A woman wants a prescription for an oral contraceptive, and your choice is between an estrogen-progestin combination and a “minipill” (progestin only). The main difference is that, compared with the hormone combination products, progestin-only drugs (LQ)
|A||Are associated with a higher risk of thromboembolism|
|B||Are directly spermicidal|
|C||Cause more menstrual irregularities (irregular cycle length, amenorrhea, spotting, etc.)|
|D||Have better contraceptive efficacy|
a. Progestin-only oral contraceptives (“minipills”) are associated with a higher risk of menstrual irregularities than the more common estrogen-progestin preparations. That is largely due to the lack of estrogen.
b. However, the absence of estrogen also lowers the risk of thromboembolic disorders.
c. Progestin-only formulations are, overall, less effective in terms of preventing pregnancy than combination products; like combination products they lack definitive spermicidal effects (but they thicken cervical mucus, retard sperm motility in that way, and reduce the likelihood of nidation), and their administration schedule is continuous—every day, rather than the cyclic schedule used for combination products.