2.1. Definition. Classification
Pregnancy loss is spontaneous termination of pregnancy from conception until 37 weeks gestation estimated from the first day of the last period. Classification:
1) spontaneous abortion is termination of pregnancy within the period from conception until 21 weeks gestation (included);
2) recurrent pregnancy loss (3 times or more);
3) preterm delivery is termination of pregnancy within the period 22-37 weeks gestation.