For those who have had in vitro, or others in the know...

[StaceyinLA]

If you have a blastocyst transfer, what is your EDD based on? I'm thinking conception date, but since the blastocyst is technically 5 days post-conception, how do they adjust for that?

 

I'm just curious. My niece has done a cycle and is pregnant, and I don't want to ask too many questions (although she has confided in me about a good bit of it), but I would just like to know.

 

Also, prayers for sticky baby (or two - they don't know for sure yet if it's two) would be appreciated!!

[Ravin]

Well, pregnancy is usually counted from first day of last period before conception. I would count ahead 36 weeks from the implantation date and mark from there and 4-6 weeks after as estimated due date.

 

Real life is not as precise as we would like it to be.

[StaceyinLA]

Well I know how it would usually be counted, and that's why it confuses me. I mean they are transferring a blastocyst that has already made some days' progress, so it seems that would take a little time from the overall gestation. At least that's what it seems like to me. I am just really curious as to how they arrive at a due date since they know EXACTLY when they implanted the already 5 days developed egg.

 

OR is it because everything is synced up perfectly, so you are technically exactly the same as if you would've conceived naturally? That thought is just now occurring to me.

[Guest]

You can naturally ovulate on day eight of your cycle. Or day five. Or day twenty. Estimated due dates are just that - estimation. You can get a quick implantation of a blastocyst or a slow one. You can be a mama who gestates quickly or slowly. I have a friend who naturally gives birth between 35-36 weeks with healthy, full term babies and another friend who was induced at 41 weeks and had a baby with barely mature lungs.

 

There is SO much variation in conception and gestation, and that doesn't go away just because someone had IVF. So whatever her due date (based on the age of the embryo, day of transfer, last period, whatever) just expect a window of four or five weeks where she could conceivably give birth to a healthy, full term baby and call it good :)

 

I've just started telling people the general season in which I'm due, because I'm one of those women who has had 42 week pregnancies and 37 week pregnancies and even after five, now six, of these it hasn't gotten any easier to predict. I know the exact days I ovulated and still can't call it with much accuracy, even though my dating ultrasounds early on are always right on the money.

 

Congratulations to your niece and I'm wishing her a happy, healthy pregnancy with zero complications or drama, whenever the baby decides to come!

[StaceyinLA]

Thanks for the response. I do totally understand that not all women are going to have the same experiences. I also understand that due dates are imprecise.

 

That being said, they do still give due dates to pregnant women, so I was just wondering if they calculated due dates differently when someone does in vitro? It's certainly not because I expect she will have the baby on that date, but I was just curious if there was a difference in how they'd calculate it, since the conception date would be so much more precise and the blastocyst would already have begun to develop.

 

I was thinking maybe someone who had been through the in vitro process might be able to offer insight.

[MistyMountain]

If I remember correctly from an old fertility board the people who had IVF counted the days past transfer rather then ovulation and could usually get a positive a few days earlier then if you were counting from ovulation. It typically takes 8-10 days but it can occur from days 6-12 days after ovulation to implant and that is when the hormone levels start to rise and you can detect it maybe a day or 2 later on a very sensitive test. Implanting late has a higher risk of miscarriage. With IVF it is transferred and it is like a little head start.

[ktgrok]

seems it would be counted from the day the egg was fertilized, and call that the "ovulation" date. But I'm guessing :)

 

[Janeway]

38 weeks from the day of the egg retrieval. If it is a FET, take the days old and subtract that from the 38 weeks.

[wapiti]

seems it would be counted from the day the egg was fertilized, and call that the "ovulation" date. But I'm guessing :)

 

This is correct.  38 weeks from retrieval would be the EDD.  (ETA, or 38w minus 5 days from the date of blast transfer.)

Edited May 21, 2016 by wapiti

[Guest]

EDD was from LMP

BFP on 10 DPO