March 2013 Moms

# Can someone explain trimesters to me?

I was always under the impression that you are considered in your second trimester at 12 weeks. Then I heard its actually when you are 14 weeks? In which case, when will be considered in our third trimester?

## Re: Can someone explain trimesters to me?

• member
Third trimester starts at the 27 weeks 0 days.  At least that's what I'm going by.

• member

Pregnancy is typically 40 weeks.  40 weeks does not divide evenly by 3, so the closest to making it even thirds is 14 weeks, then at 28 weeks, leaving the last 12 weeks as the third trimester.

TTC #1 since April 2010
BFP 4/18/12, M/C 4/27/12 at 6w6d
BFP 7/1/12 - Counting down to our little girl, EDD 3/8/13

• Really, each tri is 13.33 weeks.  Most people round and count the 2nd tri as starting at 13/14w and the 3rd tri as starting at 27/28w.

Here comes baby girl #2!
• member
I have seen it range anywhere from 26 to 28 weeks. I consider it 28 weeks.

• member

I'm going to jump in here with another numbers question. It seems like it should be simple, but for some reason I have a tough time wrapping my head around it. If I am, say, 24 weeks and 4 days...I'm assuming that means that 24 weeks and 4 days has passed, yes? Then is this considered "week 24?" Because wouldn't it really be week 25? I'm just thinking if the baby were 1 week, 3 days old, then it would be on "week 2."

Am I overanalyzing this?

• member

jennylyna:
Third trimester starts at the 27 weeks 0 days.  At least that's what I'm going by.

OMG - really?!  I'm so not ready to be in my 3rd tri!  This is going too fast

• member
Rhea77:

I'm going to jump in here with another numbers question. It seems like it should be simple, but for some reason I have a tough time wrapping my head around it. If I am, say, 24 weeks and 4 days...I'm assuming that means that 24 weeks and 4 days has passed, yes? Then is this considered "week 24?" Because wouldn't it really be week 25? I'm just thinking if the baby were 1 week, 3 days old, then it would be on "week 2."

Am I overanalyzing this?

If you are 24w4d, then that means you have completed 24 weeks & 4 days into your 25th week.

I consider the 2nd tri to start at 27 weeks.

04/07/11- PCOS Diagnosis w/GYN. Put on Metformin (1500 mgs)
04/25/11- 1st consultation with RE (Confirmed PCOS & Anovulation)
05/09/11-HSG-All clear! 05/13/11-SA-Normal. Found out on 2/14/12, low Morph (1%).
06/17/11-10 days of Clomid (100, 150) No response.
07/10/11-03/20/12- 5 Injectable (Follistim) IUI cycles; 4 BFN, 1 C/P. (stims ranged from 11 days to 25 days)
05/28/12-Diagnosed with Hypothyroidism. 75 mcg Synthroid.

IVF with ICSI in June/July 2013 = BFP!. Beta # 1 = 123. Beta # 2 = 252. Due March 25th. Baby boy arrived March 27, 2013!

FET #1 - 10/4/14 = BFP!! Beta #1 = 179. Beta # 2 = 499. Due June 22nd.

• member
Rhea77:

I'm going to jump in here with another numbers question. It seems like it should be simple, but for some reason I have a tough time wrapping my head around it. If I am, say, 24 weeks and 4 days...I'm assuming that means that 24 weeks and 4 days has passed, yes? Then is this considered "week 24?" Because wouldn't it really be week 25? I'm just thinking if the baby were 1 week, 3 days old, then it would be on "week 2."

Am I overanalyzing this?

No, it's so confusing!  And it's all semantics.  If you're 24 weeks 4 days, you're technically only 24 weeks pregnant, but you're halfway through your 25th week.  That's why I consider 27 (full) weeks to be 3rd tri - you're in your 28th week.  Who really cares at this point?!  We're all well on our way to baby!!

• 24w4d is 24 weeks completed and 4 days into 25th week.  I have always considered 13 weeks as 2nd Tri and 28 weeks as 3rd tri and 24 weeks as V-day but I'm noticing these vary from person to person.

Married 9/26/09 BFP #1 12/09 Blighted Ovum 12/23/09 D&C 1/10 BFP#2 5/1/10 DS born 12/18/10 38wks 10 lbs 1 oz BFP #3 6/25/12 EDD 3/5/13 RCS DS2 born 2-22-13 38wks 8 lbs 4 oz

• member
It's funny. As someone starting my 27th week now, I was curious if I was celebrating going into the 3rd trimester or finishing my 2nd trimester, as I love the little milestones along the way. It's so confusing because you can read sites that define the trimesters anywhere from 26-28 weeks.Then, my DH reminded me that there's only one milestone that counts...the day we have our LO! So, I'm sticking with counting down the weeks/days to the finish (or is it the beginning:)

• member
This has always been confusing to me too. If there are 40 weeks, divide by 3, which makes 13.33 weeks, which would make third tri begin on 26w6d. When I look at my bump due date calculator, it says mine start 12/8, which lines up with the 26w6d.  I'm going with that!
• member

jennylyna:
Third trimester starts at the 27 weeks 0 days.  At least that's what I'm going by.

I'm going by this too because this means I start the 3rd tri tomorrow, yay!

• member
All the math gets thrown off by the fact that you're not even pregnant for the first two weeks. So it makes sense that the 2nd tri begins at week 14, because at that point you have been truly pregnant for 3 months. Now I don't know what kind of crazy logic they are using for 3rd tri, but like PPs said who really cares? Smile.

• I am soooo confused by all of this.  Whenever people ask how far along I am I 1) usually don't remember, 2) cannot figure out which trimester I'm in, or 3) cannot convert my weeks into months.

I fear I will be equally confused with baby's age until our peanut is 1 year old!

Moya wanga u nhoxile!
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