Postnatal resolution of large ovarian cysts detected in utero. Report of two cases.

Two cases of spontaneous resolution of large ovarian cysts in newborns are presented. In both cases the cysts were detected prenatally with ultrasound. In one case the cyst disappeared before birth; in the other, the cyst resolved several weeks postnatally. Both infants also displayed labial, uterine and vaginal enlargement, signs of maternal estrogen stimulation. These large ovarian cysts are also most likely under some hormonal stimulation and may undergo spontaneous resolution and therefore obviate the need for surgery.