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Original poster

Question about pregnancy for any Americans here

31 replies

HollowTalk · 02/09/2019 13:57

Over in the UK we date a pregnancy from the start of a woman's last period, so if she's a week late, she's considered to be five weeks' pregnant.

Is it the same over in the US? I am writing something for the American market and this has been picked up by my editor and my copy-editor - they seem to date a pregnancy by the date of conception. Is this what happens over there?f

Please help!

OP posts:
Original poster
HollowTalk · 02/09/2019 13:58

Please ignore the random 'f' - just reading something Boris Johnson said and can't stop swearing.

OP posts:
Caterina99 · 02/09/2019 15:06

It’s the same as the Uk

Original poster
HollowTalk · 02/09/2019 15:09

Thanks, @caterina99. I've found sites that say that, too. I just don't know why it was queried by two different people. Thanks, anyway!

OP posts:

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Families
Caterina99 · 02/09/2019 15:12

Yes had 2 babies here. Definitely dated from the first day of your last period

ChristmasArmadillo · 02/09/2019 15:15

It’s the same.

SecretWitch · 02/09/2019 15:17

3 babies born in the US. All my pregnancies were dated by first day of last period.

Original poster
HollowTalk · 02/09/2019 16:10

Thanks - this is very reassuring!

OP posts:
mindutopia · 02/09/2019 16:10

It's definitely dated the same as in the UK, but a lot of people don't understand it anyway, so it's no surprise if your editor and copy editor aren't experts in this area. The average lay person probably doesn't know that either until they have a baby.

pallisers · 02/09/2019 16:12

3 babies born in the US. All my pregnancies were dated by first day of last period.

exact same here.

StrawberrySquash · 02/09/2019 16:34

What is the logic for dating this way?
If you don't have a regular cycle does it have any consequences in terms of understanding if you actually need to be induced or not because you are considered at 42 weeks?

pallisers · 02/09/2019 23:30

I think the logic is most people don't know the exact date they conceived (even if they had sex on only one day, conception might have occurred a day or so later). But they are more likely to know the first date of their last period. It doesn't really matter if the cycle is irregular or not - it gives a decent starting point of about 2-4 weeks.

mathanxiety · 03/09/2019 05:45

You are right, StrawberrySquash, there is no logic to it. It is a practice based on an assumption that all women have regular 28 day cycles.

So an estimated delivery day can be off by up to a few weeks in some cases, and yes, there are consequences wrt induction.

Many MWs and OBs in the US will run tests to try to get a better handle on gestational age. Many will go strictly by the calculation based on LMP however.

Your editor and copy-editor are eejits to assume date of conception is something that can be pinpointed though...

mathanxiety · 03/09/2019 05:46

Last remark addressed to the OP. ^^

HerSymphonyAndSong · 03/09/2019 05:49

Mathanxiety that’s interesting do they continue to use LMP throughout the pregnancy then? In the UK your due date may be adjusted by a dating scan at what is assumed to be 12 weeks and they will go from that date from then on

Veterinari · 03/09/2019 05:51

What is the logic for dating this way?
If you don't have a regular cycle does it have any consequences in terms of understanding if you actually need to be induced or not because you are considered at 42 weeks?

Absolutely! My cousin knew when she’d conceived to within a couple of says as she’d Only had sex once in that timeframe. However because of this dating method she was considered ‘overdue’ and pressured to have two sweeps to try a start her ‘overdue’ labour. Fortunately she went into labour naturally when they were starting to make noises about inducing her - madness that they’d focus on their own inaccurate dating!

LoreleiRock · 03/09/2019 05:58

Probably should start my own thread, but why do Americans put hats on newborns immediately after birth?

pushpushglide · 03/09/2019 06:04

I'm in UK and both of my dc (born at different hospitals) had hats put on by midwife pretty much straight away so may not be just an American thing.

LoreleiRock · 03/09/2019 06:07

Why?

HerSymphonyAndSong · 03/09/2019 06:10

They worry about newborns getting cold and a lot of heat is lost from the head. It’s pretty normal in the UK too

LoreleiRock · 03/09/2019 06:16

The same amount of heat is lost from all parts of the body, so why do you see brand new naked babies with a hat plonked on? Skin to skin is more common in UK to regulate body temperature of newborns.

HerSymphonyAndSong · 03/09/2019 06:21

I don’t know, I did skin to skin without a hat on. It’s still completely normal for midwives to put hats on in the UK so this is not a US thing. Why not start a separate thread and maybe midwives can explain their reasoning?

LoreleiRock · 03/09/2019 06:23

I googled after I wrote. It is not generally done in UK, but also seems to be falling out of favour in the US too.

BernadetteRostankowskiWolowitz · 03/09/2019 06:24

They only use last period until the dating scan in the UK. Once the dating scan is carried out they will use the measurements to give a more accurate due date.

LoreleiRock · 03/09/2019 06:24

And it is about heat, which is why it has fallen from favour.

HerSymphonyAndSong · 03/09/2019 06:25

Well there you go then Smile