Sex hormone levels and intestinal absorption of estradiol and D-norgestrel in women following bypass surgery for morbid obesity.

A report of reduced serum levels of progestins, following oral administration after jejunoileal bypass, promoted the present investigation of the absorption of D-norgestrel and estradiol following different types of intestinal bypass surgery for morbid obesity. A group of non-operated obese patients served as control. Apart from significantly higher gonadotrophin levels, which could be attributed to periovulatory sampling in the non-operated group, there was no significant differences in basal levels of estradiol, estrone, conjugated estrone, androstendione, testosterone, and progesterone. The operation did not influence the pattern of the menstrual cycle. Following a single oral dose of 4 mg micronized estradiol and 125 microgram D-norgestrel, serum levels of estradiol and estrone were equal in the three groups. serum D-norgestrel was equal in the two operated groups, but was significantly higher in the bypass group with 1:3 jejunoileal ratio, compared with the non-operated group. Further, a significant negative correlation between peak levels and weight was found. It is suggested that one year following bypass surgery, obesity - but not intestinal bypass - might be associated with reduced serum levels of exogenous sex steroids following oral administration.