Ovulation question

jassyflave

What’s the margin of error on early US? I have an irregular period so I have no idea when I OV and they’ve never used my LMP to date her because my first ultrasound was so far off from it.  It was June 4th but my ED of conception is July 9th with a DD of 4/1/19. I had sex on June 21st and then frequently after that. I really thought I got pregnant from the June 21st sex based on a few things but is that possible? And when did I likely OV? My early US were
August 3rd-5w5d
August 22nd - 8w2d
September 14th -11w4d
20 week anatomy scan
November 16th- 20w4d
I know 20w isn’t an early US but she was measuring spot on at the anatomy scan. Just wondering if it’s possible that I got pregnant from the June 21st sex and if not, when’s the earliest date I could’ve gotten pregnant?

mermaidca

Ooh that's way too much math for me at this point.  After my first ultrasound the docs all just went by that measurement and didn't bother with LMP dates or anything.  The other thing is that you don't necessarily "get pregnant" the day you have sex.  Sperm can live in your body up to 5 days so there could be a 5 day discrepancy anyways.  Only 11% of babies are born on their EDD anyways, that's why it's "estimated".

MRDCle

jassyflave

😂😂 yea it’s definitely a lot! I guess my question is if my estimated date of conception is July 9th, could the sex I had on June 21st be the sex that got me pregnant? I know everything is an estimation, I’m just wondering what the discrepancies can be between sperm life and early ultrasounds being off. 

jassyflave

And also when was it likely that inoculated based off the conception date. Sorry for throwing it all in there. I had a hard time reading it so I gave up and pressed send 😂

thatbaintforbetty

I would say probably not from the 21st. Early ultrasounds are fairly accurate. I would say you probably got pregnant from sex during the first week of July, and likely ovulated the later half of that week, or early the next one, give or take a day or two.   There is a margin of error but usually it’s a couple days, not weeks. 

My early ultrasound showed a 5 day difference from LMP but I also know she’s on the smaller side so I’m not sure how “off” it really is. 

MRDCle

Sperm can live for what, 5 days? So the latest that ovulation could occur would have been with 6/26. If by conception you mean implantation, implantation occurs about 7-10 days after ovulation which would be 7/3-7/6. 

If you’re concerned about your dating I would suggest speaking with your OB as they would have info about the validity of early dating scans. 

MRDCle

jassyflave said:
I had a hard time reading it

Welcome to the club. 

jassyflave

Thank you for your patience! I’m not that concerned I was just a little bit confused and wanted to make sure and see how far off it could be. You guys are great💕

squirttheturtle

I had a MC 6/26 and wasn't tracking cycles (because we weren't supposed to be trying).  I tested positive on 8/8, first dating US 8/21 and was 5w6d, confirmed dates 9/4 and was 7w6d.  I have measured consistent with my Edd of 4/19 all along...which would make Ov date around 7/27, 4ish weeks from MC.