It varies greatly from woman to woman, and from foetus to foetus. Some just might “dislodge” in certain cases, but others definitely won’t, even under extreme circumstances. See, for example, Richard Tanner West, who as a foetus survived a skydiving accident that sent him plummeting to Earth and onto concrete at 50 mph. His mother, Shayna, was unknowingly pregnant at the time of the accident. Despite four surgeries and innumerable drugs to patch his mother up, Richard West was born full term (or near to) on June 17, 2006, weighing 7 lbs, 13 oz, perfectly intact and well; he’s now a “happy, healthy” 8-year-old. Wikipedia (because I don’t want to link directly to Fox News, the first site that popped up when I Googled this case): https://en.wikipedia.org/wiki/Shayna_Richardson.