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Sex of baby reveal at 3 month scan?

42 replies

Lotus8 · 04/05/2020 17:12

I had my dating scan at 13+4 days. The technition too a guess and I'm just wondering if anyone else found out the sex of their baby so soon and how accurate it was.

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lockdownpregnancy · 04/05/2020 17:25

Baby's genitals (whatever they are) are not fully formed at 13 weeks, so it would be really difficult to say at that stage.
It's usually from 16 weeks onwards that baby has everything formed for their gender, but easier at 20 week scan, as they are bigger in all matters of their development.
When I had my scan I was 13+1 weeks and baby is big (my DH is a big bloke) and she couldn't tell at that point.
Not sure what everyone else thinks x

Louise0701 · 04/05/2020 17:26

Agree with PP; not possible to tell so early on

Williams3001 · 04/05/2020 17:26

There's something called a 'nub' theory, which looks at the genital tubercle between the baby's legs. This is what will become your baby's genitalia, but because they haven't actually formed at this point, it's an educated guess of what the 'nub' will turn into, based on its angle. More accurate is either the Harmony test (private/paid for), which checks DNA or the anomaly scan (also called the 20-week scan).

NameChange30 · 04/05/2020 17:32

In my first pregnancy, the sonographer at my 12 week scan correctly guessed that it was a boy. I assumed that she'd seen the genitals but I have since heard that they are not formed at that gestation so if that's true, I don't know how she guessed!

I would have thought they'd be more inclined to guess if it looks like a boy - ie if they've seen a penis - whereas if you don't see one it might just be that you've missed it, rather than baby definitely being a girl.

(I am now pregnant with DC2, private scan at 16 weeks said girl, confirmed at 20 week scan.)

PrimeraVez · 04/05/2020 17:34

My OB/GYN said she had ‘an idea’ at my 12 week scan but refused to tell until I was 16 weeks when she was confident.

NameChange30 · 04/05/2020 17:35

And was her "idea" correct?

OnlyFoolsnMothers · 04/05/2020 17:45

I asked at my first scan for a best guess and they said boy but it was a girl at my 20wk (she was a girl too)! In the US they have a blood test at 3 months to determine, never understood why we don’t do that here.

butterflywall · 04/05/2020 18:09

I asked at my 12 week scan (I was 13+4) and she guessed boy. Said she was only 60% sure and didn’t want to say for sure but what she pointed out does look like it. I find out on Sunday 🙊

I think it’s easier to tell with a boy.

Sex of baby reveal at 3 month scan?
Minkies13 · 04/05/2020 18:45

I'd had the harmony test before my 12 week scan so I already knew I was having a girl. At my 12 week scan the Dr knew I already knew so she decided to see if she could get it correct. She got it correct.

Lotus8 · 04/05/2020 19:21

Very mixed outcomes.......I've just felt that he would have kept quiet if he wasn't confident but that's just me telling myself what I want to hear I guess. I think I'm going to drive myself mad over the next 5 weeks until my next scan, so might go ahead and have a private test. Am 16 weeks in a few days!

Anyone awaiting outcomes please update here. Very interested to know x

OP posts:
NameChange30 · 04/05/2020 19:23

So did the sonographer say girl or boy?!

Lotus8 · 04/05/2020 19:23

Fyi he said he thinks it's a boy and showed me on screen, 2 open legs with a sticky out bit

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GreyishDays · 04/05/2020 19:23

I was told girl at 16 weeks and then, correctly, boy at 20 weeks.

Lotus8 · 04/05/2020 19:24

NameChange30 he said Boy!

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Lotus8 · 04/05/2020 19:25

GreyishDays gosh how can they make such an error at 16 weeks!!

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NannyPear · 04/05/2020 19:30

The sonographer told my friend at her dating scan that she was pretty confident it was a boy (she was a bit further on than the usual 12 weeks; more like 14-16 weeks) and at the 20 week scan was told it was a girl, which it was! I think it's fairly common for female genitals to be swollen at that stage so easily mistaken for male. I wouldn't be convinced for now if I was you OP!

SuziGeo · 04/05/2020 19:55

My OBGYN told us at 16 weeks. He told us it would depend on the baby's position and if he wasn't sure he wouldn't tell us until 20 week scan. It was very clear at 16 weeks though that it was a boy.

AllTheWhoresOfMalta · 04/05/2020 20:01

I’m not a medical professional but ever since I heard about the skull theory it’s seemed to work very often! If you get a clear picture of the skull at 12 weeks but especially at 20 weeks it’s often pretty clear. I’ve used it for a lot of friends and relatives and I’m rarely wrong. I know it’s not fool proof and it depends on the picture but it seems much easier for a layman to determine that way than via the nub theory, where I’m never sure what I’m looking at.

Trying2b · 04/05/2020 20:02

With my first baby the sonographer said 70% girl at 12 weeks and was right! Second baby the sonographer guessed another girl (so I washed all the girl clothes and picked out girls names) only to discover 'she' had a winky at the 20 week scan hahaha!!

SunbathingDragon · 04/05/2020 20:03

2 open legs with a sticky out bit

Also exactly what girls look like because their genitals swell in the womb. It’s why mistakes are often made at much later gestational. If you want to know the sex at 13 weeks then have a blood test done and you will know conclusively.

Mummyme87 · 04/05/2020 20:03

@Lotus8 easily mistaken. I have met many a woman had it wrong at anomaly scan at 22weeks. Easier to mistaken boys for girls

NewName2020 · 04/05/2020 20:09

It's usually from 16 weeks onwards that baby has everything formed for their gender


We1shBird · 04/05/2020 20:44

Consultant doing the nuchal fold scan at 13 weeks said an experienced sonographer would be able to tell. He reckoned I was having a boy which turned out correct.

UrsulaSings · 05/05/2020 00:03

My sonographer at my 12 week scan when I asked if she could take a guess said 'they all look like boys at this stage to me!'

MichelleOR84 · 05/05/2020 08:12

My best friend was told at her 12 week scan that it appeared to be a boy and she did have a boy . But to fair , the sonographer had a 50\50 chance of being right

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