outside of the uterus.³⁵
• Bleeding Pattern: Fibroids are a leading cause of abnormal uterine bleeding. While they are most famously associated with heavy and prolonged periods, they are also a frequent cause of bleeding between periods.³⁶ Submucosal fibroids, in particular, are notorious for causing intermenstrual spotting because they directly distort the uterine cavity and the endometrial lining, creating an unstable surface with abnormal blood vessels that are prone to bleeding.²⁶
• Diagnosis: Fibroids may be suspected during a pelvic exam if the uterus feels enlarged or irregularly shaped. The preferred initial diagnostic tool is a transvaginal ultrasound, which is highly sensitive for detecting fibroids.³¹

2.1.4 M – Malignancy and Hyperplasia

• Description: This category includes endometrial hyperplasia, a precancerous condition involving excessive thickening of the uterine lining, and cancers of the reproductive organs, most notably endometrial (uterine) and cervical cancer.¹⁷
• Context and Bleeding Pattern: It is critical to emphasize that cancer is an uncommon cause of intermenstrual bleeding in premenopausal women.³ However, the risk is not zero and increases with specific risk factors, including obesity, a history of polycystic ovary syndrome (PCOS) with chronic anovulation (which leads to prolonged unopposed estrogen exposure), and a family history of certain cancers.³⁴ Any bleeding after menopause is considered a significant red flag and must be investigated to rule out malignancy.³⁴

2.2 Non-Structural Pathologies (The COEIN Group)

These are causes not related to a physical abnormality of the uterus but rather to systemic conditions, hormonal imbalances, or external factors.

2.2.1 C – Coagulopathy

• Description: Coagulopathies are bleeding disorders, either inherited (like von Willebrand disease) or acquired, that impair the body’s ability to form blood clots effectively.²⁵
• Bleeding Pattern: The classic presentation is heavy menstrual bleeding that begins with the first period (menarche). However, these disorders can also contribute to or exacerbate bleeding between periods.²⁵ Other signs, such as easy bruising, frequent nosebleeds, or prolonged bleeding after minor cuts, can suggest an underlying bleeding disorder.³³

2.2.2 O – Ovulatory Dysfunction

• Description: This is a broad and very common category of AUB where the root cause is irregular or absent ovulation (anovulation).⁴¹ In a normal cycle, ovulation is followed by the formation of the corpus luteum, which produces progesterone. Progesterone’s role is to stabilize the estrogen-primed endometrium. When ovulation does not occur, the endometrium is exposed to continuous estrogen stimulation without the balancing effect of progesterone. This leads to an excessively thick, fragile, and unstable uterine lining that eventually breaks down and sheds in an unpredictable, often heavy, and prolonged manner.³⁴
• Key Causes of Ovulatory Dysfunction:

• Polycystic Ovary Syndrome (PCOS): PCOS is a common endocrine disorder characterized by a hormonal imbalance, including high levels of androgens (male hormones) and insulin resistance.⁴³ This imbalance disrupts the HPO axis and leads to chronic anovulation.⁵⁰ Irregular menstrual bleeding is a hallmark symptom of PCOS. Cycles may be infrequent (oligomenorrhea) or absent (amenorrhea), interspersed with episodes of unpredictable and often heavy bleeding.⁵⁰
• Thyroid Disease: The thyroid gland plays a crucial role in regulating metabolism and the menstrual cycle. Both an underactive thyroid (hypothyroidism) and an overactive thyroid (hyperthyroidism) can interfere with the HPO axis, disrupt ovulation, and cause a wide range of menstrual irregularities, including spotting between periods, heavy flow, or absent periods.¹⁷
• Lifestyle-Induced Dysregulation: The sensitive HPO axis can be disrupted by significant external stressors.

• Chronic Stress: High levels of psychological or physical stress trigger the release of the hormone cortisol. Elevated cortisol can suppress the normal pulsatile release of GnRH from the hypothalamus, thereby disrupting the entire downstream hormonal cascade necessary for ovulation. This can lead to irregular cycles and spotting.¹
• Excessive Exercise, Diet, and Weight Changes: The body requires a certain level of energy availability to maintain reproductive function. Extreme physical training, restrictive diets, or significant and rapid weight loss or gain can signal to the hypothalamus that it is not an optimal time for reproduction, leading to ovulatory dysfunction (hypothalamic amenorrhea) and irregular bleeding.¹

2.2.3 E – Endometrial and Cervical Causes

• Infections:

