Ovulation prediction and detection in spontaneous and stimulated cycles

ABSTRACT

The accuracy of various methods in predicting and detecting ovulation is evaluated in 24 ladies 10 with spontaneous and 14 with clomiphene citrate [CC] induced cycles. Starting at day 8 of the cycle, all subjects were followed with daily transvaginal ultrasound [TV-US], rapid radioimmunossay [RIA] measurement of both serum luteinizing hormone [LH] and estradiol [E2], determination of urinary LH with Fluoroimmunoassay [FIA] together with recording of basal body temperature [BBT]. Progesterone in serum was measured 7 days after ovulation detection. The mean follicular diameter [MFD] of the pre-ovulatory follicle was significantly larger in CC-stimulated cycles than in spontaneous cycles [29.2 +/- 1.1 mm versus versus 21.8 +/- 0.5 mm; P 0.001]. Post-ovulatory serum progesterone was higher in CC cycles [35.2 +/- 3.9 ng/ml] than in spontaneous cycles [18.5 +/- 2.1 ng/ml] significantly [P 0.005]. Mean daily serum LH levels were similar in both groups. Peak values of 40 mIU/ml or greater preceded the day of ovulation as detected by sonography in all cycles. Serum E2 peak was significantly greater in CC-cycles than in spontaneous ones [950 +/- 40 and 450 +/- 22 pg/ml respectively, P 0.01] in 96% of the cycles. BBT nadir predicted the day of ovulation in only 12% of cycles in all cases. LH surge in urine was pronounced after serum LH peak in blood 85% one day after [i.e. at the day of ovulation] and 15% 2 days after [almost similar in both groups]. TV-US is revealed to be an excellent method for detection and timing of ovulation and FIA of urinary LH is a very useful method for prediction of the day of ovulation