How is the dosage of fertility medication decided?


I was wondering how the dosage of fertility medication is decided for each individual. Is there some kind of mathematical formula used by doctors to decide? My doctor recently upped my dosage of Menopur from 350IU to 400IU a day. I was just informed by the nurse yesterday and haven’t had a chance to ask the doctor why.

I couldn’t find much information on this topic so would really appreciate any answers.


I’m not familiar with Menopur so not sure if this is still correct but I know they changed my dose of Follistim based on what they saw in during the ultrasound and from the bloodwork. They started me at what I believe is their normal starting dose (I think 150) and when they saw how fast the follicles were growing and what my E2 was they changed dosing based on if they wanted them to grow faster or if they were growing too fast.


Thank you for your reply! I can understand that your dosage was changed during the cycle based on follicle development.
I wasn’t very clear but in my case the dosage was 350IU throughout my first cycle and we got 11 eggs and before the start of my new (current) cycle, the nurse called me to say that I will be using 400IU of Menopur this time. Since my doctor seemed to be satisfied with the quality and quantity of eggs retrieved last time, I just wondered why the dosage had been changed this time round and also how doctors decide the initial dosage for a first time IVF.


It could be that your bloodwork showed a difference in some your levels between when you did your last IVF and now? I am not sure but I would definitely ask.


I would definitely ask. Before my last IVF cycle my RE had me on the same exact protocol as the previous cycle. We had talked months before that about switching it up a bit so I mentioned that to him and he said “good catch”.

Sometimes we just need to be our own advocates and speak up. Call them and talk about it, let them know you’re curious about why it’s changing if everything was great last time. Good luck!