[Prediction of ovulation]

Prediction of ovulation was carried out by B-ultrasonography, BBT graph, cervical mucus and appearance of mittelschmerz in 45 normally menstruation women for a total of 72 cycles. LH peak values were also determined in 20 cases (20 cycles). The results were as follows: 1. The relation-ship between each index and ovulation: (1) The ultrasound image of follicle: average daily follicular growth during the 4-5 day before ovulation was 2.5 +/- 2.1 mm (means +/- s). Average diameter of the biggest follicles one day before ovulation was 20.6 +/- 2.0 mm. (2) The change of cervical mucus: the opening of external os and the secretion of mucus with ferning became most typical one day before the ovulation. (3) BBT graph: in a majority of cycles, ovulation occurred at the first day of the initial rise in temperature. (4) Mittelschmerz: occurred in 35% of cycles and appeared within 24 hours before ovulation. (5) LH peak value: ovulation occurred 24 to 48 hours after the first significant rise of LH, and within 24 hours after LH peak value. 2. The relation-ship between indices: in the majority of cases, when we employ the ultrasound image of follicular rupture as a signs of ovulation, LH peak value, follicle of biggest diameter, maximum volume of cervical mucus, the lowest point of BBT and mittelschmerz appear on the same day, namely, one day before ovulation. The authors suggest that ultrasonography used combination with other parameters provides a feasible and relatively accurate and reliable method for the prediction of ovulation in clinical practice.