How to manage irregular menstrual cycles and ovulation?

Managing Irregular Menstrual Cycles and Mid-Cycle Bleeding

If you are experiencing bleeding between periods or during ovulation, first rule out pregnancy, sexually transmitted infections, and structural uterine problems before starting any treatment. 1

Immediate Diagnostic Steps

Rule out pregnancy first with a beta-hCG test in all reproductive-age women with abnormal bleeding patterns, regardless of reported contraceptive use. 1, 2, 3

Essential Laboratory Evaluation

Obtain the following tests to identify underlying causes:

• Pregnancy test (mandatory first step) 1, 2, 3
• STI screening (gonorrhea, chlamydia) as infections alter bleeding patterns 1, 2
• TSH and prolactin levels between cycle days 3-6, as thyroid dysfunction and hyperprolactinemia commonly cause irregular bleeding 1, 2
• LH, FSH, and testosterone between cycle days 3-6 if PCOS is suspected (LH/FSH ratio >2 suggests PCOS; testosterone >2.5 nmol/L suggests PCOS) 1
• Mid-luteal progesterone (<6 nmol/L indicates anovulation) 1

Structural Evaluation

Perform transvaginal ultrasonography to exclude endometrial polyps, submucosal fibroids, adenomyosis, or other pathologic uterine conditions, particularly in women over 35 years. 1, 2, 3

Treatment Algorithm Based on Findings

If No Underlying Pathology Found

For irregular bleeding without heavy flow:

• First-line treatment: Mefenamic acid 500 mg three times daily for 5 days, or celecoxib 200 mg daily for 5 days 1, 3
• These NSAIDs reduce bleeding through prostaglandin inhibition 1

For heavy or prolonged irregular bleeding:

• Short-term treatment: Low-dose combined oral contraceptives for 10-20 days 1, 3
• Important caveat: Combined hormonal contraceptives increase venous thromboembolism risk three to fourfold 1, 3

For long-term management when estrogen is contraindicated:

• Gold standard: Levonorgestrel-releasing IUD (20 μg/day) reduces menstrual blood loss by 71-95% 1, 3

If Scanty Mid-Cycle Bleeding Only

Provide reassurance that scanty menstruation or mid-cycle spotting does not require treatment if no underlying pathology is found. 2

Critical Considerations for Fertility Awareness

If you are using calendar-based or symptom-based fertility awareness methods:

• Irregular vaginal bleeding makes these methods unreliable and should prompt delay of use until bleeding patterns normalize 4
• Barrier methods should be recommended until the bleeding pattern is compatible with proper fertility awareness method use 4
• The condition should be evaluated and treated as necessary before relying on fertility awareness methods 4

Special Population Considerations

For athletes: Consider Relative Energy Deficiency in Sport (RED-S) as an underlying cause, and assess for low energy availability, eating disorders, and bone health concerns. 3

For women with epilepsy: Higher rates of PCOS (10-25% vs 4-6% in general population) may require specialized management. 1

Follow-Up Strategy

Reassess within 2-3 cycles to evaluate treatment response. 3

If bleeding persists despite initial treatment:

• Consider alternative hormonal methods or adjust current regimen 1, 3
• Reassess for missed structural or endocrine pathology 3
• Refer to gynecology if bleeding continues despite two treatment attempts 3

Common Pitfalls to Avoid

Never assume functional changes without excluding structural pathology, especially in women over 35 where polyps and fibroids become more common. 2

Do not initiate hormonal treatment for scanty mid-cycle bleeding alone without ruling out pathology, as minimal bleeding is generally benign. 2

Enhanced counseling about expected bleeding patterns before initiating any hormonal treatment significantly reduces method discontinuation rates. 1, 3

If using progestin-only pills (POPs): Irregular menstrual patterns are common and expected; 22% of users experience amenorrhea and 34% experience infrequent spotting, which is normal. 4, 5