Is the baby mine?

[New93]

Recently I found out I’m going to be a dad the only problem is the dates don’t match up... on 3rd November she had her first scan and was told she was 6 weeks. Problem is the last time we had sex was 12th September which would leave a 2 week gap... and to make things worse anytime I bring it up she gets mad and try’s to avoid answering any questions to do with it simply saying it is 100% mine and I don’t have to worry. She doesn’t want me at the scan either which makes it even more strange... my question is am I right on thinking these dates don’t add up as I’m now concerned she has been unfaithful and the child’s not mine because of the 2 week gap. yes once the baby is born the first thing I will do is get a dna test but till then is she correct that I’m worrying over nothing or am I right to worry because of the dates ?

Hi OP,
So I’ve a slightly different experience - in that I now know from multiple pregnancies that my dates never quite “add up”. I have slow implantation and often get told at early scans that I’m a week or two behind (which for me has led to one successful pregnancy, and several losses). However, posters here are right. If you last saw her on the 12th of September, it’s really unlikely anything can cause a four week delay (other than a not developing pregnancy).

I’m sorry she’s getting mad and avoiding your questions. We often see threads like this where the dates are a few days wrong (which can easily happen) but 4 weeks is a long time! I hope you are as ok as can be

Why has she had a scan at 6 weeks? Has she had some problems?

"I don’t think it’s impossible that the baby is yours ??"

The discrepancy is 3.5weeks difference in conception date though?!

@Namechangeme87 I don’t know anything about her periods as we live long distance and with the way she has been acting I know she would never tell me and she only said 6 weeks she never mentioned anything about days, I will still get a dna test when baby is born it just means it’s a long time to be left in the dark wondering if I am or not

She should have been nine weeks pregnant at the scan.

www.whattoexpect.com/due-date-calculator/

Is it 3.5 weeks ? Sorry I’m tired 😓

I worked 6 weeks back from the scan as 22nd sep and they had sex 10 days prior to that . Which like I say if she was 6 weeks 5 days for example at the scan n accounting for sperm been able to live a while then not impossible ?

Of course the 6 weeks would be from her period not from
Ovulation But like I say maybe she didn’t have a Proper period / was implantation bleeding Or something n thought she did .

like I say I’m tired tho so maybe am just Been stupid with the maths ?!?!

Either way op if she is being weird about it with you and the dates don’t seem right then of course you are within your rights to question her !

As she's had a scan an implantation bleed wouldn't make a difference to the dates. Plus of the situation was genuine she'd also be confused and would be acknowledging that. I can't imagine dismissing my partner questioning me in this situation. In fact I've been throwing up in the morning and DH knows that if I would have had to have cheated to be pregnant - I brought the point up with him (I am most definitely not pregnant) as I couldn't blame him for thinking that!

The baby either isn’t yours

OR

she’s not really pregnant

@calimommy

Ok, every pregnancy is dated to the first day of the last period. Because it is very difficult to pinpoint exactly when ovulation occurs a pregnancy is dated by what is known -the period. So technically you get two 'free weeks' which are weeks when it is not possible for any woman to be pregnant but that's just how it's done. So by 40 weeks a woman has only really been pregnant for 38 weeks.

While this is correct, it doesn't help the OP at all because it means conception occurred AFTER the two "free weeks" - not before. This would only be relevant if the scan dated her 2 weeks further along than OP thought she could be. Whilst helpful in general, this is irrelevant in this situation

If you had last sex on 12th of September, then her last period before conceiving would be two week before this date- end of August- that’s given if her periods are regular per 28 days.
I had it similar like that- I felt pregnant on around

12th of August.
I found out I was pregnant 9.11th- I was already past 4 weeks as missed my regular period
My daughter was born in mid of May the following year.

Sorry I meant I found out on 11of September.

www.whattoexpect.com/due-date-calculator/result/june-05/
Sorry, but if you had sex on 12th Sept, she would be 10 weeks 4 days today, and the baby would be due June 5th. As someone else asked, why did she have a scan last week? Did she have it done privately? That scan picture should have a date on it, ask her for a copy of the scan photo.
Sounds like she’s having you on.

@theantsgomarchin I was only trying to clear up when conception would occur-ish for OP. He can draw his own conclusions from that time frame then. A lot of of people don't understand how pregnancy is dated. So yes, it is relevant.

@New93

The 2 week discrepancy is not an indication that the baby isn’t yours. How it works with pregnancy is from the day you conceive you’re already 2 weeks pregnant because the pregnancy starts from the date of your last pregnancy.

For example.

1st November - get your period
14th November- ovulate, have sex and conceive
30th November- congratulations you’re 4 weeks pregnant (you only had sex 2 weeks ago but you got your period 4 weeks ago so that’s when the pregnancy started).

