First trimester pregnancy loss after fresh and frozen in vitro fertilization cycles

Objective To characterize risks for early pregnancy loss after fresh and frozen IVF cycles and to investigate whether risk is modified by infertility diagnoses or transfer of embryos in fresh versus frozen cycles. Design Retrospective cohort study using data from the National Assisted Reproductive Technology (ART) Surveillance System. Setting Fertility centers. Patient(s) Clinical pregnancies achieved with fresh and frozen IVF cycles between 2007 and 2012 (N = 249,630). Intervention(s) None. Main Outcome Measure(s) First trimester pregnancy loss. Result(s) A diagnosis of uterine factor was associated with an increased risk of loss in women aged 40 years and younger ( Conclusion(s) Uterine factor had the largest increased risk of loss among infertility diagnoses, although the magnitudes of all risks were small. When transferring embryos of similar quality, the risks of loss were similar between fresh and frozen cycles.