• Pelvic Inflammatory Disease (PID): PID is a serious infection of the upper female reproductive organs, including the uterus, fallopian tubes, and ovaries.⁶⁴ It is most often caused by sexually transmitted infections (STIs), particularly chlamydia and gonorrhea, that ascend from the lower genital tract.⁶⁶ The resulting inflammation makes the tissues of the endometrium and cervix fragile (friable) and prone to bleeding, which can manifest as spotting between periods or bleeding after intercourse.⁶⁴
• Cervicitis and Vaginitis: Localized inflammation of the cervix (cervicitis) or vagina (vaginitis) can also cause spotting. These conditions can be caused by STIs like chlamydia, gonorrhea, or trichomoniasis, or by other non-sexually transmitted infections like bacterial vaginosis or yeast infections.¹⁷
• Cervical Ectropion: Also known as cervical eversion, this is a benign condition where the soft, glandular cells that line the inside of the cervical canal are present on the outer surface of the cervix.⁷⁰ These cells are more delicate and have a richer blood supply than the normal squamous cells on the cervix’s exterior. Consequently, they can bleed very easily with contact, such as during sexual intercourse or even a Pap smear, leading to spotting. This condition is particularly common in younger women, pregnant women, and those using combined oral contraceptives, as it is influenced by higher estrogen levels.⁷⁰

2.2.4 I – Iatrogenic

• Description: Iatrogenic causes are those resulting from medical treatment or intervention.
• Hormonal Contraception: This is one of the most frequent causes of intermenstrual spotting, commonly known as “breakthrough bleeding”.⁷ It is particularly common during the first three to six months of starting a new hormonal method as the body adjusts.⁷⁴ The mechanism involves the hormonal contraceptive creating an endometrium that is different from a natural cycle. Low-dose estrogen pills or progestin-only methods (like the mini-pill, contraceptive implant, or hormonal IUD) tend to create a thin, somewhat atrophic, and fragile uterine lining that is prone to unscheduled, light shedding.⁷⁵ Missing pills or taking them inconsistently can also trigger breakthrough bleeding by causing sudden hormonal fluctuations.⁸
• Other Medications: Certain medications can cause abnormal bleeding. Anticoagulants (blood thinners) like warfarin or aspirin can interfere with normal clotting and lead to spotting or heavier flow.⁷ Fertility drugs, which are designed to manipulate the HPO axis to induce ovulation, can also cause spotting as a side effect of the significant hormonal shifts they create.¹⁷

2.2.5 N – Not Yet Classified

• Pregnancy-Related Bleeding: While pregnancy is a post-ovulatory event, it is a critical consideration in any case of abnormal bleeding. It is crucial to distinguish the timing.

• Implantation Bleeding: This occurs when a fertilized egg burrows into the uterine lining. It is a luteal phase event, happening approximately 6 to 12 days after ovulation, which corresponds to about one to two weeks before a period is due.⁸ It is typically very light, pink or brown, and lasts for a couple of days.
• Ectopic Pregnancy: This is a medical emergency where a fertilized egg implants outside the uterus, most commonly in a fallopian tube.⁷ It can present with irregular spotting or bleeding, often accompanied by abdominal or pelvic pain and dizziness. Any sexually active individual with abnormal bleeding and pain should be evaluated to rule out this life-threatening condition.⁷⁹

Section 3: Interpreting the Clinical Signs

For an individual experiencing bleeding before ovulation, paying close attention to the specific characteristics of the bleeding can provide valuable clues to its potential origin.

This information, when relayed to a healthcare provider, can significantly aid in the diagnostic process.

3.1 The Significance of Color and Consistency

The appearance of vaginal bleeding is largely determined by its age and its mixture with other normal secretions.

The color and consistency can offer hints about the source and nature of the bleeding.

• Bright Red: This color indicates fresh blood that has been expelled from the body relatively quickly.⁸⁰ It signifies an active, steady bleed. Bright red spotting can be consistent with physiological ovulation spotting, where minor endometrial shedding occurs, or it could originate from a more accessible source like a cervical polyp, cervical ectropion, or an infection causing cervical friability.⁸¹
• Pink: Pink spotting is typically the result of fresh blood mixing with clear cervical mucus.⁷⁹ This dilution gives it a lighter, pinkish hue. This is very common with ovulation spotting, as it occurs when cervical mucus is typically abundant and watery.¹² Pink spotting can also be associated with low-estrogen states or be an early sign of implantation bleeding.⁷⁹
• Brown or Dark Red: These darker shades are indicative of older blood that has had time to oxidize before leaving the body.⁷⁹ The iron in the blood reacts with oxygen, causing it to darken. Brown spotting is common and can be seen with ovulation spotting, implantation bleeding, or as the very beginning or end of a menstrual period when flow is slow.¹⁵
• Watery or Mixed with Mucus: A thin, watery consistency, or blood that is clearly mixed with normal vaginal or cervical discharge, is characteristic of spotting rather than a true menstrual flow.⁸⁴ This suggests a smaller volume of blood is being diluted by other fluids.
• Gray, Green, or Yellowish with Odor: The presence of these colors, especially when accompanied by a foul or fishy odor, is a strong indicator of an infection.¹² Gray discharge may suggest bacterial vaginosis, while yellow or green discharge can be a sign of an STI like trichomoniasis, chlamydia, or gonorrhea, or a more advanced infection like Pelvic Inflammatory Disease (PID).⁶⁴

3.2 Comparative Analysis of Common Bleeding Events

One of the greatest challenges in self-assessment is distinguishing between different types of bleeding that can occur around the mid-cycle point.

The timing, volume, and associated symptoms are key differentiators.

The following table provides a direct comparison of the most common bleeding events to aid in clarification.