Google will confirm this for you. Any midwife/medical professional will confirm this for you. If you ring your GP they will confirm this for you.

I understand why it’s confusing though. Fwiw I’m currently 9 weeks pregnant with mine and my husbands second baby. We had sex 7 weeks ago. We did not have sex 9 weeks ago...but I havnt had sex with another man since I met him years ago, pretty confident baby us his

I think posters should consider that some men use Mumsnet as an "Ah-ha gotcha" tool against their vulnerable partners.

I think automatically assuming a woman is vulnerable and a man is a threat is unfair.

The OP has probably come to mumsnet because the women here will know a lot more about cycles, conception and pregnancy than on a mens forum. It's not that difficult to understand

And on top of that he is correct to be confused and even suspicious given there is roughly a 3 week gap from when it was possible for him to be the father, and his DP is not inviting him to the scan or offering more information nor even is she mutually curious about the date thing.

OP I actually agree with a previous poster - is she even pregnant??

*from the date of your last period

@New93
Don’t feel bad about being confused about how this works. It is confusing and must be very hard in a situation where you’re not in a long term relationship, baby isn’t planned and you have doubts over whether you’re the father.
Maybe you’re not, maybe she had sex with another a few days either side of you, but I wouldn’t at this stage think these dates ‘prove anything’

I actually had to have all this explained to me by my hubby (he’s a doctor) after we conceived our first. We’d been trying to get pregnant but I just didn’t ‘get’ the way they did dates at first.

@GlendaSugarbeanIsJudgingYou yup

Which is why I was trying to be balanced as it’s quite a big deal to be telling someone a baby is 100 not there’s

As I said above am tired so my maths may be way out but I don’t think that’s it’s totally impossible the baby isn’t his

Don’t scans go purely by measurement ( you’d think I’d know this after 3 pregnancies but no I don’t ) and often date u less along than u thought because they don’t account for period ?

Early scans can also be out by a few days so google tells me

So Combo Of - early scan not been accurate,
She is saying scan shows 6 weeks but could be 6 weeks 4 days for eg,
And the fact that sperm can live a few days before fertilizing the egg if you wind that all back looking at the dates then that would take you to when they had sex ?
I think ??

Just playing devils advocate tbh there’s now way I’d say it’s 100 percent not possible

Of course she could be lying aswell

You aren’t in a relationship with her now - I’d not get caught up in the dates now - wait until she has the child and then have a DNA test - keep your distance from her as you said she was unfaithful - don’t feel any responsibility to her - it’s the child you would have responsibilities for once it’s born.
Once you know the child is your then you can step up.
In the mean time, carry on your own life and hold your head high.

Sounds like she’s having you on.

Good point.

I’m not sure why you are so anxious. You don’t see each other much and DNA testing is widely available. Just wait like she has to,

She has to raise an entire human being in her body, so be kind. The actual baby won’t affect anything for you until it’s born and until then she’s still your girlfriend going through a massive change to her body,

If she has cheated she won’t be any wiser than you about paternity will she ? It could still be yours or with enough possibility she couldn’t say for sure it’s not.
I found dating to be wildly off if you have short periods and long cycles. My due dates were nothing like the the average number from conception to birth and DS arrived spot on that date, not the last period one.

Surely it's understandable why the OP would be anxious, he might be a father!! I don't get MN sometimes.

You can be empathetic to the allegedly pregant woman without dismissing the OPs feelings.

Is she saying she's 6 weeks pregnant by her own calculations, or is that what the scan dated the foetus to? Because if she should be 9 weeks pregnant but the foetus looks like it's 6 weeks, there may be a problem with its development. I'd be interested to know if a heartbeat was seen.

It's hard to establish. In very early pregnancy the gestational age of my babies wandered from one scan to the next (lots of time in the EPAU thanks for asking), bc they do grow in spurts rather than steadily. As a PP pointed out, if she thought she was 9 weeks exactly but the foetus measures 6 weeks 6 days, it could still be normal variation. Just? But if this baby is his, it's measuring behind.

Also whether she 'wants' you at the scan is a red herring. Presumably women still have to go to them alone, as per covid regs?

@calimommy

Ok, every pregnancy is dated to the first day of the last period. Because it is very difficult to pinpoint exactly when ovulation occurs a pregnancy is dated by what is known -the period. So technically you get two 'free weeks' which are weeks when it is not possible for any woman to be pregnant but that's just how it's done. So by 40 weeks a woman has only really been pregnant for 38 weeks.

Except the missing two weeks are in the wrong direction

They're before the missed period not after it