Figure 1.

Summary of the proposed time-related treatment outcome measures for studies evaluating fertility treatment. Biochemical pregnancy is defined as a pregnancy diagnosed only by the detection of beta hCG in serum or urine; clinical pregnancy is defined as a pregnancy diagnosed by ultrasonographic visualization of one or more gestational sacs or definitive clinical signs of pregnancy; live birth is defined as the complete expulsion or extraction from a woman of a product of fertilization, after 22 completed weeks of gestational age which, after such separation, breathes or shows any other evidence of life, such as heart beat, umbilical cord pulsation or definite movement of voluntary muscles, irrespective of whether the umbilical cord has been cut or the placenta is attached (Zegers-Hochschild et al., 2017). ETP, end time point; RCT, randomized controlled trial; STP, start time point.