A woman with salt-wasting congenital adrenal hyperplasia presenting with a mucinous ovarian cystadenoma during pregnancy.

Women with congenital adrenal hyperplasia (CAH) caused by steroid 21-hydroxylase deficiency show reduced fertility, especially with the salt-wasting form. A 27-year-old pregnant woman with this disease underwent laparotomy and oophorectomy to remove a multilocular ovarian tumor at 14 weeks of pregnancy. This proved to be a mucinous cystadenoma. Toward the third trimester, she presented with marked elevations of 17α-hydroxyprogesterone and plasma renin activity. Careful management of endocrine and body fluid homeostasis allowed her to give birth to a healthy female infant with normal external genitalia. This case illustrates endocrinological parameters during pregnancy in a woman with classical salt-wasting CAH.