865566 tn?1356700362

Timing of HCG trigger shot with IUI

Hi there.  I am scheduled to have an IUI on Saturday.  My concern is the timing of the trigger shot.  My understanding is that if I have a LH surge BEFORE the trigger, then there is no point in doing the trigger shot.  Is this true?

Normally I ovulate on day 12 or 13, and my follicles have never been above 20mm, on monitored cycles.  My endometrium measured 6.2 on day 10 this cycle - it has never been greater than 7.2, even as late as CD13.   I did not have my normal RE this month, and I am concerned that he doctor's decision was not the correct one for my case.  

This month I took 5mg Letrozole CD3-7.  Ultrasound on day 10 (Tuesday) showing one follicle at 16mm and one at 17mm.  Based on the follicle size, they scheduled me for IUI on Saturday morning (CD 13), with a trigger shot at 8pm Thursday (CD11).  

Because of my concern, I have been doing LH tests, hoping that my surge would be delayed until after the trigger shot.  So of course, I got a positive LH test this afternoon around 3:00.  I'm not to do my trigger until 8:00.  I called the clinic and the receptionist told me that if the nurses did not advise me to be checking for a surge, then i should just disregard it all together.  

Could you please explain how the trigger shot works, what it does, and if it is effective if taken after the LH surge?

Thank you so much!  

3 Responses
Sort by: Helpful Oldest Newest
603463 tn?1220626855
The trigger shot ( HCG ) simulates the LH surge.  And the ladies of the forum are correct that ovulation should occur 36 hours after the shot.  IUI should be done at that time, or slightly before if that is difficult to arrange.
I don't think that there will be a problem if you have your natural LH surge and the trigger shot on the same day.  You should definitely have your IUI within 36 hours after the trigger. By the way, follicles of 20 mm are fine.  I hope the 16mm follicle got a little larger before the trigger ( I"m sure that it did!).
I hope this is helpful, and I hope it all works out!
Dr B
Helpful - 0
Avatar universal
I think you will be ok. When you get the LH surge from the OPK that means you will ovulate in 24-36 hours.  
If you got the surge yesterday & do trigger,  when they do the IUI on sat am you should make it.  It all falls in the time line of the 24-36 hrs.

Best Wishes to you!!
Helpful - 0
982214 tn?1471454781
All the IUI's i had (except the first) were monitered by ultrasound because we did the opk and missed O the first time. That is when we monitered by US and did the trigger shot. The trigger shot is suppose to work in 36 hours so if you are having a morning IUI (like i did) i had to do the trigger shot at 11:30pm-12:00am 2 days before. So say my IUI was on April 15 at 11:00 am...I would have to take my trigger shot at 11:00pm on april 13.

I hope that helps!!! Good luck and SSBD!!! :0)

Helpful - 0

You are reading content posted in the Fertility / Infertility Forum

Popular Resources
Many couples are turning to acupuncture to treat infertility. But does it work? We take a closer look.
Does exercise really lower fertility? We take a look at 8 common myths about fertility.
Your guide to safely exercising throughout your 40 weeks.
Learn which foods aren't safe to eat when you're eating for two.
Is your biological clock sounding the alarm? Dr. Elaine Brown explains new advances in egg freezing.
Herpes sores blister, then burst, scab and heal.