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Avatar universal

Who is my unborn Childs father?

I had sex all the time with my partner lastly on march 17th and then we split up. I then spotted for 2 days on the 26th/27th of march. I then had sex with an ex on the 2nd of April bearing in mind I have irregular periods and was not due to ovulate till the 15th April and me and my partner got back together the 13th April and had sex then. My cycles are averagely 37 days long. My scan is showing that I concieved on the 3rd April but I've been told this isn't always correct and I think the sonographer calculated it by a 28 days cycle. Please help as this is killing me.
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Avatar universal
Just to add my last period was the 26th-28th of February and we had sex on 16th and 17th of march. I would've ovulated around the 20th?? My midwife isn't convinced by the scan dates and thinks I'm closer to 14 weeks than 13 weeks. I also have a history of having small babies if that helps.
134578 tn?1578157483
OK, you are saying,


- first day of last period: February 26 (cycles approx. 37 days long)
- sex with first partner regularly until March 17
- spotting starting March 26 (two days)
- sex with second guy April 2
- sex with first guy April 13


- ultrasound tech says conception April 3
- from February 26 period, next period due around April 4 if cycles are really 37 days long; if you count the spotting on March 26 as a period, next period due May 2, and ovulation would be expected April 19 from that. (Frankly, I would throw out all the assumptions based on when your last period was, you have irregular cycles.)

So, the big question is, when did you get the ultrasound? And did the ultrasound tech say "conception" was such and such a date, or did she say you are x weeks pregnant?
And, while we are on the topic of what the ultrasound tech said, what did she say is your estimated due date?
Hi Annie, Firstly thankyou for getting back to me. I had my scan last Friday (15/6/18) and I was told baby was measuring at 12+3. I was given Xmas day as a due date. She said that means I would've concieved on the 3rd of April yet she didn't ask me what my cycle was like. I'm just really confused and it's giving me awful anxiety.
Sorry, Just to clarify does that mean the baby is definitely my partner's?
Also just to add I first seen my midwife on the 15th of may and she felt my stomach and said I'm closer to 11 weeks at that time as she could feel something there, something she said she wouldn't be able to feel if not as far gone. My doctor also said the same.
134578 tn?1578157483
Well, sweetheart, I see what you want, but even adding a week to the ultrasound estimation of when conception was is not going to make your boyfriend the father. You broke up on March 17, right? The good news for you is that because your ultrasound was in your 12th week, it's possible for you to be a week further along than the ultrasound suggests, due to variations in the growth rates of embryos. (When using an ultrasound to try to determine conception, at 12 weeks GA doctors usually will say there is a margin for error of +/- 7 days.) Some babies grow faster and some grow more slowly than the average growth curve on which ultrasounds are based. (By the time a woman is in her 40th week, an ultrasound can be up to three weeks off if used for trying to determine when she got pregnant. But not in week 12.) This means that you have a possible conception range of from 7 days earlier through 7 days later than April 3.

Unfortunately for hoping your boyfriend is the dad, you and your boyfriend's last sex before the breakup was March 17. Even if you move your conception date back the week suggested by your midwife from the April 3 estimated conception date given by the ultrasound that measured the baby, that only takes you back to March 27. And even adding a further margin for the 4-6 day life of sperm in the woman's body still only takes you to March 21 or so.  It takes some wishful thinking not supported by medical science to stretch this even back to March 17.

One thing you can do is see what the next ultrasound indicates about whether the baby is growing faster than the average or not. If it also points to December 25 as the due date, that would suggest your baby is not growing faster or more slowly than average.  If your baby is not growing faster than average, then the idea that you are really a week further along than you think is probably incorrect, no matter what the midwife could feel with her hand. And if your baby is continuing to match the averages and the conception date keeps coming up as April 3, you would have to be ready to hear that the other guy is the dad. But if your next ultrasound gives you a different due date than Christmas, it might mean the baby is growing at a different rate than average, and then you could hope the first ultrasound was also affected by the baby's rate of growth being off the average. You would have to extrapolate which direction (whether the baby is growing faster or slower than average) by what due date you get.

