A 26 yo G2P2 comes to clinic on Monday. She and her husband just traveled and she forgot to bring her diaphragm. They had unprotected intercourse twice in the last 48 hours. Her BMI is 37. She has no major medical problems. You tell her that the best option for preventing pregnancy is immediate use of:
Combination oral contraceptive pills
Copper IUD can be placed up to 120 hours after unprotected intercourse and has a pregnancy rate of less than 0.1%. It inhibits fertilization by affecting sperm and tubal motility
Combined oral contraceptive pills can be used- generally take two separate doses 12 hours apart, but the pregnancy rate is 2-3.5%. There are side effects of nausea and vomiting.
Levonorgestrel-only pills can be used up to 72 hours after intercourse with pregnancy rates of 0.6 to 3.1%
If not interested in an IUD, the next best option is ulipristal acetate. This is a selective progesterone receptor modulator with antagonist and partial agonist effects. Can be used up to 120 hours after unprotected intercourse. Pregnancy rate of 0.9-2.2%
Ulipristal acetate may work better than oral levonorgestrel in overweight and obese women, but no studies have been adequately powered to determine definitive thresholds for body weight and emergency contraception
EC should not be withheld from women who are overweight or obese