Pregnant Girl Births Swamp Creature

by Rizzo
(Watervliet, New York, USA)

I have been trying to find the name of this 70's or 80's movie for a while now. Maybe someone here can help me out.

There's a little town preparing for some kind of festival or celebration when these swamp-like creatures begin attacking.

A pregnant girl gets attacked and clawed by one of the creatures, but survives.

In the end, we see her in the hospital about to give birth, but instead of a human child the baby is one of the creatures.

If anyone can help me with this I would be greatly appreciative since as I said this has been bugging me for a long time. Thanks.

Also it's not Humanoides from the Deep.