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Infertility/Fertility/Priming medications for FET shorten period?


Dear Doctor Ramirez,

I'm 43 and have just started FET cycle using donor eggs.  Starting day 4 of my period, I'm on Premarin 0.625mg (one tablet 3 times a day) and ASA 100mg once at evening.  On day 12 of my cycle, an ultrasound would be performed to see the thickness of my endometrial lining and I would then start progesterone tablets.  I understand from reading your blogs and Q&A that you would advice estrogen and progesterone suppositories instead of oral tablets.  But at the current clinic, the doctor only gave me oral forms of the meds.  

My period regularly runs for 7 days, trailing off the last couple of days.  But after I started Premarin and ASA, my period came to a stop on day 5.  Is this whats expected?   Does this mean the old lining hasn't been completely shed off?  Would the shortened period affect my endometrial lining for the upcoming FET and implantation?  

Thanks very much,
Mother Wannabe

Hello Sue from Hong Kong,

In FET cycles, the only requirement is to develop then ready the endometrial lining for implantation.  This is done with estrogen and then progesterone.  Clinics use different protocols for all aspects of IVF.  Studies have shown vaginal or injectable hormones to be the best in getting to the uterus (because it goes there first after being absorbed as opposed to going through the digestive system and liver first when taken orally), but as long as the uterine lining develops properly, oral certainly can work.  The key is to have an adequate endometrial lining.  The progesterone, which is started based on when the transfer is supposed to occur, changes the architecture of the lining to its final receptive state.  That timing is critical.

In terms of the early stoppage of your period, that is to be expected.  The rapidly rising estrogen level would create a new lining, thereby shielding the blood vessels exposed by the period, and stop the bleeding.  It is not anything you need to worry about.  It will not affect the timing of the lining.  FET cycles are completely programmed all the way to the date of transfer.

Good Luck,

Dr. Edward J. Ramirez, M.D., FACOG
Executive Medical Director
The Fertility and Gynecology Center
Monterey Bay IVF Program

Monterey, California, U.S.A.

for additional information check out my blog at check me out on twitter with me at @montereybayivf and facebook @montereybayivf.  Skype and internet comprehensive consultations now available via my website for those who want a more extensive evaluation that this site can accommodate


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Edward Joseph Ramirez, MD, FACOG


I am a specialist in infertility and advanced gynecological care. I can answer questions about infertility, gynecology related ills, menopause...virtually anything that affects women's health. PLEASE tell me where you are writing from as I am always interested.


I have been practicing as an Ob/Gyn and Infertility Specialist for over 23 years. Gynecology, advanced laparoscopic surgery, basic infertility, IUI's, IVF, reproductive surgery, and ovulation induction are all areas of my expertise. I am Board Certified. I have been doing In Vitro Fertilization in my clinic for 19 years.

American College of OB/GYN, American Board of Obstetrics and Gynecology, American Society of Reproductive Medicine, California Medical Association, American Association of Gynecologic Laparoscopists, Fellow of The American College of Obstetricians & Gynecologists

American Journal of Obstetrics and Gynecology, Wall Street Journal, Monterey Herald, SERMO, Women's Health and Fertility Blog

Medical Degree from Stanford University, Residency at Tripler Army Medical Center, Reproductive Training at Pacific Fertility Center, San Francisco

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