If you absolutely need to know for sure before the baby comes, Ravgen and the DDC do accurate prenatal DNA tests (non invasive), at a cost. If you go this route, don't go to a cheapie so-called lab advertising on the Internet, go to only one of the two I just mentioned. And in any case (DNA testing now or DNA testing after the baby comes), be sure to witness the guys doing their tests and be sure to test with both guys. That is the best way to know, since one guy will get a yes and the other guy will get a no.
Hi, according to my period checker I would've ovulated on the 20th of March. Is that still possible? My ex says he can't have kids. He's epileptic and his medication has affected his fertility. He's abit of a dog and has slept with hundreds of women, doesn't have kids and had never got a woman pregnant.
Guys who want to have unprotected sex always say they can't have kids. Epilepsy meds can have a negative effect on sperm count, but there is no literature that says they take the count down to 0. It might take the count from millions of sperm in one ejaculation to hundreds of thousands of sperm in one ejaculation, or even to tens of thousands in one ejaculation. But that is still enough. It only takes one.
134578 tn?1578157483
A period tracker app is an automated calendar that intakes data from prior cycles and makes guesses. If your cycles are not regular, anything can happen the following month, and the tracker is pretty much just guesses. If the ultrasound, which saw and measured your actual baby, says you got pregnant April 3, it is pretty hard to turn that into March 20 just on the basis of a period tracker.
The baby wouldn't keep still either making it difficult for the sonographer to get measurements. It was like a little human pinball pinging all over the place. My partner thinks it's his and doesn't know about the other guy. I just feel crushed.
134578 tn?1578157483
Can you afford the big price of a prenatal test? At least you would know early. Ravgen can even do a 'discreet' test, using a swab from the guy's drinking glass or glass of wine. You could test with both guys that way without telling your partner, and would only have to tell him bad news if there really was bad news.
That's not possible at the moment as he's working away and I don't see or speak to my ex. My partner slept with a woman the middle of march (on a weekend) a couple of years ago and she was told she concieved on the 1st of April when he wasn't even in our town at the time. He slept with her 2 weekends prior to that and she was given a due date of the 9th of Jan 2017. I was convinced by dates that he wasn't the dad yet a DNA test showed he was although it was a cheap £69 one off the internet. She had a little boy on the 21st of January 2017. All of this pregnancy malarkey doesn't make sense.
Well, just because someone does a cheapo test on the Internet that is subject to fraud and mistakes, does not make "this pregnancy malarkey not make sense," you guys just did a crap test that was possibly tampered with or handled in a mistaken way and the lab might not have even processed it. A woman on here once wrote that she had faked the results letter of a DNA test a guy had her take. There is a lot of chance for human fakery or error when you do things on the cheap.
(Incidentally, the part about her being told she conceived on April 1 can't be correct if she was given a due date of January 9. Projected ovulation date for January 9 is April 18. It sounds like the "cheap £69 test off the internet" was not even worth £69.)
That was my arguement about it the whole time. He was with me the whole of April and didn't leave my side unless he went to work. Also the child looks nothing like him. I know deep down it's not his baby.
So, you see, never just order a test on the Internet. Only do tests from gold-standard labs (and there are very few of those in a field littered with fakes).

Please take seriously the need for your boyfriend to talk to a lawyer to see what his liability might be if the girl keeps claiming he is the father. This kind of thing can have a long time effect.

And if you do prenatal testing, please only use the top labs. I know it is more money, but you want to be sure.
134578 tn?1578157483
OK, believe it or don't. But what else do you have? Sitting in fear for the rest of your pregnancy and not believing anything your doctor or midwife says? You should at least be making some plans about what you are going to do when the baby is born. (Hint: It cannot be hiding the fact that there is a question. That would be immoral to all concerned, and the truth will someday come out anyway. People take DNA tests for fun to learn their heritage. How would your child feel to get this news at age 20, and you never told him or her?)

Anyway, the parts where your story cannot be answered for certain due to the limits of research are:

- How long does sperm last in the woman's body for sure? Much research says 4-5 days. Some says up to 6 days. Some says it can even last longer, but that sperm is not strong enough to penetrate the egg after about day 5 or 6. But there is no DEFINITIVE research that says "absolutely." (And how could there be, there is certain to be variation among men.) So, maybe you can say to yourself that his sperm is of the longer-lasting kind.

- The part about the margin for error when there is a fast-growing baby. Doctors say +/- 7 days at 12 weeks, and +/- 3 weeks at 40 weeks. But how well has this been tested? Do we KNOW it might not be +/- 10 days at 12 weeks? Because all you need is about 3 or 4 more days and your boyfriend is back in the mix. Especially if he has long-lasting sperm.

