How many weeks

[Olivepearl]

Hi all, this may be a silly question , but when you say how many weeks pregnant you are, how do you work this out? Do you go from the first day of your last period or from when you think you ovulated? Im 7 weeks today (from 1st day of period) but should I really be saying 5 weeks of I know I ovulated on 10th December?

im really anxious as I was told I probably couldn’t have a child and now worried about a chemical/development etc. it feels like so much can go wrong.

from the first day of your last menstrual period

Initially, your midwife will work it out from your LMP so you will be classed as 7 weeks pregnant - this is based on an average 28 day cycle with ovulation on exactly day 14 and isn't accurate for everyone (although it sounds pretty close in your case).

When you have your 12 week scan (aka dating scan) this will give you your official due date which may vary slightly from what your LMP would put you at. From this point, the LMP date is no longer used and your actual scan measurements and due date are what they go on.

Pregnancy is worked out as when you ovulated plus 14 days - if you know you ovulated 5 weeks ago then you would add the 2 weeks on to that which would make you 7 weeks pregnant so it's very much inline with your LMP date.

First day of your last period until your dating scan then the date gets adjusted but it's still adjusted so that roughly the first two weeks are prior to the egg getting fertilised.
Fur example you might have your dating scan at 12 weeks 4 days based on lmp but you are measured ahead by a few days at 13 weeks 0 days. From then on you use that date for counting and for your due date. Then you get to 9 months and there's suddenly a 5 week window in which you might give birth in!

This is a nice and easy tool

www.nhs.uk/pregnancy/finding-out/due-date-calculator/

Thank you everyone, this has really helped me x