Due date doesn't match conception

[Tina2016]

Hello
I am 28 weeks pregnant and my EDD is the 19th September. My last period was the 16th December 2015 and I know me and my partner had sex on the 30th December early hours twice without protection. We had spent xmas apart because we were with our families and now he's questioning conception and due date. Which is making me question things even though I know I've done nothing wrong. I have tried to explain I may have ovulated later than normal.
Tina

I put your last period into babycentre calculator and got 21st sept.

Your EDD is only a guide and you can be anything from 37-42 weeks when you actually give birth. That's five weeks!

To be honest I would tell him to go fuck himself. How rude of him. Are you sure this isn't a way of him trying to get out of being a father?

But those dates basically do match?! Remember due dates are +/- a week anyway...

Mine didnt match either. I know exactly when I concerti end but my EDD make it bout two weeks earlier (before my last period). I also have a short luteal phase ;ovulate 8 or 9 days in).
The E is for Estimate. They look at the size of the foetus and calculate how many weeks but every us different donuts just a guess. At every scan my EDD changed and then i went to 41wks.

Your dates sound fine to me, I got pregnant just after New Year/Early January and my due date is the 25/09

Bloody hell sorry for all typos. DD is asleep on me

www.nhs.uk/conditions/pregnancy-and-baby/pages/due-date-calculator.aspx

gives 21st based on a 28 day cycle so thats about right

It's just a rough estimate, he's being an offensive arse.

Does he realise that sperm can hang about for quite some time inside you? Up to about 5 days I think. So conception can be several days after you last had sex.

Or, he's just an arse.

How is the relationship apart from this?
It's very worrying that he seems to be accusing you of being unfaithful

40 weeks from 16th Dec is 21st September so that does match up.
It doesn't matter if you conceived 2 weeks later on 30th (or after), the estimated due date is worked out from the date of last period. So actually pregnancy is really around 38 weeks rather than 40 as the first 2 weeks are firstly period and then the days before ovulation and conception. Is this where your partner is confused?

Only 5% of babies are born at their calculated EDD.
I have no idea why we bother giving an exact date.
I think 'second half of september' is accurate enough and likely to be right

Or, yes, he's being an arse...

My EDD was a week different from what I knew to be correct. Gave birth at 39weeks according to my EDD but at 38weeks according to my dates.
Why is he questioning you? Were you TTC? Or last minute wobble?
Either way, it's a shitty thing to say

My due date with ds2 was way out, as I knew there was only one time when I could have conceived and it was no where near ovulation.

Then he measured big throughout my pregnancy, and arrived four weeks early. Made no sense at all.

Your partner sounds charming.

It's really weird for a man to question his partner and assume the baby isn't his. Is he always such a nasty bully?

Those dates sound right to me.

Your OH sounds delightful, effectively asking if you've been unfaithful by the sounds of things!

Thanks everyone appreciate it
We hadnt been together that long before I got pregnant so I understand he may have some concerns. But at the same time I don't just sleep around either!
Your support is appreciated xx

If your period started on the 16th and you had sex on the 30th, it's bang on ovulation time (14 days later). Unless you had an unusually long cycle.

He needs to educated himself in basic biology. Direct him towards the NHS pregnancy pages.

I hope he quickly gets over this.

Are there any other disagreements or tensions in the relationship?
Has he implied or accused you of cheating or lying before?
Has he shown any other signs of being paranoid and jealous?

It can take between 4 and 9 days for a fertilised egg to implant. Your dates are fine. Hope you resolve everything

I'm 26 weeks this week and according to my edd conception took place on the 1st January, (7th october) impossible really as i didnt have sex that day and its impossible for it to have been sperm from a few days before as I didn't have sex once that week as i was on my period. My dates gave me an edd of 22nd September.
I did a post when I found out my edd from my first scan and was basically told I'm an idiot and pregnancy is actually 38 weeks. I must be an idiot because I still don't understand and I've been hanging around these boards for a long time!

with dd2 I spent the whole pregnancy being told my dates were wrong, she must be 2 weeks younger. As dh had been away before and after I conceived, I was pretty sure I had the conception date correct.
I insisted that my notes had my dates on.

She was induced at 38 weeks for medical reasons and came out all covered in the white stuff which is unusual for 38 weeks apparently. Midwife looked and the notes and said 'Oh they must be right, she must be 2 weeks younger.'

I was too tired to ask how she could have been conceived without sex, and how I had then had a positive pregnancy test the day before they said she was conceived.

Well, biology is not an exact science
'Normal' pregnancy can be anything from 38 to 42 weeks - and some will fall outside those parameters.

Mother Nature can really be an awkward bint sometimes.