I will assume you are talking about December 18th 2011. If so, your estimated date of conception is March 26th 2011. This date is give or take a couple of days though. It should not be relied upon to determine paternity.
December 26
The approximate date of conception was April 27th
Based on a normal gestation period of 40 weeks the conception date was March 27th
Based on a normal gestation period of 40 weeks the conception date was August 25th.
The approximate date of conception was January 1st
The approximate date of conception was October 25th 1999
The approximate date of conception was June 23rd 2009. The start date of your last menstrual period is estimated at June 9th 2009
The most likely day of conception would have been February 17th, and Based on a normal gestation period of 40 weeks the due date is November 10th.
Sometime around Late August-September.
if u are 20 weeks lmp you got pregnant 18 weeks ago so count back 18 weeks but if u want a date u need to give due date or lmp
March 18, 1946
Roughly September 22nd 2009, give or take a few days. However, it is difficult to accurately say when a conception date is. Therefore, I suggest talking to your doctor, midwife or obstetrician about it.