Several frequent flyer programs around the world let you put your status on pause, or extend your status, when you experience major life events. It’s not nearly as common in the U.S., perhaps because we’re not as focused here on accommodating new births or medical issues as people are in Europe or Australia.
It makes all the sense in the world for a travel loyalty program, though. A customer who was incredibly valuable before having a child is likely to be incredibly valuable once the get back on the road.