<prompt> Progesterone pills act by which of the following mechanism?Thickening of cervical mucusInhibiting ovulationCausing aseptic inflammation in endometriumDestruction of embryo  <response>: Ans. a Thickening of cervical mucus. Ref. Dutta, Obstetrics.4th586, William Obstetrics 21st1531MINIPILLS Progesterone Only Pills E.g., levenorgestrol 30 meg, norethistrone 350 meg.- They act by thickening the cervical mucus.- It is very useful as a emergency contraception. Advantages- Side-effects attributed to estrogen are totally eliminated.- Lactational pill- No on and off regimen.- May be used by patients witha Hypertension, Fibroid, DM,b Epilepsy, Smoking, Thromboembolism.- Ideal for patients with sickle cell disease as progesterone is thought to treat bony crises. Side-effects- Amenorrhea, at times breakthrough bleeding- All side effects are attributed to progesterone may be evident- Simple cyst of ovary Failure rate 0.5-2 HWY. 