Ovarian hyperstimulation syndrome in preterm infants.

Estradiol-producing ovarian cysts were found in four very preterm females at a postconceptional age that slightly preceded the expected time of delivery. The serum concentration of estradiol was very high. In the first infant one cystic ovary was removed surgically. When cysts appeared in the other ovary, the girl was treated with medroxyprogesterone acetate. The serum concentration of estradiol then fell and the cysts disappeared. Medroxyprogesterone acetate treatment was given also to the second girl, who had a high and rising serum concentration of estradiol. In infants 3 and 4 the cysts disappeared and the serum estradiol normalized spontaneously. Measurements of serum concentrations of luteinizing hormone and follicle-stimulating hormone before and after an iv injection of luteinizing hormone releasing hormone showed that preterm girls with early estradiol-producing ovarian cysts have a postpubertal type of response to luteinizing hormone-releasing hormone. When the test is repeated some months later they have a prepubertal type of response, which is normal for their age.