What is the most appropriate first‑line oral contraceptive for a pre‑menopausal woman with heavy abnormal uterine bleeding?

Best Oral Contraceptive for Heavy Abnormal Uterine Bleeding

A monophasic combined oral contraceptive containing 30–35 μg ethinyl estradiol with levonorgestrel or norgestimate is the recommended first-line oral contraceptive for heavy menstrual bleeding in premenopausal women. 1

First-Line Oral Contraceptive Selection

• Prescribe a monophasic COC with 30–35 μg ethinyl estradiol combined with either levonorgestrel or norgestimate as the initial therapy, as these formulations decrease menstrual blood loss by inducing regular shedding of a thinner endometrium and reduce cramping. 1

• Monophasic formulations are preferred over multiphasic pills because they provide consistent hormone levels throughout the cycle, which better stabilizes the endometrium and controls bleeding. 1

• The 30–35 μg ethinyl estradiol dose range is optimal—lower doses (20 μg) may result in more breakthrough bleeding, while this dose provides effective bleeding control with acceptable side effects. 1

Alternative Oral Contraceptive Options

• Estradiol valerate/dienogest (E2V/DNG) is a newer alternative that has demonstrated a 65% reduction in mean menstrual blood loss after six months of use, with approximately half of women achieving an 80% reduction. 2

• E2V/DNG may theoretically have fewer adverse effects on lipid and glucose metabolism compared to ethinyl estradiol-based COCs, though clinical trials have not yet confirmed reduced thromboembolic risk, so assume a similar safety profile to other COCs containing ≤35 μg ethinyl estradiol. 2

Dosing Strategy for Acute Heavy Bleeding

• For acute heavy bleeding requiring rapid control, initiate the COC immediately (same-day start) regardless of cycle phase, with no need to wait for menses. 1

• No backup contraception is required if the COC is started within the first 5 days of menstrual bleeding; if started after day 5, use barrier contraception for 7 days. 1

• After bleeding is controlled, continue the COC for at least 21 consecutive days before any hormone-free interval to prevent recurrent bleeding. 1

Managing Persistent or Breakthrough Bleeding

• If breakthrough bleeding occurs on standard cyclic COCs, add ibuprofen 400–600 mg three times daily for 5–7 days as first-line adjunctive therapy. 1, 3

• Before treating breakthrough bleeding, rule out pregnancy, sexually transmitted infections, new uterine pathology (polyps, fibroids), and medication interactions (particularly with anticonvulsants or antibiotics that may reduce COC efficacy). 1

• If bleeding persists despite standard-dose COCs plus NSAIDs, consider increasing the estrogen content from 20 μg to 35 μg daily or switching to an extended/continuous regimen. 4

Extended/Continuous Regimens for Refractory Cases

• Extended regimens (taking active pills continuously for 3–4 months followed by a 4–7 day hormone-free interval) are particularly useful for women with severe bleeding, anemia, or dysmenorrhea. 1

• Counsel patients that unscheduled spotting during the first 3–6 months of extended use is common, not harmful, and typically decreases with continued use—this does not indicate method failure. 1

• If breakthrough bleeding becomes problematic during extended use, allow a 3–4 day hormone-free interval (but not during the first 21 days of use and not more than once per month). 1

Critical Contraindications and Safety Screening

• Screen for cardiovascular risk factors, particularly in perimenopausal women, as COCs increase venous thromboembolism risk three- to fourfold (up to 4 per 10,000 woman-years). 1

• Avoid COCs in women with active cardiovascular disease, history of thromboembolism, migraine with aura, uncontrolled hypertension, or known thrombophilia. 3

• Smoking is NOT a contraindication to COC use in women younger than 35 years, though it warrants counseling about increased cardiovascular risk. 1

When Oral Contraceptives Are Insufficient

• If COCs fail to control bleeding adequately, the next step is insertion of a levonorgestrel-releasing intrauterine device (LNG-IUD), which reduces menstrual blood loss by 71–95% and is more effective than any oral option. 3

• For women with contraindications to both COCs and the LNG-IUD, consider oral norethisterone acetate 5 mg three times daily for 10–20 days to achieve rapid hemostasis, particularly in perimenopausal women. 5

Common Pitfalls to Avoid

• Do not prescribe progestin-only pills (mini-pills) for heavy menstrual bleeding—they primarily thicken cervical mucus rather than suppress ovulation and do not produce the endometrial thinning required for bleeding control. 1

• Do not use depot medroxyprogesterone acetate (DMPA) as a first-line oral option—it is injectable, not oral, and causes unpredictable bleeding patterns that may worsen before improving. 1

• Do not place a copper IUD in women with heavy menstrual bleeding—copper IUDs increase menstrual blood loss and will exacerbate the problem. 5, 3

• Do not extend high-dose progestin regimens (e.g., norethisterone 15 mg/day) beyond 20 days without switching to cyclic dosing, as prolonged continuous high-dose progestin increases breakthrough bleeding risk. 5