Biodegradable polylactate as a steroid-releasing polymer: intrauterine administration of d-norgestrel

Polylactate film containing 30 per cent or 4.5 mg. of d-norgestrel was fixed around a plain T-IUD and the device was inserted into the uterine cavity. Norgestrel was gradually released into the systemic circulation, blood levels being highest during menstruation. Plasma estradiol and progesterone determinations revealed that cyclic ovarian function was maintained during the intrauterine administration of norgestrel; however, marked local effects on the endometrium resulted. The amount of menstrual bleeding was reduced.