Department of Obstetrics and Gynecology, Kyoto Prefectural University of Medicine
Corpus luteum, Ultrasonography, Luteal function, Ovulation induction
The corpus luteum was observed abdominally every 2 or 3 days after ovulation using electronic real-time sector scanner in 25 mormal menstrual cycles. We also studied the effects of hCG on the corpus luteum in 25 other cycles and the effects of various kinds of ovulation induction therapies in 91 sterile cycles. The relationship between the ultrasonographic view of the corpus luteum and luteal function was revealed. Corpus lutea were classified into two types in the mid-luteal phase. One type was solid with a thick wall and / or echogenic contents and the other was cystic with a smooth surface, thin wall and hypoechoic contents. The corpus luteum reached its maximal size on the 2nd or 3rd day after ovulation and gradually decreased in size until the next menstruation. The solid corpus lutea showed a significantly higher serum progesterone level than did those of the cystic type. (pIn cases of hCG administration, the solid types increased in number, but serum progesterone levels showed no significant difference between the two types. In the ovulation induction groups, especially those treated with hMG-hCG, the corpus lutea showed large sizes and long life times and tended to have another peak in size from 6 to 10 days after ovulation.