The purpose of this study is to determine if in late pubertal girls without hyperandrogenemia (HA), progesterone (P) will acutely reduce waking lutenizing hormone (LH) frequency to a greater extent than sleep-associated LH frequency. We hypothesize that in late pubertal girls with HA: (a) waking and sleep-associated LH frequency will be elevated (compared to controls); and (b) P will suppress waking LH frequency to a lesser degree than it does in girls without HA.