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Readers Respond: How do you calculate the months of pregnancy?

Responses: 3


Updated June 08, 2011

280 days, 40 weeks, 9 months, 3 trimesters... it can be confusing, but nothing is as confusing as trying to calculate the months of pregnancy.

Some people calculate from the moment of conception, others start at the first day of their last period. Sometimes it's a quick math calculation of how much time your have left in pregnancy and some moms don't ever bother with months.

So how many months is 26 weeks? What about 13?


I was told that you figure out the months by taking how many weeks you are (like say 17) and dividing it by 4.3 (thats the number of weeks in an average month) so at 17 weeks you would be 3.95 months pregnant.

Skip the first two weeks...

Since I'm not really pregnant those first two weeks, I usually say I'm one month pregnant until I'm six weeks and go every four after that.
—Guest Mom2BabyG

It depends on my mood...

I know it sounds crazy but how I calculate months depends on my mood. If I'm enjoying pregnancy I usually calculate lower months but if I'm tired or hurting, I calculate higher. I also have been known to calculate higher to seem very pregnant, you know, someone asks me to do something I'm not sure I want to do like attend a function, so I say "Oh I'm 8 months pregnant, I don't know..." As opposed to saying I'm 33 weeks or something.
—Guest Treya
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