plasma progesterone , 17-hydroxyprogesterone , 20alpha hydroxypregn-4-en-3-one levels were determined twice weekly up to 16 weeks gestation , where possible , in a twin pregnancy , in two patients who aborted spontaneously and in three patients who were treated with 'progesterone supplements ' because of abnormal vaginal cytology .
C0020387
17-hydroxyprogesterone
C0033308
progesterone