A student recently wrote me and shared some exciting news that included an implicit translation question:
[…] my wife and I are expecting our first child! (An bɛ ka dɛn sɔrɔ?)
For reference for others, here’s my response:
To say something close to “we are expecting”, I wouldn’t say “An bɛ ka den sɔrɔ”, but rather something something more like “N muso kɔnɔma don” [My wife is pregnant] or “Kɔnɔ bɛ n muso la” [Pregnancy is upon my wife]. You could also say “An bɛna den sɔrɔ” [We are going to have a child], but the progressive with “bɛ ka” doesn’t really work if it’s not literally happening right now ! 
I saw in the Bamadaba not too long ago and this post reminded me of it.