HCG Trigger Shot Must Be Timed With Ultrasound Surveillance NOT With Calendar Dating When Doing IUI

Question:

I am writing from Hawaii with several questions. We will be undergoing our first IUI soon. The background is the following: I am 36 years old with no fertility factors. We decided to seek out fertility help because my husband, also 36, has an ejaculatory issue. I have been using Follistim AQ for the past 10 days and have two more days to go. My doctor instructed me to use my hCg shot at 11pm the night before my IUI. My first question is this, with only a 13 hour window between my hCg shot and IUI is this optimal? I have read that 36 hours is best.

Also, my normal cycle length is 26-27 days, I will be inseminated on day 16, will I still follow my normal cycle and expect to see my period on day 26? Should I ask my specialist for Progesterone supplements? I had 5 decent sized follicles 5 days ago, all between 10 and 12mm. Today during my ultrasound only 2 follicles were visible, one at 14mm and one at 15mm. I have been using a ClearBlue Easy fertility monitor, which said 3 days ago I was reaching peak fertility. Is it possible I already ovulated one or more egg? Thank you so much for your time. My doctor is a good doctor, but very busy and I often don't formulate my questions until after I have left the office. Mahalo! H. from Hawaii

Answer:

Hello H. from Hawaii,

First, let me say that I am a little skeptical of your doctor, based on your questions.

The optimal size for a follicle at ovulation is 18-20 mms. Using Follistim, your cycle should not be timed based on a calendar, but on the growth and size of your folllicles. In addition, at your age, the maximum number of ovulatory follicles should be no more than 3 because of the significant increased risk of a super-multiple if there is more than 3. So, the proper way to do this is daily ultrasound, if necessary, as your follicles reach closer to the 18 mm point. Once the follicle is 18 mm (my personal preference is 20mms), then the HCG shot is given and the IUI is done at 36 hours if only one IUI is done or at 24 and 48 hrs if two are done (My preference is the two IUI protocol).

The times don't have to be exact. The sperm just needs to be there reasonably close to ovulation and precede ovulation. Since it cannot be known exactly when ovulation occurs and it is know that it can take up to 12 hours for the egg to find and enter the tube, exact timing cannot be done. In general, follicles grow at 2mms per day but this can vary as well. That is why close ultrasound surveillance needs to be done as you get closer. If your doctor solely uses a calendar date, such as cycle day #16, there is a possibility of missing ovulation, which essentially dooms this cycle. In any case, based on a 27 day cycle (and counting backwards), you would ovulate at around cycle day #13 not #16.

I ALWAYS supplement with progesterone. It is an easy thing to do and there is no downside risks. If you have inadequate stimulation of progesterone in the luteal phase, you risk non-implantation and/or early miscarriage. I hate to take that chance when I can cover the risk by adding a little progesterone. I have written extensively regarding timing and doing IUI's in my blog. I would recommend you review that material and discuss your concerns with your physician.

Good Luck,

Edward J. Ramirez, M.D., FACOG

Executive Medical Director

The Fertility and Gynecology Center

Monterey Bay IVF Program

www.montereybayivf.com

Monterey, California, U.S.A.