My SIL was on strict hospitalised bedrest with her stitch from 19w, and they were goign to let her go home at 32w after the steroid shots at 31w. She went into labour that they couldn't stop at 31w5d and she had a c/s. It turned out when they got inside her that a previous c/s scar was so close to rupturing they had to deliver early otherwise it wouldn't have been pretty. But she apparently had the uterus of a 40yo from her two previous pregnancies and losses (and she was only 25.....) so she was really a worst case scenario.