Expert: Dorothy H, LCCE - 7/14/2010

Question
QUESTION: hello, this is very difficult times for me, my wife is now about 32weeks, we are divorcing and havent spoken for months, i was involved with the pregnancy untill we split and have dates but am still unclear of paternity of the child. last lmp was 11-27-09(irregular)before that was 10-21-09,we had sex on 12-14,15 and 16-09, transvaginal u/s at 5w5d on 1-13-10 gives due date of9-10-10, transvaginal u/s at 9w2d on 2-5-10 gives due date of 9-8-10. Unfortunately she has a addiction(reason for divorce)and i threatened to take the baby unless she cleaned up, after that she said it was not mine, she was gone for one week prior returning on 12-12-09, i have to assume the worst and say she made her mistake on 12-11-09, ultimately my question is, is this OUR daughter ? nervous, scared, and stressed, thank you for your time

ANSWER: Based on the information given, she became pregnant in mid-December.  Because she is saying she had sex with two different men during the time period when she could have gotten pregnant, either of you could be the father.  It could go either way.

The only way you will know for sure is to have a paternity test done after the baby is born.  I'm sorry I can't give you a more definitive answer.  I hope you get the answer that you are looking for.



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QUESTION: thank you so much for your rapid response, in regards to my previous question, can i possibally have your opinion as to when she could have ovulated and or concieved? i really hope this child is mine and from my research given the situation it is.. then again im am looking for ways and reasons to believe it is mine, although i do understand that there is a 50-50 chance, it either will be or it wont be, i also understand that anything you tell me or anwser for me is just an opinion based on your expertise. im looking for possible conception/ovulation, accuracy of ultrasounds for gestational age, can due dates changes(i understand the baby comes when its ready, maybe early or late)and an embarrassing one, would my fresh semen be more likely to reach the egg while older semen exist?  again, thank you for your quick reply, any information im sure would be a great help

Answer
I think there is a good chance that the child is yours.

According to the ultrasound, it looks like she probably ovulated between 12/15 - 12/17. First trimester ultrasounds are generally accurate within two days, especially with two of them.  Sperm can easily live 3 days, sometimes 5, and the egg can live 1 day.  So any sex that she had from 12/10 - 12/18 could have resulted in a pregnancy. You had sex with her three times during that time period, which makes it a high probability that you are the father. However, if she had sex with another man during that time period, there is a possibility that he is the father.  

Due dates can sometimes change by a couple of days, like with the differences in the ultrasounds.

When the baby is born won't tell you when she conceived, as a normal pregnancy can last anywhere between 37-42 weeks.

With the semen, it doesn't make a difference. It all depends on whose sperm was there when she ovulated, and which sperm got there first.

I would strongly suggest getting a paternity test done ASAP when the baby is born.