What is the chance for a pregnancy with Trisomy 13 to miscarry?
A large number of babies with trisomy 13 will die while still in the mother's womb and be born still. Studies suggest a 44-66% risk for fetal death in utero when the baby has trisomy 13, most often late in the 2nd trimester or early in the 3rd trimester of pregnancy. The chance for survival to delivery increases with gestational age.
Cereda, A and Carey, J.C. The trisomy 18 syndrome. Orphanet J Rare Dise. 2012; 7:81