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I want to know which one could be the father I'm 4 weeks pregnant?

I slept with someone on april 1st and my boyfriend on april 4th and the 5th i took a prenancy test on april 20th and its positive...who could be the father? The first guy or my boyfriend?
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134578 tn?1614729226
Hi, if the sex with both guys was unprotected, and if you assume that you ovulated around then, it could be either guy. To try to get a handle on whether you had ovulated around then: what day did your last period come? Are your cycles regular? About how many days apart are your periods?
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I track my cycles. My last cycle was on march 23,2019. My cycles just started being 29 days apart they were 26 thru 29 days every month it varied. on my ovia fertility tracker its said my fertile week is april 4th thru april 9th
Well, your fertility tracker would either be sticking with your shorter cycle or it is giving a time frame that allows for the long life of sperm in your body. Counting the first day of your period as day 1 of your cycle, if your cycles are 29 days, you would ovulate on or near day 15. If they are 26 days, you'd ovulate on or near day 12. April 1 would be day 9, and April 4 would be day 12. But you aren't out of the woods for the first guy (if the sex was unprotected) because sperm can live 5-6 days in your body. As you can see, it gives your boyfriend a slight edge but there can be no guarantees, since the two guys were so close together and probably (just barely) both in the time frame where ovulation might have happened.

You might check the post at the top of this community for the various ways to tell who is the dad -- at week 6 (counted from the first day of your last period), you could get an ultrasound, but again with the guys so close together even it might not give you a definite answer. If you try the ultrasound method, do it in your sixth week, you don't have any margin for being casual because babies begin to grow at different rates after a while. Or if you have the big bucks, do a prenatal DNA test. (Again, see the post above for more information.)
Ok so do i go by March 23 cycle which came on and was expected to come back on april 21st for this pregnancy? To determine ovualtion? O
You're better off just getting an early ultrasound (in your sixth week from your last period, i.e., beginning the count of weeks on March 23).

With your cycles recently changing length, you can't be sure if your April 21 estimate (for when the next period would have started) would have been correct.

If there was any way to know totally for sure that your next period definitely would have begun on April 21 if you hadn't gotten pregnant, you could assume that you ovulated on April 7. But you can't get a this answer by trying to count forward from the prior period.  This is because your last period does not lead into the next ovulation; your ovulation leads into the next period. (Ovulation is step 1, period is step 2, not the other way around.) There can actually be any length of time before another ovulation comes after the last period. If your cycles are shifting in length, the time between the period and the next ovulation is what's changing. This means a person can't just say "My period came on x day, so ovulation will come at x + 14 days.")

Long and short -- IF IF IF your period would have come FOR SURE on April 21, you could assume ovulation on or around April 7. And if ovulation was April 7, the guy from April 1 MIGHT be ruled out, because sperm is not expected to last quite that long in your body. (But some research suggests it can last as long as 7 days. On the other hand, most research suggests that even by day 6, it might no longer be mighty enough to penetrate the egg.) Problem is, you cannot be sure about April 7.

So, get an ultrasound in your sixth week. If your doctor won't do it, it is probably because insurance won't cover it. If so, offer to pay cash, or see if you can find another doctor who will do one. Don't get the ultrasound in your fourth or fifth week [these week counts all begin the first day of your last period] because a fourth or fifth week ultrasound is too early to see clearly. But in your sixth week or (at the latest) your seventh week, the doc can see and measure the embryo, and that crown-to-rump measurement and other developmental markers will be useful for determining a due date. Later (say, by week 12), there is the chance the baby will be growing faster or slower than average and so the doc will say "plus or minus a week." When you have to decide between two guys who were less than a week apart, plus or minus a week is not a helpful number. So do this as early after the first day of week 6 as you can. Then take the due date home and put it in a conception calculator. I am hoping it clearly indicates one guy or the other and isn't in the middle.

