Pregnant women with impaired tolerance to an oral glucose load in the afternoon: evidence suggesting that they behave metabolically as patients with gestational diabetes.

OBJECTIVE: In previous studies we observed the existence of a circadian variation of the blood glucose response to oral glucose in pregnant women with higher values at 4 PM. Some women with increased risk of diabetes with normal oral glucose tolerance tests at 8 AM also had values above maximum normal levels at 4 PM. The aim of this trial was to determine the clinical significance of this impaired tolerance in the afternoon. STUDY DESIGN: Seventy-seven pregnant women with normal risk of diabetes (65 of normal weight and 12 overweight), 75 with increased risk of diabetes (26 overweight), and 12 patients with gestational diabetes were incorporated in the study. All women underwent two oral glucose tolerance tests (1.5 gm/kg) at 31 to 32 weeks' gestation at 8 AM and 4 PM with a 1-week interval. At 33 weeks' gestation a whole-day blood glucose profile was performed with usual food intake; samples were withdrawn before each meal and at 30, 60, and 120 minutes after each meal. The weight of the newborns was recorded. RESULTS: (1) Results of oral glucose tolerance tests confirmed a circadian variation of the response in all groups; (2) 37 women with increased risk of diabetes had higher values after oral glucose tolerance testing than the normal threshold at 4 PM but not at 8 AM; (3) among women with normal risk of diabetes all values were within the normal range despite the circadian variation; (4) blood glucose levels during whole-day profiles were normal in women with normal risk of diabetes and with increased risk of diabetes with normal oral glucose tolerance testing at 4 PM, whereas all women with increased risk of diabetes and impaired tolerance in the afternoon showed hyperglycemic episodes; (5) the percentage of newborns with high weight (>90th percentile) among women with increased risk of diabetes and abnormal oral glucose tolerance tests at 4 PM was similar to the percentage found in women with gestational diabetes and much higher than the one observed in women with normal oral glucose tolerance tests in the afternoon. CONCLUSIONS: The impairment of the response to oral glucose tolerance testing seen in some patients with increased risk of diabetes at 4 PM but not at 8 AM seems of clinical significance in view of the abnormal whole-day blood glucose profile these women had and the weights of the newborns.

Pituitary and ovarian response to acute stimulation with LH-RH in normal and anovulatory women.

The LH FSH estradiol and progesterone responses to acute stimulation with LH-RH were studied in 12 normal women with ovulatory cycles (4 in the initial follicular phase, 4 in the mid-follicular phase and 4 in the late follicular phase) and in two castrated women, two under hormonal contraception, two with ovarian amenorrhea, twelve with central amenorrhea of no detectable origin (6 with normal and 6 with low basal gonadotrophins), eleven anovulatory patients with pseudomenstruation, two with anorexia nervosa, and two with pituitary amenorrhea. Each woman received a rapid i.v. injection of 100 microgram synthetic LH-RH at 9:00 a.m. Serum levels of LH, FSH, estradiol and progesterone were determined by radioimmunoassay in samples collected before and 60, 120, 240 and 480 minutes after injection. The findings were : 1) A significant rise in estradiol and progesterone levels, in addition to LH and FSH elevation, in normal women; 2) A lack of ovarian steroid response in the castrated women and in ovarian amenorrheas, which suggests that the source of steroid response to stimulation is not extragonadal; 3) Significant differences in the responses of the four hormones to LH-RH in the women with central amenorrhea in comparison with the normal group with great variability of results; the steroid response in the presence of a positive LH response might correlate with the severity and/or prognosis of the disorder, a point deserving further study; 4) In anovulatory women with pseudomenstruation, LH responses for the most part normal, and particularly, progesterone responses.

PIP: Simultaneous pituitary and ovarian responses to acute stimulation (100 mcg iv injection) with luteinizing hormone-releasing hormone (LH-RH) in normal women at different times of the menstrual cycle were determined and the results were compared with those obtained in women with anuvulation from different causes. There were 12 normal women, 2 women who had had surgical oophorectomy, 2 who were taking combined hormonal contraceptives, 1 with amenorrhea following pelvic irradiation, 1 with gonadal dysgenesis, and 2 with anorexia nervosa. There were also 12 patients with secondary amenorrhea without detectable pathology. All patients received an iv injection of 100 mcg of synthetic LH-RH. In the normal patients basal LH levels were significantly (p .05) higher on Days 13-14 of the cycle than on Days 4-5. In all 3 phases of the cycle, LH reached peak poststimulation levels within 60 minutes after LH-RH injection. Castrate women showed basal LH levels and LH response profiles similar to normals. There were no estadiol or progesterone responses in this group. Women using hormonal contraception showed low basal levels of both gonadotropins with poststimulation LH response but no follicle stimulating hormone response. Estradiol response in this group was slightly lower and more sustained than in normal women. In patients with ovarian amenorrhea, responses were similar to those in castrated women. In patients with anorexia nervosa findings were normal.