LH peak occurs how many hours before ovulation -: (A) 36-48hrs., (B) 12-24hrs, (C) 48-72hrs, (D) 72-96hrs
Answer is B. Events Hours Oestraiol rise 83 Onset of LH surge 34-36 Oestraiol peak 24-36 LH peak 12-24 Progesterone rise 8 Approximate time interval of events in menstrual cycle prior to ovulation