Again, read the post at the top of the column for more info. But the ultrasound will be your best bet right now. And write back. :)

I got an ultrasound on may 21st and it showed I was 8 weeks and 3 days I believe . They are giving me a due date of Dec. 20th. I'm now as of today 17 weeks and 4 days. Would you know now when I conceived? With my cycle coming on March 23rd 2019.
When you got the ultrasound on May 21, what due date did they give you from that ultrasound?
December 24th and it was twins in separate sacks but the one with no hearbeat measured 6 weeks she said it died the first week in may supposedly
So, to be totally clear on your story, you are saying that  May 21 was your first ultrasound, and at that ultrasound (based on the measurements of the baby) they told you December 24 was your due date? But then later your due date was changed to December 20? I would definitely use the earliest due date that you got from an ultrasound (not just from a doctor telling you "weeks pregnant" based on your last period) to try to figure this all out.
Yes may 21st I went to a pregnancy center they did an ultrasound and said I was 8 weeks 3 days which gave ne a due date of December 24th... Then I went to my actual dr  and she said my due date is December 20th after I got my ultrasound from my dr. But nothing adds up to my cycle. I'm confused on when I actually got pregnant.
Well, as I already said at the beginning, unfortunately these guys are so close together that neither is out of the running, but because of the results of your earliest ultrasound, it sounds like the first guy is more likely to be the dad. You'll need to get a DNA test to know for sure.  I'm sorry it can't be determined more precisely.
134578 tn?1614729226
I have been looking over everything to be sure of the details. One question that never got asked is if you had sex between March 23 and April 1. You began by saying you slept with one guy April 1 and your boyfriend on April 4 -- had you also been with your boyfriend before April 1?

OK, so, you said the first pregnancy center told you on May 21 that you were 8 weeks 3 days GA, and that you your due date was December 24.  There is a discrepancy because on May 21 if they were saying you were due December 24, they should have said you were around 7 weeks 6 days. (You're positive this appointment was May 21, right?) Medical places don't usually give a GA date (the "weeks pregnant" figure) that doesn't match the date you are due, unless the GA count came from your report of when your last period was, and then their ultrasound showed something different and they corrected it and gave you the due date based on the ultrasound data. In any case, once you have an ultrasound, the date to believe is the one from the ultrasound, not a date counted forward from a period.

Regarding the December 20 estimated due date that your doctor gave you after an ultrasound, how much later in the pregnancy was that? It doesn't necessarily conflict with the first due date if it was past your 12th week, because by then there is a margin for error of +/- 7 days when trying to determine a conception date by ultrasound. (Some babies grow faster than others as a pregnancy progresses.)

Unfortunately, not a lot of this points to the sex on April 4 as producing the pregnancy, though the margins are pretty slim. If you were sleeping with your boyfriend throughout, (in other words, within the week after March 23), then you're back to it being an even chance for either guy. But if you didn't begin with your boyfriend until April 4, the first guy's chances are greater.

It's too bad you didn't have your ultrasound in your 6th or 7th week; by week 12, doctors give a week's margin for error when trying to determine conception by ultrasound measurements. (By week 40 the margin for error is plus or minus three weeks!) But the info you do have does suggest that if your only options for having gotten pregnant were the sex on April 1 and April 4-5, the sex on April 1 is more likely.
Helpful - 0
Yes I had sex with my boyfriend on march 20 and yes may 21 st they said I was 8 weeks and 3 days at the pregnancy center.... They went by my cycle the first time at the pregnancy center and told me dec 28th by my cycle but by the ultrasound they did on may 21st they gave me December 24th for the due date... On june 12th the ultrasound tech  did my ultrasound and she said December 20th.  On june 12th she said i measured 12 weeks and 6 days by ultrasound.
Well, then, again, you really need a DNA test. Everything from the ultrasounds is suggesting that you got pregnant too late for the sex on March 20 to have produced the baby and too early for the sex on April 4 to have produced the baby. Since the only sex in between seems to have been the event April 1, I'm afraid your boyfriend's chances don't look great. Get that DNA test so you know what is what. I'm sorry there is no better way to tell at this point.
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