Fresh versus frozen embryo transfer has no effect on childhood weight

Childhood growth of term singletons born after frozen compared with fresh embryo transfer

“…No other statistically significant differences were found (Green et al, 2013). In a recently published retrospective cohort from the USA (Ainsworth et al, 2019), the growth of children born after FET (n = 49) and fresh embryo transfer (n = 87) was similar up to the age of 5 years, but loss to follow-up was significant, with only six children in the FET group and 18 children in the fresh embryo transfer group measured at 5 years.…”

“…A few studies have described the growth of children born after FET, fresh embryo transfer and natural conception, and the evidence has been mostly reassuring. Some contradictory findings, however, with unclear clinical significance, have been reported (Wennerholm et al, 1998;Green et al, 2013;Hann et al, 2018;Ainsworth et al, 2019;Turner et al, 2020;Magnus et al 2021).…”

Perinatal and obstetric outcomes in singleton pregnancies following fresh versus cryopreserved blastocyst transfer: a meta-analysis

“…Moreover, the paper by Wei et al (2019) was not included because the authors did not distinguish between singleton and twin pregnancies. Other papers were excluded because they did not meet the inclusion criteria for this review (Aflatoonian et al, 2016;Ainsworth et al, 2019;Belva et al, 2008;Bodri et al, 2018;Fauque et al, 2010;Hwang et al, 2019;Jing et al, 2016;Kaser et al, 2015;Kato et al, 2012;Keane et al, 2016;Li et al, 2015;Litzky et al, 2018;Luke et al, 2017;Maas et al, 2016;Maheshwari et al, 2016;Menezo et al, 1999;Shapiro et al, 2016;Shi et al, 2012;Takahashi et al, 2005;Wang et al, 2010, Wennerholm et al, 2013Xiong et al, 2019a;Zhang et al, 2018, Zhu et al, 2018 (Supplementary Table 2). Lastly, the Xiong et al (2019b) study was not cited because it includes blastocysts obtained from cryopreserved cleavage stage embryos.…”

Is Embryo Cryopreservation Causing Macrosomia—and What Else?

“…In their retrospective cohort study, evaluating the effect of fresh, compared with frozen embryo transfers on neonatal and pediatric weight and weight gain trajectory, Ainsworth et al (30) have confirmed the association between frozen embryo transfer and increased birth weight, but the association did not persist when controlling for confounding maternal factors. Moreover, they found no effect of fresh vs. frozen embryo transfer on neonatal weight and childhood weight gain trajectory.…”