Please help not sure about dates

[Scared0517]

I first slept with my boyfriend on 29 September after having my period 25-29 September. I realised I was late and had bloot tests and an Ultrasound on 26 oct which showed a sac and nothing else. It scan told me I was 7 weeks 3 days. I had a second scan yesterday 9 October and there is a heartbeat & the scan told me I was 7 weeks 1 day. This is virtually impossible with my boyfriend because of the first date we slept together. The time before that date I last had sex was on 6 September.. But I did wear protection & get my period 25-29 Sept.

Is it possible the ultrasound dates are wrong and my boyfriend is the father? Or is there the possibility I conceived on 6 September?

Hope you can help xxxx

Hi Scared

From your dates you are likely to have conceived around 9th October. They count the two weeks before you even ovulate so you are classed as pregnant before you even had sex!

At 7 weeks it is difficult to date the pregnancy because the embryo is sooo tiny so they may have overestimated slightly - the date given usually allows for + or - 5 days which would make sense in your case as your cycle began on 25th September which would make you six weeks and 3 days.

So no need to panic. Good luck with your pregnancy :)

Yep I agree with above post these dates there given u go with your last period date of the 25th September so looks like ur bf is the father as they class u as pregnant from your last period but you actually don't ovulate until 2 weeks after ur last period. It gets very confusing. U can google conception dates calculator in google and it works out wen u conceived and I think ull find it will say in October so congratulations xx

The only thing I don't understand is that you would have been unlikely to have been ovulating the day that you finished your period, in fact near impossible.
I know that the sperm can stay alive for up to five days before ovulation occurs (normally 2 weeks from the start of your period)

If you say your period started 25th September you would have been ovulating (when one of your eggs is released from your fallopian tube) around Monday 8th October, this means that sperm would have had to survive around 10 days which is not possible.
Is it possible that you had sex again on a later date just before or on the day you ovulated (around the 8th?)

I had my period from 21st-24th September, and ovulated on Wednesday 3rd october (13 days later) I had sex on 30th and 2nd either of these days could have done it. It gives me a due date of 28th June and made me 7 weeks on Friday just gone. This suggests that your scan is correct give or take a couple of days as we had our periods within 4 days of each other.