Question
Briefly describe combined Oral Contraceptive Pills. Add a note on emergency contraception. (3+1)
Answer
Combined oral contraceptive pills Contain an estrogen and a progestin. Mechanism: estrogen suppresses FSH (preventing follicular development), progesterone suppresses the LH surge (preventing ovulation), and progesterone additionally thickens cervical mucus and produces an endometrium unfavorable to implantation — three redundant mechanisms giving high contraceptive efficacy. Uses: contraception, menstrual cycle regulation, dysmenorrhea, acne. Adverse effects: thromboembolism (estrogen-driven, increased risk in smokers over 35), breakthrough bleeding, headache, weight gain.
Note on emergency contraception Taken after unprotected intercourse to prevent pregnancy, not to terminate an established one. Options: Levonorgestrel (single dose, most effective within 72 hours, delays/inhibits ovulation), Ulipristal acetate (a selective progesterone receptor modulator, effective up to 120 hours, generally more effective than levonorgestrel especially closer to ovulation), or a copper intrauterine device (most effective option overall, also provides ongoing contraception). Not intended for regular/repeated use as a primary contraceptive method.