Impact of preimplantation genetic testing on obstetric and neonatal outcomes: a systematic review and meta-analysis

Abstract

To investigate whether preimplantation genetic testing (PGT) increases the risk of adverse obstetric and neonatal outcomes. Systematic review and meta-analysis. Not applicable. Pregnancies achieved after PGT or invitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). Systematic search of databases until December 2020 with cross-checking of references from relevant articles in English. Obstetric and neonatal outcomes after PGT and IVF/ICSI, including mean birth weight, low birth weight, very low birth weight (VLBW), mean gestational age at birth, preterm birth, very preterm birth, birth defects, intrauterine growth retardation (IUGR), sex ratio, cesarean section, hypertensive disorders of pregnancy, gestational diabetes mellitus, placenta disorder (placenta previa, placenta abruption, placenta accreta), and preterm premature rupture of membranes. Ultimately, a total of 785,445 participants were enrolled in this meta-analysis, and these participants were divided into a PGT group (n = 54,294) and an IVF/ICSI group (n = 731,151). The PGT pregnancies had lower rates of low birth weight (risk ratio [RR] 0.85, 95% confidence interval [CI] 0.75 to 0.98), VLBW (RR 0.52, 95% CI 0.33 to 0.81), and very preterm births (RR 0.55, 95% CI 0.42 to 0.70) than those of IVF/ICSI pregnancies. However, the PGT group had a higher rate of the obstetric outcome of hypertensive disorders of pregnancy (RR 1.30, 95% CI 1.08 to 1.57). The PGT did not increase the risk of other adverse obstetric and neonatal outcomes, such as those associated with mean birth weight, mean gestational age at birth, birth defects, IUGR, sex ratio, cesarean section, gestational diabetes mellitus, placental disorder (placenta previa, placenta abruption, placenta accreta), or preterm premature rupture of membranes. We performed subgroup analysis with only blastocyst biopsies and found that PGT with blastocyst biopsies was associated with a lower rate of VLBW (RR 0.55, 95% CI 0.31 to 0.95). The PGT with blastocyst biopsies did not increase the risk of other adverse obstetric and neonatal outcomes. Additionally, we performed subgroup analysis with only frozen-thawed embryo transfer cycles, and we found that PGT pregnancies were associated with a lower rate of VLBW (RR 0.55, 95% CI 0.31 to 0.97), a lower rate of cesarean birth (RR 0.90, 95% CI 0.82 to 0.99), a higher rate of preterm birth (RR 1.10, 95% CI 1.02 to 1.18), and a higher rate of IUGR (RR 1.21, 95% CI 1.06 to 1.38) than those of IVF/ICSI pregnancies. The PGT with frozen-thawed embryo transfer did not increase the risk of other adverse obstetric and neonatal outcomes. The pooled analysis suggested that PGT did not increase the risk of adverse obstetric outcomes. The association between PGT and a higher risk of IUGR requires further investigation.