Measuring behind at 5 weeks 1 day

champhe

I looked to see if there are other posts related to this but didn't see any. I went in for an u/s yesterday and measured 4 weeks 3 days. According to the due date calculator I used I should be 5 weeks 1 day. This calculator took into account my average cycle days which is 30. Anyone had positive outcomes similar to this? My doctor said it could be normal due to longer cycle times but we would have to wait and see. They did see the embryo sac and a small yolk. Trying to not stress about this and hoping for the best. Thanks in advance! 

pshaortao

While the calculation factored in your cycle length, it did not know the exact day you ovulated, which could be off by a few days. I wouldn't stress and wait until a follow up ultrasound and see if the baby is staying on track with growth. The fact there is a sac and yolk sounds very promising!

slam1110

I agree with @pshaortao !  You could have just ovulated later than "normal". 

vrj0522

I agree with pp. Unless you were temping daily, you cannot know what day you ovulated. The luteal phase can be different from woman to woman (usually between 10-15 days in length) so you could have ovulated later than your calculator would tell you because the calculator only gives you a standard number and not one that is tailored to your own body and how your body works. 

julieannburkhart

This has happened with both my pregnancies because my cycle is usually 36 days and the OB calculates it at 28. I always measure a week behind but my son is healthy as can be and OB said this new baby looks great and healthy too.

champhe

Thanks everyone! 

kat81

Also, I found that these early dating ultrasounds can be off even if you DO know when you ovulated. I knew precisely with DS (temping, opk) and had a due date of 12/22. The ultrasound that I got just shy of 6 weeks stated my due date was 12/26. He came 12/18 (not that his arrival date is relevant, though.)

Because of unexplained bleeding & cramping I had, I got an ultrasound yesterday. I was supposed to be 6w6d given my LMP (but this time I did not know about my ovulation precisely), and they calculated it as 6w0d or maybe 5w6d. I was concerned and thought this was evidence I DID miscarry, but the tech was like, "there's the heartbeat." So seems like everything is fine. And I'm going to keep using my original EDD because I'm not going through an extra week of first tri, haha.