Ongoing pregnancy

Data is sometimes reported as ongoing pregnancies instead of live births to expedite publication timelines. An ongoing pregnancy is defined as one that has progressed beyond a certain point—often after 12 weeks—when the likelihood of miscarriage is greatly reduced, though the specific timeframe can vary between studies.

The metric “ongoing pregnancy/live birth” combines ongoing pregnancies with live births into a single figure. Since the risk of loss is low after the 12-week mark, this combined metric typically provides a good approximation of the live birth rate.