title: Reply of the authors.
authors.affiliation: Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland.
authors.forename: Micah J
authors.initials: MJ
authors.lastname: Hill
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Heitmann
authors.forename: Eric D
authors.initials: ED
authors.lastname: Levens
mesh_terms: D000022:Abortion, Spontaneous / Q000175:diagnosis*; D053624:Blastocyst Inner Cell Mass / Q000166:cytology*; D046149:Embryo Culture Techniques / Q000379:methods*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D056826:Single Embryo Transfer / Q000379:methods*