+1 x 1000 for the first sentence of this quote. However, as a fetus in utero, we receive passive immunity from our parents in the form of IgG antibodies that pass through the placental tissue, from maternal blood to the fetus. Babies do not begin to develop their own adaptive immune responses until post birth.
I've said this before, but coming from a practicing molecular toxicologist, there are no causative elements of owning a snake that will induce any sort of teratogenesis or birth defects in a developing neonate. Yes there is a small risk of salmonella from handling reptile feces, but studies have shown that a multitude of other sources pose a much higher risk of conferring pathogenesis other than snakes. Everyday humans are bombarded by environmental toxins and microorganisms in the air, water and food that we consume. Luckily, millions of years of evolution has equipped our physiology with multiple and redundant mechanisms for neutralization and metabolism of toxicants, as well as immunity to pathogenic material.
Obviously a pregnant woman should be shielded from any obvious exposures like alcohol, cigarette smoke etc. But there is nothing about handling a reptile that will cause any sort of issue if general hygiene standards are observe.
To the OP: Keep your reptiles clean and you wont have any issues. Congrats on the new baby, and good luck!