~42 weeks prior ... look at a calendar and you will be able to figure the approximate date out.
Copy and paste this link into your address bar. You can calculate your conception date using the conception calculator on this webpage. http://www.baby2see.com/conception_calculator.html#ConceptionCalculator
13th January
The approximate date of conception was February 3rd
The approximate date of conception was May 11th 2009.
February 13th 2010 (give or take a few days)
Roughly April 20th
Based on a normal gestation period of 40 weeks the conception date was August 20th.
The approximate date of conception was May 13th 2009
The approximate date of conception was September 1st
The approximate date of conception is May 20th
If July 20th was calculated as your due date early in your pregnancy the date calculator works. However if your baby was born at term on July 20th and you are working backwards from that date you could be 2 wweks out either way.
The approximate date of conception was May 25th