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Can the scan dates be wrong?

(7 Posts)
user1493407412 Fri 28-Apr-17 21:05:48

Hello, I hope someone can help me with this please. Basically scan shows I'm 16 weeks so works out at around 5th of January but the only times I had sex over that time was 16th December and 14th January. My periods have been irregular since having my daughter but had slowly been getting back to normal, even though I would sometimes miss a cycle when they did come they'd always be around the end of the month sometimes going into the next. I had a short/light bleed maybe spotting on 1st Jan to 3rd Jan and this never happened before as my periods have always been 8 days long every time. It was also at the time of the bleed I started having pregnancy symptoms like sore breasts, emotional and bloating ect. but if I was pregnant at this time I'd be further along. My question is when would I have gotten pregnant? Could the scan dates be off? Thanks for any help

ChickenBhuna Fri 28-Apr-17 21:10:51

Your last period would've been around Jan 5th. You would've then ovulated around Jan 14. All makes perfect sense OP :-)

Fairy45 Fri 28-Apr-17 21:11:53

Hmmm, i got bfp 29th jan last lmp 23rd dec and in 17 weeks but i had thought i conceived around 14th jan when my ovulationstick said peak. But if you put in google it says i conceived 30th dec but i was still on and not dtd then! Hmmm think google is wrong and scan dates correct and dont worry too much about that!

ChickenBhuna Fri 28-Apr-17 21:12:46

Sorry I only skimmed your post , the time you had sex in Jan would basically be around the time you ovulated. Don't worry about the other date.

GreenGoblin0 Fri 28-Apr-17 21:29:08

the 16 weeks is from the first day of your last period not the date you conceived. this ties in with when you bled in January give or take a few days so you would've conceived after you dtd on 14 Jan

Emma2803 Fri 28-Apr-17 22:48:44

As previously said doctors date of egg being fertilised plus two weeks as in the "average" cycle the egg is released two weeks after the start of the period so this make it easier to work out the due date.

Also the day you have sex is not necessarily the day you conceived as the sperm live for a few days inside the woman's body but the egg only lives for one day so it's perfectly possible that you had sex on 14th and the sperm were still alive and kicking on the 19th when your egg was released and then fertilised!!!

Scan sounds spot on to me!

haveacupoftea Sat 29-Apr-17 00:12:29

Yep lots of people think they know when they conceived and scan dates must be wrong and don't factor in the +2 weeks and the fact that you can never know exactly when you ovulated and conceived, all you can glean from OPKs etc is a rough idea. Scan dates are very accurate around the 10-12 week mark.

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