I am very confused about when I conceived the twins I am currently carrying. This is the facts I know. My LMP was 07/21/2010. I had sex with my husband between 07/25/2010 and 07/28/2010 unprotected and he ejaculated inside. I had just ended my period. We split up at the beginning of August and I was with an ex of mine on the late night of 08/04/2010. We had unprotected sex and he did "pull out." According to my LMP I am due 04/27/2010. When I went to my Dr I drew out a timeline for her ad put the dates I just gave and asked her what she thought. She said that according to my LMP it would be put it around 08/04. But then she looked at how far along I was during my ultrasound I had on 09/28/2010. I was 9 weeks and 5 days along. She used her pregnancy wheel and should me that 9 weeks and 5 days would bring it right about to 07/28/2010. She said that the LMP is "textbook" guesses that don't always apply. Especially when my cycle is as irrregular as it is. My Dr did say that she would feel completely comfortable in saying my husband is the father. I am still very nervous though and really want to know. My husband and I are back together and trying to make our family work but if the twins are not his I donot see us working... please any input will be appreciated =)

If your LMP was 7/21, you most likely conceived on or around 8/4 according to my gestation wheel. It's the same one your doctor uses.

I do feel that your husband MAY be the father of the baby (FOB) since it takes a few days for the sperm to reach the egg, however, this does not replace an actual DNA test that will need to be done to prove paternity.

Thank you for your response. My Dr did it based on LMP at first. But that conflicted to how far along my ultrasound said I was. She said at ultrasound that was done on Sept 28, 2010 I was 9 weeks and 5 days. She said that would have put conception back a little? Since everyone's cycles are different and many women do not ovulate according to LMP

Unfortunately, it's all going to have to come down to a DNA test. There is no way to tell exactly when the egg "met" the sperm.