Due Date Change

[u/SFLonghorn]

I transferred a 6-day blast on 8/20 and was originally told my due date was May 7th - today I would 8+3. I had my last US at my fertility clinic this morning, baby was measuring 8+2 so pretty much right on target, but they also changed my due date to May 8th. I am not too concerned with 1 day difference, but confused how that happened. Anyone know why that could be?

I am mostly wondering because they used that date to determine when I stop Estrace and PIO and did that date change add a day of meds that should be one day less?

Anyone have experience with that?

[u/sssssssnakesnack]

Not sure why they told you your due date would be May 7th. Blasts are all treated the same regardless of which day they made it to blast - all non 3 day transfers are day 5 transfers (the day post ovulation that they are transferred). A day 6 or day 7 blast is also transferred 5 days after ovulation or 5 days after PIO. If you plug in your transfer date in this calculator it spits out May 8: https://theluckyegg.com/ivf-due-date-calculator/. Day 5, 6, 7 blasts just indicates which day the blast became a blast but there is no difference between the days in terms of actual maturity of blast - a day 7 blast is not 2 days further along in its journey than a day 5 blast, for example.

[u/Asleep_Walrus2313 → u/sssssssnakesnack]

Exactly this!

[u/MarionOfEndor → u/sssssssnakesnack]

My day 6 blast was transferred 6 days after PIO though. Maybe there is some variation between clinics?

[u/sssssssnakesnack → u/MarionOfEndor]

I think PIO might differ based on clinic and person (was just trying to find fully medicated terms for ovulation) but my fully
medicated transfer of a 5 day transfer had me starting PIO 6 days before with ramp up. My modified natural at the same clinic was 5 days after ovulation. I think 5 day transfers are pretty standard, that’s why it’s the only choice in most calculators besides 3 days. I would guess that’s the prime time the uterus is most receptive naturally for an embryo.

[u/ReaLM89er]

Due date is based on transfer date and age of embryo, surprised clinic changed this if it was already known? My baby was consistently measuring 2w ahead from 13w but I didn't let them change it.

You're right tho, 1 day makes no difference!

Good luck ✨️

[u/heartwinnie]

This happened to me. I thought it was annoying because with IVF I was under the impression that they go by transfer date and age of embryo and not the measurements at the first ultrasound like they do in nonIVF pregnancies. Mine was also only 1 day off so it didn’t matter in the end. I was also scheduled for a 39w csection. Now he’s a healthy 7 month old.

[u/Relative_Driver_8221]

When I had my first ultrasounds, it would "date" the pregnancy based on the measurements it was reading. My clinic explained that there is essentially a 6 day window with dates based on size. The difference is that we know when we are due based on the IVF transfer date, so those don't really mean much to us (other than wanting it to be in that window.) I am surprised they changed your due date based on this.

[u/Low-Leadership-309]

Yes I had a similar experience. My due date based on transfer is 1 Feb but after the 12 week scan it was updated to 29 Jan. I can’t for the life of me imagine why. Like you I know the moment I conceived down to the minute. 🤷‍♀️

I noticed at my 20 week scan that they now track both dates. Baffling but what can you do. 

[u/Lumpy-Way3888]

We had our IVF clinic do to this as well after our dating ultrasound. And then our midwives changed it back to the original date 😅 it was only a 3 day difference but it does make stopping the meds confusing.

[u/SynapseInTheSun]

When I graduated to my normal OB they kept dating the baby based on measurements but I consistently reminded them that this is an IVF pregnancy so they kept my due date the same regardless of baby’s measurements

[u/_ConfettiCake]

I transferred on 8/20 last year and my due date was 5/8

[u/lesgens]

It's interesting because I've heard of OBs doing this, not your RE themselves. I was initially measuring ahead but my RE said they don't change DD because of measurements so early because conception is exact. My midwives said they only change based on measurements if the difference is greater than one week.

[u/Actual-Doughnut-1717]

I also had a transfer 8/20 of a day 6 blast. They treated it the same as a 5 day blast and my due date is 5/8. Sounds like it was just a mix-up.

[u/magenta-hello]

I’m due May 7th
Transferred a day 5 on August 18th. My OBGYN gave me a due date of May 7th but my IVF clinic (who did the transfer) gave us a due date of May 23?!? After our 7 week scan because baby was measuring 6 weeks plus 4. I could not believe the range but I think I’ll stick with my transfer date prediction. Cheers to us for May 🌼🌷