Suggestive congratulations -wtf?

AKMama • I'm a Mama Bear w/3 very active Cubs + 1 on the way. Our home is never as clean as I'd like, but it's filled w/love!
Just needed to get this off my chest:
What is with the suggestive congratulations or the innuendos in response to announcing a pregnancy?  What compels a person to feel that it's okay to make reference to your sexual relationship when a simple "Congratulations" will suffice?
My ex-husband's wife just congratulated my husband yesterday by saying "way to go, Mark!" With a eyebrow raise and a lewd nudge-nudge. Ew. We get along okay but not THAT well.
What about you ladies?