Calculate Your Conception Date: Understanding Gestational Age

Question
Hi, i will be 23 weeks pregnant as of tomorrow April 11th 2008, my current due date is Aug 7th...im tring to figure out what month i got pregnant in...if i count back 23 weeks from today i go back to october but if i use this tool i found on the internet i get november 13th...please help me :(?

Answer
I'm coming up with a conception date between November 12-14th. I believe the confusion is between the gestational age and the pregnancy time. Pregnancy is calculated from the LMP or Last Menstrual Period. So your LMP WILL go back into October as you generally ovulate 2 weeks after the first date of your LMP. Even if you have irregular periods, it's calculated when your LMP should have been based on when you most likely ovulated/conceived. So while you're 23 weeks, your baby is only about 21 weeks gestation.

Please let me know if I can help you further or with anything else.

Best wishes,
Helen =)