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Can the exact conception date be told?

(5 Posts)
Ljones29 Mon 06-Nov-17 10:19:45

Im just wondering i had my period on the 2nd may and me and my husband had sex on the 14th and 16th (he didnt finish on the 14th). When i went for my first scan my due date at 6 weeks 6 days was the 9th Feb instead of the 6th from my lmp. Its now been changed and kept from the dating scan at the 4th Feb but that makes me further on than i know as i know my lmp was the 2nd may? Im just a bit confused

Justbookedasummmerholiday Mon 06-Nov-17 10:21:14

Nobody can say exactly when the embryo implanted so date is given from lmp instead! Only 4% of babies arrive on due date anyway!!

mindutopia Mon 06-Nov-17 12:30:58

No, it's impossible to say unless you are charting your ovulation and even then it's a guess within about a 24-36 hour period usually. Most likely it was on or after the 16th based on what you said, but it's very normal for dates on scan to not align perfectly with your lmp. Sometimes you ovulate earlier or later than you think and even when you know when you ovulated, implantation could be later or earlier and that might affect fetal growth. With my first, I was moved 4 days earlier and with this one it was 2 days. It's very normal to be as much as 6 days or so off, even when you think you know when you ovulated.

mindutopia Mon 06-Nov-17 12:32:08

That said, they should be dating you from your 12 week scan. Dating isn't as accurate at this point in pregnancy so they shouldn't still be moving your dates around.

Ekphrasis Mon 06-Nov-17 14:59:11

I don’t think it’s that accurate, and can be out by a week either way. There’s no way I’m 13+2; I’m sure the furthest I can be is 12+6 but that’s where baby is currently measuring. I had this with my son too. It’s just the way they measure and date and keep the monitoring process going .

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