I am a 37 year old with unexplained fertility. I was on stimulating medication for IVF in November: Mirco Dose Lupron 10 units BID 75 iu menopur BID 175 gonal f BID They stopped the stimulating medication on the 6th day of stim due to low estrogen levels. They said the estrogen level did not double from day 4 to day 6, so it was best to cancel. (I had 10 follicles that measured 10mm on day 6 ultrasound) I have now started stimulating this month (on day 5 today) I am currently on: Mirco Dose Lupron 10 units BID 75iu menopur BID 375iu gonal f BID 5 mg letrozole (femara) once a day for five days I had my day 4 ultrasound and had 10 follicles measuring at 7 1/2mm with an estrogen level of 18. I asked if the letrozole could cause the the low estrogen level as well, and they seem to believe it does not. I am reading that it can cause a lower estrogen level. Would an estrogen patch help? Can you offer any insight and how I should proceed and if the letrozole is also contributing to the low estrogen level as we can't afford to have the cycle canceled again, as we are paying out of pocket and this is our only chance. Thank you so much for your time and help in this matter. MandeeView Thread