Feature	Ovulation Spotting	Implantation Bleeding	Menstrual Period	Postcoital Bleeding
Timing in Cycle	Mid-cycle, typically 13-20 days into the cycle and ~14 days before the next period.15	Post-ovulatory (luteal phase), typically 6-12 days after ovulation, or about a week before the expected period.8	Begins the menstrual cycle (Day 1). Occurs cyclically every 21-35 days.2	Immediately during or after sexual intercourse, independent of cycle day.3
Volume	Very light spotting; a few drops, not requiring a pad or tampon.1	Very light spotting to light bleeding.1	Light to heavy flow requiring menstrual products; average loss is 5-80 mL.1	Can range from very light spotting to more significant bleeding, depending on the cause.86
Color	Light pink, bright red, or brown.12	Typically pink or brown.1	Bright red at peak flow, darkening to brown or black at the beginning and end.1	Usually bright red or pink, as it is typically fresh bleeding from trauma or a friable lesion.72
Duration	Short-lived; typically lasts 1-2 days.8	Brief; typically lasts from a few hours to 1-3 days.8	Lasts 3-8 days.1	Usually brief, lasting from a few hours to a day, but can persist if the underlying cause is not addressed.70
Associated Symptoms	May be accompanied by Mittelschmerz (one-sided pelvic twinge), increased “egg white” cervical mucus, or a shift in basal body temperature.9	May be accompanied by very early pregnancy symptoms such as mild cramping, fatigue, or breast tenderness.24	Often preceded by Premenstrual Syndrome (PMS) symptoms; accompanied by menstrual cramps, bloating, and fatigue.5	May be associated with pain during intercourse (dyspareunia) or may be painless. The presence of other symptoms depends on the underlying cause (e.g., discharge with infection).64

Section 4: The Clinical Evaluation Pathway

While self-assessment and tracking are valuable, any new, persistent, or concerning bleeding between periods necessitates a professional medical evaluation.

A systematic diagnostic process is essential to accurately identify the cause and ensure appropriate management.

Understanding this process can reduce anxiety and facilitate a more productive partnership between an individual and their healthcare provider.

4.1 Red Flags: When to Seek Medical Consultation

Certain signs and symptoms associated with intermenstrual bleeding warrant more immediate medical attention.

It is important to distinguish between situations requiring urgent versus prompt consultation.

• Seek Urgent Medical Care (e.g., emergency department or immediate appointment) for:

• Heavy Bleeding: Bleeding that soaks through one or more pads or tampons per hour for two or more consecutive hours.⁹
• Severe Pelvic Pain: Sharp, severe, or persistent pain in the abdomen or pelvis, especially if it comes on suddenly.¹
• Signs of Hemodynamic Instability: Dizziness, lightheadedness, fainting, or extreme fatigue, which could indicate significant blood loss and anemia.³⁸
• Signs of Severe Infection: A high fever, chills, or a foul-smelling vaginal discharge accompanying the bleeding.⁶⁴
• Schedule a Prompt Consultation with a gynecologist or primary care provider for:

• Any Postmenopausal Bleeding: Vaginal bleeding of any amount after menopause is never considered normal and must be evaluated to rule out endometrial cancer.⁹
• Persistent or Worsening Bleeding: Spotting or bleeding between periods that occurs for more than two to three consecutive cycles or becomes progressively heavier over time.¹²
• Bleeding After Intercourse (Postcoital Bleeding): This symptom should always be evaluated, as it can be a sign of cervical issues, including infection, polyps, or, rarely, cancer.⁹
• Bleeding Accompanied by Other Concerning Symptoms: Such as unexplained weight changes, changes in bowel or bladder habits, or new or worsening pelvic pressure.³⁶

For any other new or unexplained intermenstrual bleeding, it is advisable to schedule a routine appointment to discuss the symptoms and ensure a correct diagnosis.⁷

4.2 The Diagnostic Workflow: From Consultation to Diagnosis

The clinical evaluation for pre-ovulatory bleeding is a systematic process that moves from general history-taking to more specific and, if necessary, invasive testing.

This logical progression ensures that the diagnosis is reached efficiently and accurately.

The process is not a random battery of tests but a structured investigation where each step informs the next.

It begins with a thorough conversation and physical exam, which often provides enough information to narrow down the potential causes significantly.

Basic lab tests then rule out common and critical conditions like pregnancy and infection.

Based on these initial findings, the investigation may proceed to hormonal analysis or structural imaging, each chosen to test a specific hypothesis generated from the earlier steps.

This methodical approach is the cornerstone of modern gynecological practice, designed to provide clarity while minimizing unnecessary procedures.

The following table outlines the typical diagnostic workflow.

