Are there many women that have taken ssri's throughout pregnancy and child birth?

Yes. There are registries for many of the different ssris. The fact that persistent pulmonary hypertension may be slightly increased to 1/500 has come under question. There is a 1.6% chance that the newborn will have increased irritability and poor feeding for 3-5 days.
Yes. Yes, and most of the time babies come out ok...Although use is not recommended but some patients need that med.