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is ultrasound accurate for determining conception date (paternity)
Hi I gotta be really honest and straightforward. I was shocked when i found out that i was pregnant. I didnt know what to do. And this was actually the real problem. I slept with two guys. I wasnt proud of course. I had sex with the first guy a week after my last menstrual period, which is another problem because i have irregular period. And then i saw he did the withdrawal method. He withdrawed his thing 3 secs before his ***. Then a week after, i had sex with another guy. Later in 3 months i found out i was pregnant. I was really shocked. Because whenever i have sex with guy number 2 on those days it was always seems to be his doing the withdrawal method as well. But then when i asked him he told me that the put his *** on me because i said i just had my period. Now the problem was, when we did an ultrasound the baby was a week older than we expected. It was supposed to be 9 weeks but it was written that it was 10 weeks and 2 days. We were confused about it and i told him about the other guy. So i want to ask the opinion of the people out there that is it possible that the first guy was the father of my child?
COMMUNITY LEADER
Honey, unfortunately pulling out is such a bad method of birth control that it is not even considered birth control. If it has been successful for you in the past, you've been fortunate. You could have been lucky again this time. But saying he came three seconds after pulling out does not fill me with confidence that this time it would be the luckiest of times.
Due to the margin for error on your ultrasound and also due to the dates of the sex being only 4 days apart, it's just not possible to split the difference between March 5 and March 9. You can get a prenatal blood test for paternity for an (unfortunately very large) fee, I don't usually recommend it because most of the women who write in are saving every dollar for the baby, and they don't even know if they can afford a regular DNA test (*after* the baby comes), which is a tenth the cost. But it is worth knowing that prenatal DNA testing for paternity can be done from a blood draw from the mom and a swab from the potential dad(s). If you go that route, use only Ravgen or the DDC, don't consider any of the charlatan outfits that offer cheapie tests on the Internet. But other than a DNA test, I'm afraid there is no clear answer with your dates this close together. The sperm from the first guy, if you had any, would have been alive in your system still when you had sex with the second guy.
Due to the margin for error on your ultrasound and also due to the dates of the sex being only 4 days apart, it's just not possible to split the difference between March 5 and March 9. You can get a prenatal blood test for paternity for an (unfortunately very large) fee, I don't usually recommend it because most of the women who write in are saving every dollar for the baby, and they don't even know if they can afford a regular DNA test (*after* the baby comes), which is a tenth the cost. But it is worth knowing that prenatal DNA testing for paternity can be done from a blood draw from the mom and a swab from the potential dad(s). If you go that route, use only Ravgen or the DDC, don't consider any of the charlatan outfits that offer cheapie tests on the Internet. But other than a DNA test, I'm afraid there is no clear answer with your dates this close together. The sperm from the first guy, if you had any, would have been alive in your system still when you had sex with the second guy.
Thats really sad. But is guy 1's withdrawal method doesnt count? Does it not make him a much more unlikely to be a father? Im sorry i dont mean to be tacky. I just want a more certain answer coz im getting frustrated. And also, i just had my period a week after. And guy1 and i have been doing this for so long and frequent and not getting pregnant. Its just this guy2 that came along and admitted he did it when i get pregnant. Dont get me wrong i actually want guy1 to be the dad. Thanks.
COMMUNITY LEADER
If your first ultrasound was the one that gave you the due date of December 1, it would label March 10 your conception date, but not if the ultrasound was in your tenth week. It would be March 10 plus or minus about 4 days either direction. This means sperm from the sex on March 5 is in play, and sperm from the sex March 9 is in play. So, either guy could be the dad. If the baby is a girl, it suggests slower-swimming, longer-lived sperm. But that could still be either guy given the margin for error.
So, either guy. Not a higher chance to either guy, maybe 51% to 49% but no way to know.
So, either guy. Not a higher chance to either guy, maybe 51% to 49% but no way to know.
He said, he c u m m e d on me through the dates march 9 to 15. Either from those dates between.
COMMUNITY LEADER
Does "But he's certain he did it on second week of March mean what, March 7? It really does matter, if you were given a due date of December 1 when you had your earliest ultrasound.
Thanks annie. Yes they changed it from dec. 1 they made it to dec. 4. I dont know if that makes a difference though.
Anyway, the utrasonologist said it was a girl. But she had a hard time determining it though. Took us 30 mins. Or more because my baby doesnt spread its legs. I think my sonologist just said it so for the sake of having value of my money rather than saying it was inconclusive. But later she said there are times that the gender changes.
Guy 2 said he did it on that day. March 14. But he's certain he did it on second week of march.
