134578 tn?1614729226

FAQs -- Who is my baby's father?

Ways to Try To Identify the Baby's Daddy

If you are pregnant and wondering who the father of your baby is because you had sex with more than one guy, here is a list of things to do to try to figure it out, based on what women writing in to the DNA/Paternity community have found useful. They are in order of time, in that if one doesn't answer the question or it's too late to do it, move on to the next. You can also write in with your dates and data and see if someone here can help you figure it out.  :)

1 - Regarding trying to figure out who the dad is by working out when ovulation might have been -- a lot of women believe that ovulation happens 14 days after the first day of their prior period. For some women this might be true, but unfortunately, that concept is reliable only if her periods are like clockwork every 28 days without ever varying by even one day. The period is not a starting point but an end point, ovulation is the start point in the process, which ends in a period if the woman is not pregnant. Then it can be any number of days or weeks before a woman ovulates again. If a woman always has totally reliable 28-day cycles from period to period, the conventional "14 days after the last period" might be true, but if her cycles vary, it might not.

The other problem with assuming conception was 14 days after the last period is that while the woman's egg lasts only about 24-36 hours if it is not fertilized, men's sperm can last in the woman's body 4-6 days. This means sex a certain number of days before the assumed ovulation can produce a pregnancy.

2 - If trying to decide when ovulation was is impossible, the woman should go to the doctor as soon as she realizes she is pregnant, and take along a list of the dates she had sex. The ideal time to go is at 6 or 7 weeks from the first day of the last period. She should get an ultrasound at that appointment, and ask the doctor to help her understand when she conceived. Whether she gets an ultrasound or not, she should tell the doctor that she needs help determining when conception was, using the actual c-word ("conceived,") not just "How far along am I?" If she words the question as "How far along," she is likely to get an answer from the doctor based on a gestational-age count (which all doctors use but is frankly pretty useless, since gestational-age counts do not begin when one conceived. Gestational-age counts start on the first day of the last period, not on the day of conception, for historic reasons. It doesn't make sense in this day and age of ultrasounds, but they still do it.)

At the doctor's, the woman should explain her dilemma and the dates when she had sex with whom, and see if the doctor can advise her about who is the dad. If the dates are too close to call, the doctor will say so.

3 - If the doctor does not offer an ultrasound at the first appointment, the woman should bend all efforts to get one by her 7th week (counted, again, from the first day of the last period). It is the best way to find out at this stage, and this is a window that will close soon. Using an ultrasound to date conception gets less accurate as time progresses in the pregnancy. If the doctor simply will not order an ultrasound, it's important enough that it might be worth getting a new doctor. Once the ultrasound is done, the woman should ask for an estimated due date based explicitly on the measurements of the embryo and not on the first day of her last period. (She is asking for a calendar date, like "June 29," not a statement like "6 weeks pregnant.") She can then take that due date home and either count back 266 days from it on a calendar, or put it into an online conception calculator, to get an estimated date of conception.

4 - If it is too late for a date to be reliable from an ultrasound (most doctors will say "give or take a week" if the ultrasound is even as far along as the 12th week after the last period, which makes this a time-sensitive issue), the next available way to try to find out is by doing a DNA test. They can be done before the baby comes or after the baby comes.

Prenatal testing (doing a DNA test for paternity before the baby is born) is available in a format that does not put the baby at risk. However, this kind of testing is very costly if the woman uses a reputable lab. (There are some cheapie so-called "labs" that advertise heavily on the Internet, but are not worth the time, trouble and money.) The top two companies for prenatal testing are Ravgen and the DDC. The woman can go this route if:
-  she has the money or can get it, and
-  she is willing to test with both potential fathers. (One man's positive result will back up the other man's negative result, giving peace of mind.) It is possible to test with one man only, of course. It is just very common for a woman to get a negative for one man and be so frightened that it is wrong that she won't believe the test.

Neither Ravgen nor the DDC's tests are invasive nor harm the baby. They use a blood draw from the mother (her arm) and cheek swabs or blood from the potential fathers.


After the baby is born, doing DNA testing is much easier and much cheaper. The woman should use a legitimate lab recommended by the family courts in her area of jurisdiction, and as mentioned before, should test with both guys. It is a good idea for her to go with them when they do their swab, to affirm that they haven't sent a buddy in their place. Again, testing with both fathers saves the woman from doubting the results. Don't test with one guy and just assume the other guy is the dad if the first one got a negative result. .

5 - If either of the possible fathers will not willingly test before the baby comes, the woman will need legal counsel to enforce a test after the baby comes. The courts do not smile on guys trying to shirk out of taking a DNA test, since it is in the interests of society for fathers to step up to their financial duties (at the very least). So the woman will find support if she goes the enforceable legal route.


Again, if you have tricky dates or other questions, read the questions in the community and don't hesitate to post. We are a judgement-free zone and answer this kind of question all the time.

(Community Leader)
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