Phase	Component / Test	Purpose and Rationale
Phase 1: Initial Office Visit & History	Detailed Medical & Menstrual History	To establish the character of the bleeding (timing, duration, volume, color, triggers) and identify risk factors. The provider will ask about cycle regularity, contraceptive use, sexual history, medications, and systemic symptoms (e.g., pain, fatigue, acne, hair growth) to begin forming a differential diagnosis.2
	Physical & Pelvic Examination	A general physical exam checks for signs of systemic disease (e.g., thyroid nodules, signs of PCOS). A pelvic exam, including a speculum and bimanual exam, allows for visual inspection of the vagina and cervix for lesions, polyps, or signs of infection, and to assess the size, shape, and tenderness of the uterus and ovaries.31
Phase 2: Foundational Laboratory Testing	Pregnancy Test (Urine or Serum hCG)	To definitively rule out pregnancy, including ectopic pregnancy, which is a common cause of abnormal bleeding in reproductive-aged individuals.31
	Complete Blood Count (CBC)	To assess for anemia (low hemoglobin/hematocrit) resulting from chronic or heavy blood loss and to check platelet counts, which could indicate a bleeding disorder.93
	Cervical Cancer Screening (Pap Smear) & STI Testing	A Pap smear is performed if one is not up-to-date to screen for cervical cell abnormalities. Swabs are taken to test for common infections like chlamydia and gonorrhea, as cervicitis is a frequent cause of spotting.2
Phase 3: Hormonal & Systemic Evaluation (If Indicated)	Thyroid-Stimulating Hormone (TSH) & Prolactin Levels	To screen for thyroid dysfunction and hyperprolactinemia, two common endocrine disorders that disrupt ovulation and cause irregular bleeding. These are often tested if no obvious structural cause is found.31
	Androgen Levels (e.g., Testosterone, DHEAS)	Measured if PCOS is suspected based on symptoms like irregular periods, acne, or hirsutism (excess hair growth).94
	Coagulation Studies (e.g., PT, PTT, von Willebrand factor)	Ordered if a bleeding disorder is suspected based on a personal or family history of easy bruising, bleeding from other sites, or heavy menstrual bleeding since menarche.42
Phase 4: Structural Imaging & Direct Visualization	Transvaginal Ultrasound	This is the primary imaging modality used to visualize the pelvic organs. It is highly effective for identifying structural abnormalities such as uterine fibroids, ovarian cysts, and thickening of the endometrial lining.31
	Saline Infusion Sonohysterography (SIS)	An enhanced ultrasound where sterile saline is infused into the uterine cavity. This separates the uterine walls, providing a much clearer view of the endometrium and making it the best non-invasive test for detecting small, intracavitary lesions like endometrial polyps or submucosal fibroids.29
	Hysteroscopy	A procedure where a thin, lighted camera (hysteroscope) is inserted through the cervix into the uterus. It allows for direct visualization of the entire uterine cavity. It is the gold standard for diagnosing and simultaneously treating (removing) lesions like polyps and small fibroids.28
	Endometrial Biopsy	A procedure to obtain a small sample of tissue from the uterine lining. The sample is examined under a microscope to rule out endometrial hyperplasia or cancer. It is typically performed in cases of persistent abnormal bleeding, thickened endometrium on ultrasound, or in individuals with risk factors for endometrial cancer.29

Section 5: Management Approaches and Concluding Recommendations

The management of pre-ovulatory bleeding is fundamentally dependent on its underlying cause, the severity of the symptoms, the individual’s age, and their future fertility desires.²

Treatment is not always necessary, but when it is, it is tailored to address the specific diagnosis derived from the clinical evaluation.

5.1 Overview of Management Strategies

• Expectant Management: For benign, minimal, and asymptomatic ovulation spotting that has been confirmed after ruling out other pathologies, no treatment is required. Reassurance and education are the primary management tools.²³
• Hormonal Regulation: For bleeding caused by hormonal imbalances such as ovulatory dysfunction (e.g., PCOS, stress-induced irregularities) or to manage bleeding from conditions like fibroids or adenomyosis, hormonal therapies are often the first line. These can include combined oral contraceptives, progestin-only pills, or a progestin-releasing intrauterine device (IUD), all of which work to stabilize the endometrium and regulate the cycle.¹⁹
• Antimicrobial Therapy: If the bleeding is caused by an infection, such as an STI (chlamydia, gonorrhea) or Pelvic Inflammatory Disease (PID), a course of antibiotics is the definitive treatment for both the individual and their sexual partners to resolve the infection and prevent recurrence.⁶⁴
• Surgical Intervention: For structural abnormalities that are causing significant symptoms, surgical removal may be recommended. This can range from minimally invasive procedures like a hysteroscopic polypectomy (removal of a polyp) or myomectomy (removal of a fibroid) to more definitive treatments like endometrial ablation (destruction of the uterine lining) or hysterectomy (removal of the uterus) for those who have completed childbearing and have persistent, severe symptoms.²³

5.2 Final Recommendations for the Health-Conscious Individual

Navigating the concern of unexpected bleeding requires a combination of self-awareness, knowledge, and collaboration with healthcare professionals.

The following recommendations are intended to empower individuals to manage their reproductive health proactively.