Anyway, the utrasonologist said it was a girl. But she had a hard time determining it though. Took us 30 mins. Or more because my baby doesnt spread its legs. I think my sonologist just said it so for the sake of having value of my money rather than saying it was inconclusive. But later she said there are times that the gender changes.
Guy 2 said he did it on that day. March 14. But he's certain he did it on second week of march.
COMMUNITY LEADER
I get guy #2 as the dad, but not by a wide enough margin that you could ignore the need for a DNA test. Can you be more specific than saying it was "probably" March 14 when you began to have sex with him?
There are three factors that affect each other here.
1. A medical count of pregnancy does not begin when you conceived.
When a doctor or ultrasound tech uses a count in weeks for the pregnancy, he or she is NOT beginning the count when you conceived, but is instead saying that the average woman, as far along as you are, would have had the first day of her last period on the day the doctor used to begin the count. The first day of bleeding (or the computed first day of bleeding, if the woman's cycles are irregular) begins the medical count of the weeks of pregnancy. Not the day of conception. Therefore, May 9, the doctor was saying you were 8 weeks 2 days from conception, and 10 weeks 2 days from the (calculated from averages) first day of your last period. That brings the estimated conception date to March 13.
2. There is a margin for error when using ultrasounds to date pregnancies, and it gets bigger as the pregnancy goes along.
10w2d is pretty late in pregnancy for someone to be able to use an ultrasound to pinpoint when it began. The margin for error at 6 weeks is +/- 1 day, because all embryos begin as one cell and then divide into two and then four. But due to differences in embryonic growth rates, by 12 weeks the margin for error in using an ultrasound for dating is +/- 1 week. Your ultrasound was much closer to the 12th week than the sixth week. This helps if you want to include the guy on March 14, since March 13 is pretty close. But it also opens the door to the guy on March 5.
3. Sperm can live a while in your system.
Research says sperm lives in the woman's reproductive tract anywhere from 4 to 6 days (depends on the research). Some research says sperm can live even longer, but other studies have suggested it is not very strong by the 6th day and might not be able to penetrate the egg. If you add the long life of sperm in the woman's body to the margin for error from the ultrasound in your tenth week, the guy from March 5 could come back into the picture.
____
One thing that might make some of this more clear is if your due date has been changed during pregnancy as your pregnancy has moved along. Another is the gender of the baby, is it a boy?
There are three factors that affect each other here.
1. A medical count of pregnancy does not begin when you conceived.
When a doctor or ultrasound tech uses a count in weeks for the pregnancy, he or she is NOT beginning the count when you conceived, but is instead saying that the average woman, as far along as you are, would have had the first day of her last period on the day the doctor used to begin the count. The first day of bleeding (or the computed first day of bleeding, if the woman's cycles are irregular) begins the medical count of the weeks of pregnancy. Not the day of conception. Therefore, May 9, the doctor was saying you were 8 weeks 2 days from conception, and 10 weeks 2 days from the (calculated from averages) first day of your last period. That brings the estimated conception date to March 13.
2. There is a margin for error when using ultrasounds to date pregnancies, and it gets bigger as the pregnancy goes along.
10w2d is pretty late in pregnancy for someone to be able to use an ultrasound to pinpoint when it began. The margin for error at 6 weeks is +/- 1 day, because all embryos begin as one cell and then divide into two and then four. But due to differences in embryonic growth rates, by 12 weeks the margin for error in using an ultrasound for dating is +/- 1 week. Your ultrasound was much closer to the 12th week than the sixth week. This helps if you want to include the guy on March 14, since March 13 is pretty close. But it also opens the door to the guy on March 5.
3. Sperm can live a while in your system.
Research says sperm lives in the woman's reproductive tract anywhere from 4 to 6 days (depends on the research). Some research says sperm can live even longer, but other studies have suggested it is not very strong by the 6th day and might not be able to penetrate the egg. If you add the long life of sperm in the woman's body to the margin for error from the ultrasound in your tenth week, the guy from March 5 could come back into the picture.
____
One thing that might make some of this more clear is if your due date has been changed during pregnancy as your pregnancy has moved along. Another is the gender of the baby, is it a boy?
I had sex with guy 1 march 5. Guy 2 on probably march 14 onwards. Thats the time he said he put it in me. Yes the g.a is 10wks 2 days
COMMUNITY LEADER
If you have a copy of the ultrasound report, could you look at it and say what date (calendar date) it was, and if the 10 weeks 2 days is labeled "GA" or gestational age?
Also, do you have a calendar date for the sex one week after your period, and then a calendar date for the sex one week later with the other guy?
Also, do you have a calendar date for the sex one week after your period, and then a calendar date for the sex one week later with the other guy?
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