Paternity and figuring out the likely father

[Millylilly0987]

Hello. I am in a  bad mental state where I am trying to figure out who is likely the father of my child. Here is some information. I have pcos and my cycles are very irregular.

LMP August 12, 2022
Positive Home Pregnancy test Sept 22, 2022
First Ultrasound October 19, 2022 ( I was measured 9 weeks gestation but by LMP I should be 9 weeks 5 days).
So here is the dilemma. I slept with Guy A throughout the whole month of August ( possibly 16, 18, 20, 26 and 30th). I slept with Guy B on Sep 12, and about 9 days after that I got a very dark cb positive test. On my first ultrasound appointment, I came to know that I am having twins.

The 9 week ultrasound showed good heartbeat and limbs and legs can be clearly seen. I want to know how accurate is 9 week ultrasound and how distinguishable it is from 7 week ultrasound?

I am worried if it is guy B because I got a very dark positive with twins early on and what if the 9 week ultrasound is off by 2 weeks? Is the DNA test necessary in this case or I can just go with guy A as the likely father.

Thanks

[AnnieBrooke]

I can't see anything in your information that suggests the guy from September 12 was the dad. Babies in utero change a lot in a very short time -- a doctor looking at the scan can readily tell the difference between a 7th week embryo and a 9th-week fetus. Your babies began in late August, according to your ultrasound. In your 9th week there is considered to be a couple of days' margin for error when using ultrasound measurements for this purpose, but not a two-week margin for error. In your imagined scenario in which the ultrasound was "off," it would have to be by a couple of weeks, and to a doctor trained in reading ultrasound scans, fetuses just aren't embryos. If you are super nervous, you might look up information on Google about what a baby looks like in the 9th week GA and up will come things like the crown-to-rump measurement and probably some photos. But a doctor is trained to assess what is shown in the ultrasound, you're not. Sometimes you just have to trust that a trained doctor is more accurate than your worries.

For a totally different reason, you should get DNA tests with the dad and babies once they are born. This is because unless he is your husband (in which case, the law will automatically assume he is the father), you might someday need legal proof he's their father. After the babies are born, doing the tests right at the hospital is often the easiest time to get a guy to do the swabs. (Go with him to the lab, and witness.) You need to protect your kids' rights to their father's support. Check with your doctor about how to set this up.

[AnnieBrooke]

What is your due date that they gave you from the ultrasound? Or did they just give you a due date from your last period?

[AnnieBrooke]

Also, where you wrote "a very dark cb positive" I took it as meaning a positive pregnancy test. (What does cb mean?)

[Millylilly0987]

The due date they stick with is May 19, which is same based on my LMP. For cb, i meant clear blue tests.

[AnnieBrooke]

And was that the first pregnancy test you took, I assume?