• Empowerment Through Knowledge: Understanding the wide range of potential causes for pre-ovulatory bleeding—from the physiological to the pathological—is the first and most critical step. This knowledge transforms anxiety into informed action and allows for a more nuanced understanding of one’s own body.
• The Importance of Tracking: Consistently tracking the menstrual cycle is an invaluable tool. Documenting the start and end dates of periods, along with the timing, volume, color, and duration of any intermenstrual bleeding, provides objective data that is immensely helpful to a healthcare provider in establishing a pattern and narrowing the diagnostic possibilities.¹ Noting associated symptoms such as pain, discharge, or mood changes further enriches this clinical picture.
• Lifestyle Considerations: Recognizing the profound impact of lifestyle on hormonal health is key. The HPO axis is sensitive to external factors. Proactive management of chronic stress, adherence to a balanced and nutrient-dense diet, and maintaining a moderate and consistent exercise routine can contribute significantly to hormonal balance and menstrual regularity, potentially mitigating some forms of ovulatory dysfunction.⁵⁹
• Collaborative Care: Ultimately, the most effective approach to managing reproductive health is a collaborative one. An individual should view themselves as an active partner in their own healthcare. By using the comprehensive information in this report, they can engage in a confident, informed, and productive dialogue with their gynecologist or other healthcare provider. This partnership ensures that concerns are heard, a thorough evaluation is conducted, and a management plan is developed that aligns with both clinical evidence and personal health goals.