Regarding that Internet DNA test, did your boyfriend send in the swab himself? (Internet tests can readily be done fraudulently, if a woman wants to substitute swabs or even falsify the report.) If your boyfriend has a possible child out there, he should seriously insist on a DNA test done at an official lab (not a cheapie one done by mail) and the sooner the better. Because she could come back to him for a LOT of back child support sometime. I have heard horror stories of guys getting hit years after a child is born for child support for every month the child was alive.  He should know for sure now, and should do this with the help of a lawyer, and should go to a lab certified by the family courts for legal determination of paternity.

One other possibility that might help you sort this out is if the baby is a girl. If your next ultrasound shows this, write me back. It would be a point for your boyfriend.

Finally, you need to decide what you are going to do if you wait and just do a DNA test when the baby comes, and the wrong guy is the dad. I would put the screws to the ex for child support, myself, especially if he is just a cad. But if you don't want him in your life at all, I think you can also write off his obligation to child support in exchange for him never wanting a relationship with the child. You should see a lawyer and a counselor also, to be prepared to think over what you want, if that unpleasant possibility becomes a true fact.

I sent my scan pics to the nub experts on Facebook and most of them said they think it's a girl due to no visible nub. I'm not interested in child support. Never had a penny off my 2 boys dad. I work full time and do it all myself. The mother of the boy doesn't let him have anything to do with him on the basis because he doesn't want her, she's only young and immature and doesn't understand she was a mistake, a one night stand. He swabbed himself and posted it but the report went to her via email. I understand what you are saying about the margin of error as my youngest son showed me 2 weeks ahead at his 12 week scan even though I was on the implant at the time. He was born at 28 weeks weighing 3lb 1oz so quite a good weight. My eldest measured ahead too and he was premature at 31 weeks so as you can see I don't have the most straightforward of pregnancies lol
134578 tn?1578157483
You getting a DNA test is to determine for sure who the dad is, hoping your boyfriend is the dad but bracing in case he is not.

The topic of a DNA test regarding this gal who got pregnant with your boyfriend from a one-night stand, is about something different. It's about him not getting blindsided some day by a demand for a big payment of back child support for that child. Just because the mother of the boy does not let the child have a connection to him at this time does not remove the risk of a later demand for child support and for back child support (depending on the jurisdiction). Until the child is 18, if the law thinks your boyfriend is the father, he could be on the hook. Getting a DNA test that is legally admissible is the sensible thing for him to do, the sooner the better. Even if she refused his child-support money, if your boyfriend lives in a place where he would be obligated to pay it, he would be smart to be saving it up, month by month, in an account that he doesn't touch. Then if it is demanded (for example, if she goes broke, or a more far-fetched example, she dies and his relatives call your boyfriend for support), and if the child proves to be from your boyfriend on an official DNA test, your boyfriend will have the money. In some places it really can be very high, all the back child support that was not paid. (If the child reaches 18 or 21 and there has been no demand for the money, you two can go on a cruise on the proceeds.) Tell your boyfriend to talk this all over with an attorney. It's important.
Ok. Thankyou for speaking with me and for your help in this matter.
Sorry, one last thing. In your opinion what would you say the percentage is?
To be the dad of your child, your boyfriend would have to have long, long lasting sperm, or the ultrasound would have to be off bt more than a week, or a junction of those two things such as he has rather long-lasting sperm and the ultrasound is off by a week.  The ultrasound being off by a week is not impossible because it was in your twelfth week. (The next ultrasound will give you a clue if it suggests a different due date. If so, it suggests a baby growing at a different rate than average and that puts the first ultrasound into question.) I'd say his odds are slim but not impossible, but more data will come that will help figure it out. Write back when you learn the baby's gender.
His first child is a girl if that helps but I've got in touch with my ex who has agreed to do a pre-natal paternity test now.  Just waiting on it to arrive.  For his second child to be a boy and him having intercourse with the mother 2 weeks prior may suggest long lasting sperm? Either way I need to know for sure as you're right. This will affect everybody concerned.
The spotting I had in march was 25th/26th I got my dates wrong
I don't think any information you have about the other woman and her baby is reliable enough for you to say "for his second child to be a boy and him having intercourse with the mother two weeks prior ..." as though this was the Revealed Word. Anything could have gotten tangled up in that story, and he did use a cheap and unreliable test. The problem with tests like that is that they provide justifications -- either a guy can claim he is not the dad when he might actually be the dad, or the woman can claim the guy is the dad when the test was so poor that who knows if that was even the case. Only go with the top two labs if you are doing DNA testing. It's too important for it to be done wrong.
134578 tn?1578157483
Hi, you said "Just waiting for it to arrive." Don't use an at-home prenatal paternity test, no matter how cheap it was. They are not reliable. Do a test with Ravgen or the DDC only.
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