Perinatal Risks Associated with Early Vanishing Twin Syndrome following Transfer of Cleavage- or Blastocyst-Stage Embryos

Abstract

Objective. To investigate whether the perinatal risks associated with early vanishing twin (VT) syndrome differ between cleavage- or blastocyst-stage embryo transfers (ET) in fresh in vitro fertilization (IVF) cycles. Methods. Retrospective, single-center, cohort study of IVF cycles with fresh cleavage- or blastocyst-stage ETs resulting in a live singleton birth. The incidence of preterm birth (PTB), low birth weight (LBW), and very low birth weight (VLBW) was compared between cleavage- and blastocyst-stage ET cycles complicated by early VT. Results. 7241 patients had live singleton births. Early VT was observed in 709/6134 (11.6%) and 70/1107 (6.32%) patients undergoing cleavage-stage and blastocyst-stage ETs, respectively. Patients in the blastocyst-stage group were younger compared to the cleavage-stage group. The cleavage-stage group had a similar birth weight compared to the blastocyst-stage group. There was no difference in the incidence of PTB (9.87% versus 8.57%), LBW (11.1% versus 11.4%), or VLBW (1.13 versus 1.43%) when comparing the cleavage-stage early VT and blastocyst-stage early VT groups, even after adjustment with logistic regression. Conclusions. Our study highlights that the adverse perinatal risks of PTB, LBW, and VLBW associated with early VT syndrome are similar in patients undergoing cleavage-stage or blastocyst-stage ETs during fresh IVF cycles.

Influence of cryopreservation on perinatal outcome after blastocyst‐ vs cleavage‐stage embryo transfer: systematic review and meta‐analysis

“…The incidence of preterm birth before 37 weeks was investigated in 13 studies 2,9,10,12,24,[28][29][30][31][32][33][34][35] (blastocyst stage, n = 90 150; cleavage stage, n = 103 677). A significantly higher risk of preterm birth in singletons born after blastocyst-than after cleavage-stage embryo transfer was revealed by the overall effect size (RR, 1.10 (95% CI, 1.01-1.20); P = 0.04, I 2 = 81%) and subgroup analysis of fresh embryo transfer cycles (RR, 1.15 (95% CI, 1.05-1.25); P = 0.002, I 2 = 58%) ( Figure 2).…”

“…Low birth weight (< 2500 g) was investigated in 11 studies 9,10,12,24,[28][29][30][31][32]34,35 (blastocyst stage, n = 87 353; cleavage stage, n = 101 613). The rate of low-birth-weight neonates was similar in singletons born after blastocystand cleavage-stage embryo transfer irrespective of the cryopreservation procedure used ( Figure S1).…”

“…LGA, large-for-gestational age; PM, perinatal mortality; PTB, preterm birth; Retro, retrospective; SGA, small-for-gestational age; VLBW, very low birth weight; VPTB, very preterm birth. 34 ** * *** 6 Ginström Ernstad (2016) 10 **** ** *** 9 Chambers (2015) 9 **** ** *** 9 De Vos (2015) 29 *** * *** 7 Maxwell (2015) 2 *** * *** 7 Ishihara (2014) 12 **** ** *** 9 Oron (2014) 24 *** * *** 7 Zhu (2014) 36 *** * *** 7 Dar (2013) 28 **** ** *** 9 Fernando (2012) 30 ** ** *** 7 Kalra (2012) 31 **** ** *** 9 Martin (2012) 33 **** * ** 7 Schwarzler (2004) 35 ** * *** 6…”

“…Only first author of each study is given. 29 Ginström Ernstad (2016) 10 Ginström Ernstad (2016) 10 Chambers (2015) 9 Fernando (2012) 30 Ishihara (2014) 12 Ishihara (2014) 12 Kalra (2012) 31 Li (2017) 32 Martin (2012) 33 Maxwell (2015) 2 Oron (2014) 24 Pereira (2016) 34 Schwarzler (2004)…”

“…Very low birth weight (< 1500 g) was evaluated in seven studies 10,12,24,[28][29][30]34 (blastocyst stage, n = 44 122; cleavage stage, n = 54 148) and the incidence of congenital anomalies in four studies 10,24,28,33 (blastocyst stage, n = 8737; cleavage stage, n = 36 097). There was no significance difference in the rate of very low birth weight or congenital anomalies between blastocyst-stage and cleavage-stage transfers, irrespective of the cryopreservation procedure used ( Figures S2 and S3).…”