Confusion over trimesters

[Chellepot]

Hi Ladies,

After having my dating scan today I have found out I am a week futher along than originally thought. I updated my tickers and one of them says I am now in the 2nd tri. Its not the first time I have seen the 2nd tri published at 12 weeks as my pregnancy book also states 12 weeks as the start of the 2nd tri but on BnB its 14 weeks. Does anyone know what the actual medical trimester definitions are? I'm really not sure what trimester I am in now

 

[Newbie Mommie]

I had the same question too as I got confused about some fellow BnBers stating that 14 weeks was the beginning of their second trimester. Since 9 months divided into three equals 12 I got super confused. What it comes down to is a pregnancy actually lasts for about 10 months. Anyway, I did some research the other day and this is what I found:

"The word trimester means "three months." This is often a source of confusion, because a normal pregnancy is 40 weeks, a tad longer than nine months. Nevertheless, health care providers and pregnant women talk about three trimesters to help give pregnancy a beginning, middle, and end. Most providers actually talk about your pregnancy in weeks, rather than months or trimesters.

Most commonly, the first trimester is defined as from conception through week 14. The second trimester is from week 14 through week 28. And the third trimester is from week 28 through labor and deliver, which varies considerably but averages at week 40."

https://www.pennmedicine.org/health_info/pregnancy/000006.htm

I also read that the second trimester can technically begin at 13 weeks and 3 days since that would be the entire length of the pregnancy divided by 3. I plan on counting myself as being in the second trimester at that time.

I hope this helped and wasn't too wordy (or mathy...I hate math)!

 

[libbymarks198]

its beacuse you are pregnant for 10 months not 9

 

[AP]

27 weeks is the start of 3rd tri, defo, i was always told i only just made 3rd tri with my LO when she was born

 

[Chellepot]

I also read that the second trimester can technically begin at 13 weeks and 3 days since that would be the entire length of the pregnancy divided by 3. I plan on counting myself as being in the second trimester at that time.

I hope this helped and wasn't too wordy (or mathy...I hate math)!

I think I might go with this one too, i'm closer to 13w3d than I am 14 lol! That way I get to be in 2nd tri sooner

 

[AP]

Madness - i had a google and all i got was 28 weeks! So I didnt even make it there!

 

[Katie Mc]

its always been 12 weeks to me until I came on here

 

[Lilly12]

its always been 12 weeks to me until I came on here

Same here!

 

[emilyjade]

tbh just go over when you feel like your ready and the threads over here and been done so many times and no use to you anymore lol! good luck !!

 

[Chellepot]

its always been 12 weeks to me until I came on here

Yeah I was the same. I've always gone by the wait 3 months to tell family etc cos you are passed the greatest risk of MC rule, not that I did that. I told my family quite early on. If my maths hasn't totally failed me 4 weeks = 1 month, 12 weeks = 3 months. I think i've just confused myself even more now

Ok I am officially in the 1st and a half tri!

 

[mummy2be123]

I always thought it was 12 weeks until I come on here myself. I'd say 12/13 weeks now and change tri when you feel right to it doesnt matter

x

 

[Ang3l]

Im confused as well, I don't understand it. In a couple of pregnancy books that I have as well as this website and a couple others it says that the 2nd trimester starts at 14 weeks. However in some websites, mainly UK ones, it says 12 weeks is the start of the 2nd trimester! And again in one website I read it was 13 weeks!

What on earth are we supposed to think! :S

 

[Chellepot]

Yes there does seem to be discrepancies between US and UK sites with regards to a lot of things. I was looking at herbal teas and some of the ones the uk sites said were fine the US sites said should be avoided...

 

[AP]

Weird, look what Bupa says https://hcd2.bupa.co.uk/fact_sheets/html/pregnancy_what_happens.html

 

[Lamsbump]

its always been 12 weeks to me until I came on here

Me too but im going to officially move over at 13.3.

 

[Tigerlass]

I get confused about this aswell but I decided I'm just going to move over when my ticker says so and when I feel ready lol.

​

 

[BrandiCanucks]

40/3=13.333333333333....

Second Trimester begins at 13w3d