worried

[ashk1130]

If my lmp was the first week of December and my due date is Sept 14th when did I get pregnant

[AnnieBrooke]

Well, get the guy from the 16th some official material from a medical site like Mayo Clinic's or even the National Institutes of Health, on how long sperm can last in a woman's system.  Then copy off some material from a site like the American Pregnancy Association (sorry, think that's the name) about the accuracy of ultrasounds as time goes by in the pregnancy.  Write a calendar with an X on the 16th and a circle that stretches to the 21st or 22nd, and then put a circle of a different color to point out the margin for error on an ultrasound-based date that was given to you in your 12th week.  He should be able to see that they overlap.  

Good luck.  Can't guarantee anything )odder things have happened) but it does sound like Mr. 16 is more likely the dad than Mr. 10.

[ashk1130]

Nope just tenth then six tenth

[AnnieBrooke]

Well, not quite.  If the sperm from the sex on the 16th lasted the usual length of time in your reproductive system, it was there and viable until at least the 21st, if not longer.  And that is not even taking into account that an ultrasound can be off by a few days by the time you're at 12 weeks.  Sperm lives in the woman's reproductive tract for up to 5 or 6 days in optimum conditions.

(In fact, that is why you can't even be certain the guy on the 10th is ruled out.  The long life of sperm in your system takes you out to the same day you had sex with the second guy.  All that would have to happen is for your ultrasound to be off five or six days, and even he is still in range.)  But the evidence is less strong for the guy on the 10th.

I assume, in all of this, that there is no other sex on the 19th, or the 21st, or something like that.  We are only dealing with one guy on the 10th and another on the 16th, and then nobody after that for at least a week or two?

[ashk1130]

Ya he said he been doin the research and the only where he can be the father if its a week off

[AnnieBrooke]

Maybe he doesn't know that a 12th-week ultrasound can be off by a few days.

[ashk1130]

I know I'm scared my boyfriend the one on the tenth said he leaving if it ain't his and stop dealing with Guy on sixteenth. Guy on sixteenth keep saying the dates ain't adding up why he keep saying that

[AnnieBrooke]

*week* not weed lol

[AnnieBrooke]

I would guess (even with the lack of precision of an ultrasound in your 12th weed) that it is likely you got pregnant from the event on the 16th.  You definitely need a DNA test once the baby is born just to rule out the unlikely, however.

[ashk1130]

Irregular and yes both unprotected

[AnnieBrooke]

Are your periods usually really regular, or are they somewhat irregular?

Anyway, the material I've seen says that 12th-week ultrasounds can be a few days off.  But it does not sound like any of this will make your dates stretch as far back as the guy on the 10th (though there is a ghost of a chance that if the first guy's sperm lasted five days).  Were both sexual events unprotected?

[ashk1130]

My period started around the first of December

[ashk1130]

The first on the tenth and second on the sixteenth

[AnnieBrooke]

How close together were the sexual activities that you are concerned about?

[AnnieBrooke]

12 weeks is usually considered early enough to get a relatively close estimate on dating, perhaps a few days off.

[ashk1130]

At twelve.weeks

[ashk1130]

At twelve.weeks

[AnnieBrooke]

Here is what the conception calculator says:

Assumed first day of last menstrual period:  December 8
Probable date of ovulation:  December 22
Possible dates of conception:  December 18 to 26

Due date:  September 14 (40 weeks)

This will only be accurate if you got your due date from an ultrasound that was early in the pregnancy.  If you got your ultrasound later on, it might be off by as much as two weeks.  When did you get the ultrasound?