Thanks for writing to us with your health concern.
It is just not possible to determine who is the father without a paternity test.
This is because the two encounters are two closely placed.
they are just 2 days apart in fact, even early trimester scans have an inherent error margin of upto 5 - 7 days.
So clinically speaking, you NEED to have a paternity test to establish who is the father.
Blood samples taken from the mother, baby and the man thought to be the baby's biological father can then be tested for DNA fingerprinting and in a large proportion of cases can prove whether the man in question is definitely the father.
It is technically possible for a blood sample to be taken from a baby whilst it is still in the womb.
This can be done by amniocentesis
or CVS .
However, lately, paternity testing can be done by collecting mother's blood sample too, anytime after 8 weeks, and is upto 99 % reliable.
Please consult your obstetrician and go for Paternity testing as it is a vital question for your life.
All the best
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