Difference in birth weight of consecutive sibling singletons is not found in oocyte donation when comparing fresh versus frozen embryo replacements

This study comparing siblings from OD cycles, and eliminating the independent variables that affect early events in pregnancy, revealed no difference in duration of gestation and live birth weights between fetuses obtained after the replacement of fresh or frozen embryos. Moreover, no clinical, phenotypic, or laboratory factors appeared to be relevant, once statistically controlled.