Very confused re: 1st Trimester--- with 2 questions

So, logical thinking-- and what I have always thought-- says that 12 weeks is the end of your first Trimester, as 12 weeks is 3 months.

Then, I find that you're second trimester does not really begin til weel 14. Ok.

Now, I am looking at this chart which based on my due date (2/2) says that 12 weeks is the end of my first trimester.

So, when is it???

And-- the real reason for my question... for those waiting to tell people-- did you wait til 12 weeks or 14 weeks?? I always had it in my head as 12, why not wait til 14 if that's what I am waiting for, ya know?

Re: Very confused re: 1st Trimester--- with 2 questions

I think at 12 weeks the chances of miscarriage are reduced to a very minimal percent and that is why people wait that long.

Re: Very confused re: 1st Trimester--- with 2 questions

I think 12 weeks is when your first trimester ends not 14 weeks.

Re: Very confused re: 1st Trimester--- with 2 questions

Your 2nd trimester starts at the beginning of the your 14th week.

Your 3rd trimester starts at the beginning of your 27th week.

Message edited 7/4/2008 9:00:12 AM.

Re: Very confused re: 1st Trimester--- with 2 questions

Well if you divide 40 (weeks of pregnancy) by 3 (to get trimesters) you get a 13.3

I prefer this calendar to all others

Calendar

Re: Very confused re: 1st Trimester--- with 2 questions

There are 3 ways that first trimester can be determined: by gestation, by conception and by development. This is according to a calculator I found. Each one will give you different dates.

But on average, it really is the 13th week that starts the second trimester.

I waited until after 13 weeks to tell people based on this. I didn't come out on this board until almost 14 weeks based on this as well.

Message edited 7/4/2008 9:16:17 AM.

Re: Very confused re: 1st Trimester--- with 2 questions

i hear ya - i had the same question. A lot of diff sources say a lot of diff things. I think the end of the 12th week is the end of the first tri

Re: Very confused re: 1st Trimester--- with 2 questions

My doctor told me a woman is considered in her 1st trimester until the 14th week.

Re: Very confused re: 1st Trimester--- with 2 questions

After your 13th week is complete, you have finished your first trimester.

Re: Very confused re: 1st Trimester--- with 2 questions

My doc says after the end of the 13th week you start the 2nd tri. This is why they do the first tri screening/ultrascreen up until 13w 6d. I agree with jen on the risk of mc going way down after 12 wks, which is the reason for waiting but I think ppl assume its the end bc of the three month thing

Re: Very confused re: 1st Trimester--- with 2 questions

when you finish your 12th week, you are entering the 13th so that is why some people wait until 13
ive never heard of 14

Re: Very confused re: 1st Trimester--- with 2 questions