Acute Progesterone Suppression of Wake vs. Sleep Luteinizing Hormone Pulse Frequency in Pubertal Girls With and Without Hyperandrogenism

This study is investigating how the hormone progesterone affects LH pulses (signals from the brain that control the menstrual cycle) in teenage girls, specifically comparing effects during sleep versus waking hours — which may help explain why some girls with excess male hormones (hyperandrogenism) develop irregular periods. **You may be eligible if...** - You are a mid-to-late puberty adolescent girl (Tanner breast stage 3 or higher, no more than 2 years past first period) - You are in generally good health - You are willing to strictly avoid pregnancy using non-hormonal methods during the study - You may or may not have signs of high male hormones (hyperandrogenism/hirsutism) **You may NOT be eligible if...** - You are male - You are pregnant, currently breastfeeding, or have a positive pregnancy test - You have obesity from a known hormonal or genetic cause - You have signs of a serious hormone-producing tumor (very high testosterone, rapidly progressive symptoms) - You have diabetes, anemia, severe blood cell abnormalities, or serious heart/lung/kidney disease - You have a personal history of breast, ovarian, or endometrial cancer - You are underweight (BMI below the 5th percentile for your age) or weigh less than 25 kg - You have taken hormonal medications, metformin, steroids, or stimulants within the past 2–3 months - You have a history of allergy to micronized progesterone Talk to your doctor to see if this trial is right for you.