Does A Fetus Survive With Absence Of Amniotic Fluid At 15th Week?

I have miscarried twice so far. First was a missed abortion at 8-9 Weeks and 2nd was a PPROM at 15 Weeks. . There was complete lose of fluid and later when u/s was done baby had no heart rate. I didn't have any incompetent cervix issues. At round 7-8 Weeks I had SCH and bleeding stopped in 2-3 Days. Please let me know why I miscarried and ways to prevent it in my next pregnancy. Can a fetus survive with no amniotic fluid at 15 weeks? Please help me out.