When does the third trimester start?

[MyHeadIsAMinefield]

I use a pregnancy app to track how many weeks I am. It's telling me today I am 26 weeks and have just entered third trimester. I thought trimester 3 started at 28 weeks?

Confused... anyone?

I thought first week of third trimester was 27th week. So you are in the last week of the second trimester. #helpful

Oh I've googled and Bupa agree with you. My app says 27-40 is third trimester. I wonder if it's an American app, do they count differently over there? Sorry I'm confusing matters! :grin:

I'll take the happy medium and presume it starts next week thank you!

To throw a spanner in here, when do you become for example "6 months pregnant"? I have been adding on months since my last period but my app says 23-27w is the 6th month

@Italianshark would you just count exactly 6 months from the date of conception? So say if that was 1st January you'd be 6 months on 1st July? It's bloody complicated isn't it lol! Not that any of it matters in the long run!

There doesn't seem to be any official consensus, I just counted 3 months back from my due date. Or 26 weeks is exactly 6 months (half a year).

Italian the sixth month is anything from 5 months + one day to 6 months exactly. Being six months comes at the end of the sixth month.

I always thought that the 3rd trimester started at 28 weeks, but I considered 6 months pregnant to be 3 months before my due date.

...but you're right OP, not like it matters. Babies don't care about due dates haha

The months don’t really make sense. It’s confusing because some months have 4 weeks, some have 5 so it all adds up. I never know what month I’m in tbh so just guess. I’m 26 weeks now and would say I’m six months pregnant but I think it’s technically still the fifth month until 28 weeks . AFAIK third trimester starts at 28 weeks.

You can just go by the calendar date to work out months. So if you're due on the 5th, each 5th of every month you're one month more pregnant. Count backwards from 9.

Regarding months I count backwards from my due date. I'm due at the start of October, so I'm nearly 7 months pregnant as I have two left.

the 3rd trimester officially starts between the 27th and 28th week of pregnancy