TheBump.com - the inside scoop on pregnancy.
Get The Bump magazine >
You're almost there. Log in if you're a member or join now to connect to Facebook.
Request a new password
popular: ovulation calculator
Find your most fertile days and start TTC >>
moms love: pregnancy calendar
Count down to delivery with your calendar >>
moms love: your baby this week
Sign up to receive weekly updates on your baby >>
moms love: baby name finder
Search through 1000s of baby names >>
moms love: personalized tickers
Track TTC, pregnancy, or baby's age >>
moms love: pregnancy week by week
Let us guide you along week-by-week!)
Since the "full gestation period" is 40 weeks, and separated into 3 sections/trimesters, a lot of people divide 40 by 3, coming up with 13.333... concluding that each trimester is roughly 13.3 weeks (roughly). So, the beginning of your 2nd trimester is 13.3 weeks, the beginning of your 3rd trimester is 26.7 weeks, and full gestation is at 40 weeks.
So, I guess the beginning of the 3rd trimester is somewhere around 26 weeks and 5 or 6-ish days? Maybe?
Anyway... Math! :D