Date of conception

[DreamyTiger]

Is there any fool proof way to work out date of conception?

Not if you were having regular sex over your fertile period the month you fell pregnant.
Sometimes people know because there was only one possible occasion! Or they can guess because one occasion was unprotected and the rest of the time condoms or another contraceptive method was used.

As previous poster says, no, unless you literally had sex once over your fertile period.

Sperm can live inside you for up to 5 days and even if using ovulation tests you ovulate anywhere from right then to 36 ish hours later, there’s no way of pinpointing an exact date unless there was actually only 1 possible date.

I know when I conceived but only because I had sex once in my fertile window..working the days back from my due date I conceived the day after sex

I had sex once in my fertile period which I think lead to the pregnancy. But there was also another occasion prior to this, just 2 days after my period stopped. I don’t think I was in my fertile window at this point but could have been if I ovulated earlier than expected

Not foolproof but the easiest way to get approximate date is to count back 38 weeks from the due date given at your dating scan.

It can be a few days out either way

How much does it matter? If it’s just curiosity, then I wouldn’t worry. If it’s a case of two possible fathers then you would need a DNA test to be sure.

I tracked mine, and both times the 12 week dating scan has only been ahead by two days from when I ovulated. So for me using that scan has been consistent with my ovulation. Using @sel2223’s approach above.

Thanks so much for your responses :)

I am going to start a new thread with more details