Placental abnormalities are associated with type of embryo transfer in assisted reproductive technologies (ART). Placental abnormalities are associated with type of embryo transfer in assisted reproductive technologies (ART)

ART is associated with abnormalities in DNA methylation and a higher incidence of adverse pregnancy outcomes in humans and mice. However, which specific exposure, among the interventions utilized during ART, is responsible for these outcomes remains unknown. Embryo transfer after vitrification-thaw (frozen ET) into a maternal hormonal environment more closely resembling unassisted conception is increasingly utilized clinically, but reports suggest a higher incidence of large for gestational age (LGA) infants, with male infants potentially more affected than female infants. Overall design: A prospective cohort study including patients from 2010-2020 was performed and human placentas from singleton pregnancies were obtained after: fresh IVF cycles and programmed frozen embryo transfer cycles

辅助生殖技术（Assisted Reproductive Technology，ART）与DNA甲基化异常及人类、小鼠不良妊娠结局的更高发生率密切相关。然而，在辅助生殖技术所采用的各类干预措施中，究竟是哪一项特定暴露因素引发了上述不良结局，目前仍未明确。将经玻璃化冷冻解冻（vitrification-thaw）后的胚胎进行冷冻胚胎移植（frozen ET），并植入更贴近自然受孕的母体激素环境中，这一临床应用正日益广泛，但现有研究报道显示，该操作会使大于胎龄儿（Large for Gestational Age，LGA）的发生率升高，且男性胎儿受影响的程度可能显著高于女性胎儿。研究设计：本研究为一项前瞻性队列研究，纳入2010年至2020年的受试患者，收集单胎妊娠产妇的胎盘组织，样本分别来源于新鲜体外受精（In Vitro Fertilization，IVF）周期与程序化冷冻胚胎移植周期。