Works cited

1. 10 Causes of Mid-Cycle Spotting | The Fertility Institute of New Orleans, accessed August 12, 2025, https://fertilityinstitute.com/10-causes-of-mid-cycle-spotting/
2. Abnormal Uterine Bleeding – StatPearls – NCBI Bookshelf, accessed August 12, 2025, https://www.ncbi.nlm.nih.gov/books/NBK532913/
3. Intermenstrual and Postcoital Bleeding | Doctor – Patient.info, accessed August 12, 2025, https://patient.info/doctor/intermenstrual-and-postcoital-bleeding
4. Physiology, Menstrual Cycle – StatPearls – NCBI Bookshelf, accessed August 12, 2025, https://www.ncbi.nlm.nih.gov/books/NBK500020/
5. The menstrual cycle | Better Health Channel, accessed August 12, 2025, https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/menstrual-cycle
6. Follicular Phase Of Menstrual Cycle: Hormone Levels & Length, accessed August 12, 2025, https://my.clevelandclinic.org/health/body/23953-follicular-phase
7. Bleeding between periods | healthdirect, accessed August 12, 2025, https://www.healthdirect.gov.au/bleeding-between-periods
8. Spotting Between Periods – Your Period, accessed August 12, 2025, https://www.yourperiod.ca/abnormal-pain-and-menstrual-bleeding/spotting-between-periods/
9. Is Ovulation Bleeding Normal? Signs of Spotting During Ovulation – Healthgrades Health Library, accessed August 12, 2025, https://resources.healthgrades.com/right-care/womens-health/ovulation-bleeding
10. www.clearblue.com, accessed August 12, 2025, https://www.clearblue.com/ovulation/understanding-ovulation-bleeding#:~:text=Bleeding%20during%20ovulation%20is%20not,and%20typically%20not%20every%20cycle.
11. Everything you need to know about ovulation bleeding – Flo, accessed August 12, 2025, https://flo.health/menstrual-cycle/health/ovulation/ovulation-bleeding
12. Is Ovulation Bleeding Normal? What You Need to Know – Hormona, accessed August 12, 2025, https://www.hormona.io/blog/is-ovulation-bleeding-normal-what-you-need-to-know/
13. The Normal Menstrual Cycle and the Control of Ovulation – Endotext – NCBI Bookshelf, accessed August 12, 2025, https://www.ncbi.nlm.nih.gov/books/NBK279054/
14. Menstrual Cycle – Women’s Health Issues – Merck Manual Consumer Version, accessed August 12, 2025, https://www.merckmanuals.com/home/women-s-health-issues/biology-of-the-female-reproductive-system/menstrual-cycle
15. Ovulation Bleeding: Causes, Symptoms & Remedies – GarbhaGudi IVF Centre, accessed August 12, 2025, https://www.garbhagudi.com/blogs/spotting-or-light-bleeding-in-between-the-periods-reasons-and-remedies
16. Ovulation bleeding and ovulation spotting: What it is, & why it happens – Clue app, accessed August 12, 2025, https://helloclue.com/articles/cycle-a-z/ovulation-bleeding-what-it-is-how-to-know-if-youre-experiencing-it
17. Ovulation bleeding: How to identify spotting between periods, accessed August 12, 2025, https://www.medicalnewstoday.com/articles/325847
18. www.medicalnewstoday.com, accessed August 12, 2025, https://www.medicalnewstoday.com/articles/325847#:~:text=Ovulation%20bleeding%20generally%20refers%20to,progesterone%20levels%20begin%20to%20increase.
19. What Is Ovulation Bleeding and How Do You Identify It? – Verywell Health, accessed August 12, 2025, https://www.verywellhealth.com/ovulation-bleeding-5182477
20. Ovulation Bleeding: Causes, Colors, and What’s Normal – Natural Cycles, accessed August 12, 2025, https://www.naturalcycles.com/cyclematters/ovulation-bleeding
21. Understanding Ovulation Bleeding: Causes, Symptoms, and Management, accessed August 12, 2025, https://shop.miracare.com/blogs/resources/ovulation-bleeding
22. Mittelschmerz – Symptoms and causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/diseases-conditions/mittelschmerz/symptoms-causes/syc-20375122
23. Ovulation Bleeding – Causes, Symptoms & Treatment Options – Narayana Health, accessed August 12, 2025, https://www.narayanahealth.org/blog/ovulation-bleeding-causes-symptoms-treatment-options
24. Ovulation Bleeding: How Serious It Can Be and How to Treat It? | Advanced OBGYN Institute, accessed August 12, 2025, https://www.toplinemd.com/advanced-obgyn-institute/ovulation-bleeding-how-serious-it-can-be-and-how-to-treat-it/
25. Abnormal Uterine Bleeding in Premenopausal Women – AAFP, accessed August 12, 2025, https://www.aafp.org/pubs/afp/issues/2019/0401/p435.html
26. Fibroids vs Polyps: Know the Difference | Dr. Len Kliman, accessed August 12, 2025, https://drlenkliman.com.au/articles/fibroids-vs-polyps-understanding-the-difference/
27. Uterine Polyps Overview – Brigham and Women’s Hospital, accessed August 12, 2025, https://www.brighamandwomens.org/medical-resources/uterine-polyps
28. Uterine Polyps | ColumbiaDoctors, accessed August 12, 2025, https://www.columbiadoctors.org/treatments-conditions/uterine-polyps
29. Uterine Polyps: Causes, Symptoms, Diagnosis & Treatment – Cleveland Clinic, accessed August 12, 2025, https://my.clevelandclinic.org/health/diseases/14683-uterine-polyps
30. Endometrial polyps: Pathogenesis, sequelae and treatment – PMC – PubMed Central, accessed August 12, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC6501471/
31. Abnormal Vaginal Bleeding – Evaluation and Treatment – Radiologyinfo.org, accessed August 12, 2025, https://www.radiologyinfo.org/en/info/vaginalbleeding
32. Abnormal Uterine Bleeding: Causes, Diagnosis & Treatment – Cleveland Clinic, accessed August 12, 2025, https://my.clevelandclinic.org/health/diseases/menometrorrhagia-abnormal-uterine-bleeding
33. Heavy Bleeding – Menomonie, Wisconsin – Mayo Clinic Health System, accessed August 12, 2025, https://www.mayoclinichealthsystem.org/locations/menomonie/services-and-treatments/obstetrics-and-gynecology/heavy-or-irregular-bleeding
