Are you confused about which stage of pregnancy you're in? See the pregnancy chart below to see how we calculate the length of each of the stages of pregnancy~ weeks-months-trimesters.
Have you wondered how many weeks are in each trimester? My pregnancy stages chart will show you how ThePregnancyRealm.com figures how many weeks are in each trimester.
No more guessing which week you are in when you read a page about the weeks-months-trimesters of pregnancy for the correct stage you are in.
Use the stages of pregnancy chart below to help you determine how I calculate the stages of pregnancy for this website which is how most practitioners calculate it also.
Click chart to make larger
The average length of a pregnancy is 40 weeks starting at the first day of your last menstrual period.
The stages of pregnancy can also be broken down by months. There are 9 months and 1 week in an average pregnancy duration. The 9 months alone are comprised of 39 weeks (1 week short of 40) which is why the extra week is added. Even though most people just generally refer to the pregnancy length as 9 months.
And then there are the trimesters containing 3 months each during a normal pregnancy term. The third trimester is one week longer than the first and second trimesters.
Of course, these are only averages. Every pregnancy and every 'body' are different. Two weeks before and two weeks after the 40th week are considered normal full term pregnancy terms.
As shown in the pregnancy chart above, there are 13 weeks in the first trimester -- week 1 to week 13. The first trimester begins with the first day of your last menstrual period (LMP) and ends at the end of week 13.
The 2nd trimester also has 13 weeks -- week 14 to week 26. The second trimester starts at the beginning of week 14 and ends at the end of week 26.
The third trimester is one week longer than the first two. It has 14 weeks from week 27 to week 40. The 3rd trimester starts at the beginning of week 27 and ends at the end of week 40.