It's a shotgun wedding.
My parents had a shotgun wedding and had only been married a few months before I was born.
It was a shotgun wedding and they were not in love.
Toss in the fact that sperm can survive for the better part of a week inside a woman, and without protection you're looking at the possibility of a shotgun wedding, heavy flow day or not.
It's a real shotgun wedding for these two.
My friend announced her shotgun wedding this morning.