Who is the father of my baby?

[Mvk12345]

Need help as I am freaking out more and more about this. I'm currently 37 weeks pregnant and not sure who the baby's father is.  

The relevant dates are:

June 1st: LMP started. My cycles are usually 28-34 days.

Night between June 11th and 12th: sex with guy no. 1.
June 13th: sex with guy no. 2 (late night). Took an ovulation test, negative.
June 14th: the line of the ovulation test was stronger but still negative.
June 15th: had sex with guy no. 2 (late night). Ovulation test was positive (took the test at 2pm).
June 16th: ovulation test was negative.
June 24th: took a pregnancy test, negative.
June 25th, early morning: super fainted second line on pregnancy test. Increasing every day since then.

I've had 3 scans. First one estimated I conceived June 17th (I was 7 weeks + 1 day at that time) second scan at 13 weeks estimated I conceived June 16th. Third scan at 18 weeks also estimated I conceived June 16th.  

I know the dates are close and that only a DNA test would tell for sure. But what are the odds the first guy is the father?
Guy no. 1 ejaculates every single day while guy no 2 only did on those two dates during that time. Guy no. 2 has also gotten me pregnant before.

[AnnieBrooke]

You ask "Does it mean 95% of guy 1's sperm would have been dead by the time I ovulated?" The fast answer is no, but it's really that the question is based on some false notions.

A man ejaculates between 2 and 5 mililiters of semen (on average, about a teaspoon) in one ejaculation. Each ml normally contains about 100 million sperm. This means, one ejaculation puts 200 million to 500 million sperm in your body (and it only takes 1). Even if there were only 5% left, that still would leave 10 to 50 million sperm in your reproductive tract from him. The idea that "most of the sperm would be dead" doesn't help when the remainder is still in the millions.

Also, research is not conclusive about how long sperm stays viable in the woman's reproductive tract. I've seen research papers that give a range of 3-5 days, 4-6 days, and even one that said longer than 7 days (though its ability to penetrate the egg at the 7th day was questioned). So the idea that 95% would be dead based on a five-day time span is not really going to be factual.

Also, you don't know for sure when you ovulated. One doc said the 17th, one said the 16th? but somewhere along the line you were given a due date that (by the conception calculator I use) suggests the 15th.

So, I would take issue with the assumption that 95% of the sperm would be dead, the idea that even if so, 5% of the sperm is somehow not enough to do anything, and the idea that ovulation has been accurately pinpointed to a certain date. The part I do agree with is that the second guy probably put more sperm into you than the first guy, and seems to be a little closer to the date of ovulation. But the first guy is still in range. Is the baby a boy or a girl?

[AnnieBrooke]

I asked about boy or girl because if you look up the Shettles method of determining gender, there is the theory (not proven) that the further the sex is from ovulation the more likely you are to have a girl. If the baby is a boy, Shettles theory doesn't rule either guy out because you don't have proof of when you ovulated, but maybe if it's a girl there might be a slightly increased possibility that the earlier sex produced the baby.

Is the guy from the 15th your husband? If not, I assume you'll be getting a DNA test with him just so the baby has legal proof of paternity, (with no particular mention of wanting to rule out any other guy as father). Please consider testing with the other guy, too. (Even if you never mention this to the second guy.) This way, one guy's test result confirms the other guy's, and you will never have to wonder if the test was accurate.

[Mvk12345]

Hi again and thank you for your response. First, to answer your questions:
I don't know whether the baby is a boy or girl. I've read a lot about the Shettles method so I get why you're asking.
And for the due date: my first ultrasound was on July 23 and baby measured 7+1 day. I told the the doctor it was important for me to get it right so he measured very carefully, twice. That gave me the due date march 9 and a conception day of June 17. (I live i Europe and here pregnancies are considered full term at 39+6 and not 40+0, maybe that's why we get different dates?)

After a positive ovulation test I'm supposed to ovulate within 12-36 hours. I had one on June 15t at 2 pm which indicates I ovulated June 16 or possibly June 17. I had my first positive pregnancy test on June 25, early morning. I think that also indicates I conceived on June 16, because when I got pregnant with my son who is now two years old, I also had my first positive pregnancy test 9 days after intercourse (and that was the only time I had intercourse that month so I know I couldn't have gotten pregnant sooner).

As you can see, I've spent a lot of time analyzing this (I'm very thankful I paid so much attention to dates and ovulation that month!)
I've been reading everything there is to know about the subject all my pregnancy and of course come to the conclusion that I can't rule guy 1 out without a DNA test, although I do believe that guy 2 had better odds (what I'm thinking here is that if it's true that only about 5% of the sperm would be alive after 4 days (let's just say it is), and let's say that statistically 80% of the sperm from intercourse on the day before would be alive, the second guy does have better odds, regardless of whether we are talking about hundreds, thousands or millions of sperm. Does that make sense?

