Inserting an escape from a normal, natural birth by passing out of the womb without being born does not make sense.
Look Ma; no Blood!
No mess!!
No "My water's broke!!!"
The amniotic fluid is there in the amniotic sac due to the new life bringing in the fluid from the connection between the uterus/womb and the placental implantation connection.
Again, the placenta is made by the growing child not the mother. The fluid in the amniotic sac is there by the actions of the growing child process. So, both the amniotic fluid (the 'water' with effluent content) and the bloody discharge would require the offerings. The implantation pregnancy in the uterus OPENS the womb.
The cervix is an os, a portal. Jesus was not brought into Mary's uterus via this portal and it is just as likely that He did not exit her body via this portal. The offerings indicate the water and the blood exited the portal (requiring the offerings), but to assume this means the BIRTH of Jesus came through that same portal is not a necessary conclusion. Just like it is not necessary that Jesus leave the rock tomb by the portal obstructed by the large stone.