I have recently discovered the reason why pregnant women wear overalls--regular pants don't fit and maternity pants, with nothing to grab onto but gravity, fall down. Overalls stretch out and hold on not by any usual pant-holding mechanism like hips or butts but via the sturdy, steadfast, non-morphing shoulders.
Would that I would be caught dead in them. But who knows? Maybe the sheer physics of the pants will persuade me?