34. Heavy menstrual bleeding – Symptoms and causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/diseases-conditions/menorrhagia/symptoms-causes/syc-20352829
35. Uterine Fibroids: Diagnosis and Treatment | AAFP, accessed August 12, 2025, https://www.aafp.org/pubs/afp/issues/2017/0115/p100.html
36. Uterine Fibroids: Causes, Symptoms & Treatment – Cleveland Clinic, accessed August 12, 2025, https://my.clevelandclinic.org/health/diseases/9130-uterine-fibroids
37. Fibroids | Johns Hopkins Medicine, accessed August 12, 2025, https://www.hopkinsmedicine.org/health/conditions-and-diseases/uterine-fibroids
38. Uterine fibroids – Symptoms and causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/diseases-conditions/uterine-fibroids/symptoms-causes/syc-20354288
39. Uterine Fibroids Symptoms – Northwestern Medicine, accessed August 12, 2025, https://www.nm.org/conditions-and-care-areas/womens-health/obgyn/gynecology/uterine-fibroids/symptoms
40. Intermenstrual bleeding – Wikipedia, accessed August 12, 2025, https://en.wikipedia.org/wiki/Intermenstrual_bleeding
41. Evaluation and Management of Abnormal Uterine Bleeding in Premenopausal Women, accessed August 12, 2025, https://www.aafp.org/pubs/afp/issues/2012/0101/p35.html
42. Approach to diagnosis and management of abnormal uterine bleeding – PMC, accessed August 12, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC1952557/
43. Polycystic Ovary Syndrome (PCOS) – Women’s Health Issues – Merck Manuals, accessed August 12, 2025, https://www.merckmanuals.com/home/women-s-health-issues/menstrual-disorders-and-abnormal-vaginal-bleeding/polycystic-ovary-syndrome-pcos
44. Vaginal bleeding Causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/symptoms/vaginal-bleeding/basics/causes/sym-20050756
45. Abnormal Uterine Bleeding – Yale Medicine, accessed August 12, 2025, https://www.yalemedicine.org/conditions/abnormal-uterine-bleeding
46. Vaginal or uterine bleeding: MedlinePlus Medical Encyclopedia, accessed August 12, 2025, https://medlineplus.gov/ency/article/007496.htm
47. Vaginal bleeding – hormonal Information | Mount Sinai – New York, accessed August 12, 2025, https://www.mountsinai.org/health-library/diseases-conditions/vaginal-bleeding-hormonal
48. Polycystic ovary syndrome (PCOS) – Symptoms and causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/diseases-conditions/pcos/symptoms-causes/syc-20353439
49. PCOS (Polycystic Ovary Syndrome): Symptoms & Treatment, accessed August 12, 2025, https://my.clevelandclinic.org/health/diseases/8316-polycystic-ovary-syndrome-pcos
50. my.clevelandclinic.org, accessed August 12, 2025, https://my.clevelandclinic.org/health/diseases/8316-polycystic-ovary-syndrome-pcos#:~:text=The%20most%20common%20signs%20and,involve%20heavy%20bleeding%20during%20periods.
51. Polycystic Ovary Syndrome (PCOS) – Johns Hopkins Medicine, accessed August 12, 2025, https://www.hopkinsmedicine.org/health/conditions-and-diseases/polycystic-ovary-syndrome-pcos
52. Why Women With PCOS Have Irregular Periods – Verywell Health, accessed August 12, 2025, https://www.verywellhealth.com/why-do-women-with-pcos-have-irregular-periods-2616650
53. Options for Managing Periods with PCOS | Children’s Hospital Colorado, accessed August 12, 2025, https://www.childrenscolorado.org/globalassets/departments/gynecology/informational-pdfs/options-for-managing-periods-with-pcos.pdf?v=490a55
54. A PATIENT’S GUIDE: Polycystic Ovary Syndrome (PCOS) – PMC, accessed August 12, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC5393469/
55. What Are Periods Like When You Have PCOS? – Nurture Gynaecology, accessed August 12, 2025, https://nurturegynaecology.com.au/what-are-periods-like-when-you-have-pcos/
56. womenshealth.gov, accessed August 12, 2025, https://womenshealth.gov/a-z-topics/thyroid-disease#:~:text=Too%20much%20or%20too%20little%20thyroid%20hormone%20can%20make%20your,your%20ovaries%2C%20may%20be%20involved.
57. Thyroid Disorders in Women | Johns Hopkins Medicine, accessed August 12, 2025, https://www.hopkinsmedicine.org/health/conditions-and-diseases/thyroid-disorders-in-women
58. Stress Can Cause Spotting: Identification, Treatment, Prevention – Healthline, accessed August 12, 2025, https://www.healthline.com/health/can-stress-cause-spotting
59. Can Stress Cause Spotting Between Periods? – GoodRx, accessed August 12, 2025, https://www.goodrx.com/health-topic/womens-health/can-stress-cause-spotting
60. How Does Stress Impact Your Period? – Healthline, accessed August 12, 2025, https://www.healthline.com/health/stress/can-stress-mess-up-your-period
61. The Link Between Stress and Your Periods – Women’s Health Services, accessed August 12, 2025, https://www.womenshealthservices.com/blog/the-link-between-stress-and-your-periods
62. Influence of medical conditions and lifestyle factors on the menstrual cycle – PubMed, accessed August 12, 2025, https://pubmed.ncbi.nlm.nih.gov/12410008/
63. Menstrual cycles and the impact upon performance in elite British track and field athletes: a longitudinal study – Frontiers, accessed August 12, 2025, https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2024.1296189/full
64. Pelvic inflammatory disease – NHS, accessed August 12, 2025, https://www.nhs.uk/conditions/pelvic-inflammatory-disease-pid/
65. Pelvic Inflammatory Disease – StatPearls – NCBI Bookshelf, accessed August 12, 2025, https://www.ncbi.nlm.nih.gov/books/NBK499959/
66. Pelvic Inflammatory Disease (PID) – Women’s Health Issues – Merck Manuals, accessed August 12, 2025, https://www.merckmanuals.com/home/women-s-health-issues/vaginitis-cervicitis-and-pelvic-inflammatory-disease/pelvic-inflammatory-disease-pid