I so wish there was some data about what sperm has the best odds to fertilize the egg (when talking about "old" and "new" sperm), but I'm guessing it isn't since it's not that common to have intercourse with two different men only days apart and therefore hard to tell which sperm from which intercourse actually fertilized the egg :)

I can see that most people don't update after they had the paternity confirmed, but you seem very experienced on this - do you have any insight in who turned out to be the dad in situations similar to mine? (Sex with two men, couple of days apart, both intercourses occuring before ovulation). If so, that would be interesting to hear!

Thanks again for your time :)

[AnnieBrooke]

Though it sounds precise, "5%" is not a useful number because it's based on too many presumptions. Your assumption is that a batch of sperm would tick down in viability over time. But for all we know, all of the 100-500 million sperm that started out together remain at 100% viability until on a certain day they all die together. And since even if the 5% figure had validity, the "odds" don't matter much if there are still 10 to 50 million sperm, I'd stop looking for an answer based on one guy's sperm theoretically being fewer in your body when you ovulated.

Regarding the thought that it would be significant if the sperm is "old" or "new," the counterbalance would be that the first guy's sperm was right there waiting when ovulation occurred, and the second guy's sperm still had to swim up the tubes to meet the egg.

I do agree that the first guy seems a little further from the date of ovulation, which is why I mentioned the Shettles theory. Unfortunately, all of this is too close together to rule out anything, but in your shoes if I were to find out the baby is a girl, I would take more comfort from that than the "5%" theory or the "old-versus-new" theory.

Why don't you just do a prenatal DNA test with the first guy? Is it too close to the time the baby is coming to seem worth the money? If you're "freaking out more and more," maybe it would be worth it.

[Mvk12345]

Hi, to answer your last question, I haven't done a prenatal DNA test simply because I couldn't find anyone who would get my blood drawn for that purpose. I'm due in 7 days so will find out soon enough...

[AnnieBrooke]

I assume you can do a DNA test at the hospital when the baby comes? Are you concerned about asking the second guy to do one?

[Mvk12345]

I won't be able to do a DNA test at the hospital (In my country the municipality is responsible for determining paternity and they will also do a DNA test if I ask for it). I think I will be able to tell who's baby it is though when it comes, since me and guy 2 are scandinavian and guy 1 is from the middle east

[AnnieBrooke]

I'm thinking about the legal financial responsibility for the baby; 'child support' payments. If you aren't married, would a DNA test be required before the law would require the father to help support the baby financially?

[Mvk12345]

Just came back to update for any future reader :). Baby (a girl) is here and there's no doubt guy number 2 is the father. I might do a DNA test just to be completely sure but there's no reason really.

[AnnieBrooke]

It sounds like the Shettles method came through for you. :-)  I found the 5%/95% theory problematic, but if you had known the baby was a girl, I would have certainly have voted that the second guy was the father. Congratulations!

Do a DNA test only if you need it to affirm the baby's legal rights to the father. (In the U.S., if a couple is not married, a DNA test is required when legally determining paternity. Also, of course, if a guy is to be asked to help support a child financially for the next many years, he might well want proof the baby is from him.) If you have no complications there (such as, if you are married to guy number 2) then in your shoes I'd put the whole question behind me and just go on with life.

[AnnieBrooke]

Unfortunately for trying to estimate the odds that the first guy is the dad, from what you're saying, viable sperm could have been in your body from both guys when you ovulated. Then it's just a matter of which among the millions of sperm made it to the egg before all the others. It only takes one sperm.

The first guy ejaculating every day, if he never misses a day, could reduce his sperm count. But this can't be sure to make his chances 0%. He probably has lower odds, but not "no chance."

Do both guys know that there is a question and have they both agreed to do a DNA test?

[Mvk12345]

Thank you so much for your reply. I already know guy 1 can't be ruled out as the sex was too close to ovulation. I remember reading somewhere that sperm has a 5% chance of surviving more than five days, does that mean 95% of guy no 1's sperm would have been dead by the time I ovulated? And there would be a higher amount of sperm from guy no 2 in my body?

Guy no 1 knows I'm pregnant and that there is a possibility it could be his, guy no. 2 thinks it's his. Having sex with guy no. 1 was something I was basically forced into which makes everything so much harder. I feel like I can't even suck it up and blame myself for it because it was never something I wanted to do.

[AnnieBrooke]

What was the date of the first scan, that said you were 7 weeks 1 day? And what estimated due date did they give you from that scan?

[Mvk12345]

The date of the first scan was July 23 and it said I was 7 weeks 1 day. Estimated due date from that was March 9. On the other two scans they changed my due date to March 8.