The pitch is brilliant, I wonder what led this doctor to start this experiment? What gave him the idea? What was his motivation? And this is probably the biggest problem with this film, we know almost nothing about the main character. Is the doctor the main character by the way?
While it is cool to get to know a bit more with the more or less colorful moms, this movie spends either too much or too little time on those characters; to the point that we don't get invested enough to empathise and too invested for the comic relief of their flat character. This only time it works is with the young employee who is high 24h a day, there's no depth to his character, but that's ok because we don't get to see much of him. He is only here and there for comedy.
Another issue with Kitty Mammas is that the stories of the future moms are mostly irrelevant to the main story. Yes, they have an important role in the eyes of the doctor, but aside from getting to know about their motivation, there is no need to dig in their daily lives and battles. Focusing on the soon to be moms gives a chance to get some comedy, which is good most of the time.
This movie has some fun times and is worth the watch, it's just too bad it gets lost exploring irrelevant side stories.