2nd trimester

Any idea why second trimester start at week 14 instead of week 13? 1 month consist of 4 weeks isnt it?

2nd trimester
1 Reply
undefined profile icon
Write a reply
Super Mum

Each month has 4.5 weeks on average, so I think this chart gives an estimate based on that. But generally, I think most of us consider weeks 1-12 as 1st trimester