Paternity Testing with Maternal Blood Samples: Accuracy & Information

Question
I was wondering if you had any information concerning determining paternity through maternal blood samples and a swab of potential fathers.  All the sites seems to have the same information.  I want to know how accurate these tests are. The peace of mind it would offer me is truly a blessing and it is less invasive and cheaper than traditional tests like CVS and amniocentesis.  I just need to know if you have any new information or at least some further information I would appreciate it.  I just can't wait until the baby is born for fear I won't be able to bond because I will be afraid of paternity. I am also afraid it will ruin a joyous day. I also want time to prepare a home for the baby with someone who will love and provide for it.  Thank you so much for the help you have already given me.

Answer
A maternal blood sample is not going to give you any reliable information about the baby, regardless of any information you may find online.  The placenta forms a blood barrier between the mother and the fetus, keeping the bloodstreams completely separate and only allowing nutrition, chemicals, and hormones to pass.  This prevents the mother's body from rejecting the fetus's foreign genetic material and causing a miscarriage.

Your best bet is to wait until the birth, if you are not willing to accept the risks of prenatal fetal tissue sampling such as CVS or amniocentesis.