67. Pelvic inflammatory disease (PID) – Symptoms & causes – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/diseases-conditions/pelvic-inflammatory-disease/symptoms-causes/syc-20352594
68. medlineplus.gov, accessed August 12, 2025, https://medlineplus.gov/ency/article/003156.htm#:~:text=Changes%20in%20hormone%20levels,use%20(may%20cause%20occasional%20spotting)
69. Postcoital bleeding – Cheshire Gynaecologist, accessed August 12, 2025, https://www.cheshiregynaecologist.co.uk/treatments-procedures/postcoital-bleeding/
70. Cervical Ectopy (Cervical Erosion), accessed August 12, 2025, https://mft.nhs.uk/app/uploads/sites/4/2018/04/18-28-Cervical-Ectopy-June-2018.pdf
71. Patient Information Cervical Ectropion – East and North Hertfordshire NHS Trust, accessed August 12, 2025, https://www.enherts-tr.nhs.uk/wp-content/uploads/2020/11/Cervical-Ectropion-v1-10.2020.pdf
72. Bleeding During Ovulation | Causes And What It Might Mean, accessed August 12, 2025, https://tidewaterobgyn.com/bleeding-during-ovulation/
73. Cervical Ectropion | CUH – Cambridge University Hospitals, accessed August 12, 2025, https://www.cuh.nhs.uk/patient-information/cervical-ectropion/
74. Birth Control and Spotting: What to Know – WebMD, accessed August 12, 2025, https://www.webmd.com/sex/birth-control/birth-control-spotting
75. Breakthrough Bleeding from Birth Control and How to Stop It – Healthline, accessed August 12, 2025, https://www.healthline.com/health/womens-health/breakthrough-bleeding-on-the-pill
76. Contraceptive Pearl: Irregular Bleeding with Hormonal Contraception, accessed August 12, 2025, https://www.reproductiveaccess.org/resource/contraceptive-pearl-irregular-bleeding-with-hormonal-contraception/
77. www.mayoclinic.org, accessed August 12, 2025, https://www.mayoclinic.org/tests-procedures/combination-birth-control-pills/expert-answers/seasonale-side-effects/faq-20058109#:~:text=The%20cause%20of%20breakthrough%20bleeding,the%20uterus%20to%20become%20thinner.
78. Extended-cycle birth control pills: Is spotting common? – Mayo Clinic, accessed August 12, 2025, https://www.mayoclinic.org/tests-procedures/combination-birth-control-pills/expert-answers/seasonale-side-effects/faq-20058109
79. Brown Vaginal Discharge: Causes, Treatment, When to Worry – Healthline, accessed August 12, 2025, https://www.healthline.com/health/brown-vaginal-discharge
80. What does the color of period blood mean? – Medical News Today, accessed August 12, 2025, https://www.medicalnewstoday.com/articles/324848
81. Period Blood Color Chart: Black, Brown, Bright Red, and More – Healthline, accessed August 12, 2025, https://www.healthline.com/health/period-blood
82. Period Blood Colors and What They Mean – Verywell Health, accessed August 12, 2025, https://www.verywellhealth.com/what-does-menstrual-blood-look-like-2721937
83. What Does Ovulation Bleeding & Spotting Mean for Your Health? – Dr. Laura Nicholas, accessed August 12, 2025, https://www.drlauranicholas.com/blog/2021/05/06/ovulation-spotting
84. Spotting vs. Period: Differences, Symptoms, Causes, & Treatments – MedicineNet, accessed August 12, 2025, https://www.medicinenet.com/spotting_vs_period_differences/article.htm
85. What Does Spotting Look Like? Menstruation, Implantation, Pregnancy – Healthline, accessed August 12, 2025, https://www.healthline.com/health/womens-health/what-does-spotting-look-like
86. Spotting vs. period: Differences and common causes – Medical News Today, accessed August 12, 2025, https://www.medicalnewstoday.com/articles/317595
87. Bleeding After Sex: What You Need to Know – WebMD, accessed August 12, 2025, https://www.webmd.com/women/bleeding-after-sex
88. Postcoital Bleeding (Bleeding After Sex) and Its Causes – Verywell Health, accessed August 12, 2025, https://www.verywellhealth.com/postcoital-bleeding-3947657
89. Vaginal bleeding between periods: MedlinePlus Medical Encyclopedia, accessed August 12, 2025, https://medlineplus.gov/ency/article/003156.htm
90. 5 Conditions That Cause Vaginal Bleeding – North Naples Gynecology and Obstetrics, accessed August 12, 2025, https://www.northnaplesobgyn.com/blog/5-conditions-that-cause-vaginal-bleeding
91. Investigating and managing abnormal vaginal bleeding: an overview – bpacnz, accessed August 12, 2025, https://bpac.org.nz/2019/bleeding.aspx
92. Abnormal Uterine Bleeding: Diagnosis & Treatment | NewYork-Presbyterian, accessed August 12, 2025, https://www.nyp.org/womens/general-gynecology/abnormal-uterine-bleeding/treatment
93. emedicine.medscape.com, accessed August 12, 2025, https://emedicine.medscape.com/article/257007-workup#:~:text=Workup-,Laboratory%20Studies,other%20hormone%20assays%20as%20indicated.
94. Abnormal Uterine Bleeding – Gynecology and Obstetrics – Merck Manuals, accessed August 12, 2025, https://www.merckmanuals.com/professional/gynecology-and-obstetrics/menstrual-abnormalities/abnormal-uterine-bleeding
95. Vaginal Bleeding: Causes, Diagnosis & What It Means – Cleveland Clinic, accessed August 12, 2025, https://my.clevelandclinic.org/health/symptoms/17899-vaginal-bleeding
96. Uterine Polyp Symptoms and Treatment – Brigham and Women’s Hospital, accessed August 12, 2025, https://www.brighamandwomens.org/obgyn/resources/uterine-polyps
97. Cycle syncing: Choosing food and diet for hormonal balance – Baylor Scott & White Health, accessed August 12, 2025, https://www.bswhealth.com/blog/cycle-syncing-choosing-food-and-diet-for-hormonal-balance
98. Cycle Syncing Nutrition and Exercise – Cleveland Clinic Health Essentials, accessed August 12, 2025, https://health.clevelandclinic.org/nutrition-and-exercise-throughout-your-menstrual-cycle