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How to date a pregnancy?

(24 Posts)
EastDulwichWife Mon 25-Sep-17 10:55:27

We got our BFP on Saturday and we're absolutely delighted. Struggling to work out how many weeks I am though, because since having the IUD out, I haven't had a period. The coil was removed on Sep 1st, and I'm pretty sure we conceived on September 8th.

I took three tests on Saturday as had been having some hot flushes and cramping, and all three came back with bright pink lines immediately!

If we conceived on the 8th, am I 3w+3, or do I add 2 weeks on (as the Dr would), and be 5w+3.

I'm confused since it seems unlikely to have had such strong positives at just 3 weeks!

Any help at all would be hugely appreciated!

EastDulwichWife Mon 25-Sep-17 10:59:51

Sorry - should add, that the 3+3 date is based on the date of coil removal... x

justtheonethen Mon 25-Sep-17 11:00:01

Congratulations! If you think you're 3weeks since conception then you're 5 weeks pregnant.

BertieBotts Mon 25-Sep-17 11:03:12

Don't worry too much about it, take the latest possible date (ie most number of weeks) and it will get updated/adjusted at your first scan. Better to think you're further along and get corrected to earlier than the other way around as you can miss things. Just explain this to anyone who's doing any kind of measurements.

EastDulwichWife Mon 25-Sep-17 11:11:47

Thanks both. We are on a self referral system here and as it's our first I'm so nervous and unsure about everything!

Using your logic just, I'll assume I'm 5 weeks on Thursday. That'll help my worries at least, as I was worried about chemical pregnancies, etc.

Thank you!

justtheonethen Mon 25-Sep-17 11:22:08

If you think you conceived on the 8th then you should be 4+3 actually but like bertie says don't worry too much as the dates will get corrected at first scan.
Congrats again!

justtheonethen Mon 25-Sep-17 11:22:40

Which is what you said! Sorry!

nodogsinthebedroom Mon 25-Sep-17 11:30:11

If you think you're 3weeks since conception then you're 5 weeks pregnant

As a non pregnant person - wtf?!

Could someone please explain this to me?

(OP - sorry to derail)

justtheonethen Mon 25-Sep-17 11:35:36

nodogs The development of pregnancy is counted from the first day of the woman's last normal menstrual period, even though the development of the fetus does not begin until conception, which is about two weeks later.

Stolen from tinternet obviously smile

justtheonethen Mon 25-Sep-17 11:35:53

Hence weird bolding! Sorry!

justtheonethen Mon 25-Sep-17 11:36:49

Basically it's counted from the start of your cycle which has normally begun two weeks before ovulation.

Orangebird69 Mon 25-Sep-17 11:37:01

nodogs pregnancy is dated from the 1st day of your last period - ovulation/conception usually takes place 2 weeks...

EastDulwichWife Mon 25-Sep-17 11:39:44

Thanks just! Great stuff, I'll assume that and hopefully will be seen within the next 4 weeks.

Nodogs - not at all! I'm glad someone else is as puzzled by it as I am! grin

In a real state of shock at the moment. After telling my DH to relax ("It'll likely to take 6 months, if not longer"), we're both astonished to be upduffed within 3 weeks!

justtheonethen Mon 25-Sep-17 12:40:39

How lovely. To be fair I was still in shock and it took 3.5 years and ivf grin. Still had that "what the fuck" moment!

I'm just down the road from you, if your name is a clue!

gandalfspants Mon 25-Sep-17 13:12:47

If you conceived on the 8th you're 2 weeks 3 days after conception, so 4+3 given the way they date. With cool removal on the 1st making you 5+3 at the absolute most.

Tell them all this when you phone. Or just say 'about 5 weeks'. I told the woman on the phone that my clearblue said 2-3 weeks and she just wrote 2-3 weeks, so my booking in app was at 10 weeks instead of 8 and my '12 week scan' was almost 'too late' and had to be pushed forward when my midwife realised the cock up.

(My periods were messed up and LMP would have made me 4 months!)

lampert Mon 25-Sep-17 13:18:39

I think I conceived on the 8th too @EastDulwichWife

Unfortunately that puts me 4days behind where calculating based on my LMP did so I feel frustrated today that I am no longer 5 weeks today but instead 4 + 3! Wahhhh!!

I think time has stopped. I think the 6 days since my BFP last Tuesday have been the slowest ever!!!!

Mrstobe90 Mon 25-Sep-17 13:26:44

My positives were very strong at 5 weeks so it is possible 😊 congratulations!

justtheonethen Mon 25-Sep-17 13:29:53

lampert they will go by your last period so you are 5 weeks today! The op didn't have one to date it from and is going from coil removal. Just be prepared to be put back or forward a few days at your scan!

lampert Mon 25-Sep-17 13:36:33

Thank you @justtheonethen

I have 31 day cycles (ish - they vary slightly each month but my app says 31) and I know I ovulated late (on CD19) as I was doing opks.

We only dtd on the 7th and & 8th so that must be when it happened but should I still use my LMP? That would surely assume a 28 day cycle and ovulation at day 14? I am sorry, I'm prob being stupid and totally overthinking. I've read too much and feel completely scared, a bit overwhelmed and rather confused!!!

I wish I could fast forward to the 12 week scan!!

justtheonethen Mon 25-Sep-17 13:39:10

The doctor/midwife will date it from your period but you won't be surprised if you're a few days behind at your scan!

justtheonethen Mon 25-Sep-17 13:39:37

Congratulations by the way!

EastDulwichWife Mon 25-Sep-17 14:03:32

Thanks so much everyone! Overwhelmed by the (very helpful) responses..!

Just Really!? If you fancy a decaf coffee at any point, let me know.. smile

I've self referred already so should hear back from the hospital on Wednesday, at which point I'll let them know that I've calculated my dates incorrectly.

justtheonethen Mon 25-Sep-17 14:06:51

Yep, about 10-15 mins away. That would be lovely! PM me if you like smile.

lampert Mon 25-Sep-17 14:52:52

Thank you @justtheonethen!! Really appreciate your help!

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