Irregular Periods and Pregnancy Possibility: Interpreting Cycle Changes

Menstrual irregularity (late, heavy, then light) does not exclude pregnancy and may suggest it.

Possible Pregnancy-Related Patterns

• Late period: Most common early sign.
• Heavy bleed: Could be decidua shedding (hormonal withdrawal) or miscarriage — not implantation (which is light).
• Light subsequent bleed: Breakthrough bleeding from hormonal fluctuation; may mimic period.

Non-Pregnancy Causes

• Anovulatory cycle (PCOS, stress, thyroid, perimenopause).
• Endometrial polyp/fibroid.
• Coagulopathy, anticoagulants.
• IUD/implant irregular bleeding.

Action Plan

1. Urine hCG test (day of expected period or later).
2. If negative, repeat in 1 week.
3. If positive or uncertain: Serum β-hCG + transvaginal ultrasound.
4. Track cycles (app/calendar) for pattern recognition.

Any bleeding in pregnancy warrants evaluation (ectopic, miscarriage, molar).