The effect of a continuous low dose progestin on tubal and uterine motility.

The pattern of tubal and uterine motility was investigated in 16 women treated with 350 mcs megestrol acetate daily for 4 weeks. Myometrial activity characteristic of estrogen domination was recorded during the proliferative phase in most patients during the treatment cycle. A pattern of luteal domination was also recorded in most patients during the third week of the cycle but in some cases the pattern of uterine motility was considered atypical for the phase of the cycle and suggestive of insufficient progesterone secretion. In 1/2 the patients tubal motility was depressed during the treatment but a moderate degree of motility was retained by the tube at all times. The cyclic changes that occur in tubal motility during the normal ovulatory cycles were less pronounced or lacking in the treated patients. It is proposed that the estrogen dependent isthmic closure which occurs during the ovulatory period is impaired in the patients treated with megestrol acetate.(Authors modified)