Comparison of early pregnancy and neonatal outcomes after frozen and fresh embryo transfer in ART cycles

Abstract

Purpose Frozen embryo transfer (FET) has no clear negative impact on neonatal outcome compared with fresh embryo transfer (ET) and appears to result in similar or even better neonatal outcome. The objective of this study was to compare early pregnancy outcome and neonatal health of children born after FET and fresh ET. Methods In this study early pregnancy and neonatal outcomes after FET (n=200) and fresh ET (n=500) were compared. Results For early pregnancy, biochemical pregnancy was comparable between FET and fresh ET groups. Spontaneous abortion was significantly higher in FET (14.5%) than fresh ET group (9%). Neonatal outcome was comparable between both groups except for lower live birth rate in FET (55%) versus fresh ET group (66%). Conclusion FET has similar neonatal outcome in terms of prematurity, low birth weight, stillbirth, neonatal death and major malformation compared with fresh ET.

Pregnancy Rate After Fresh Embryo Transfer Versus Vitrified-Thawed Embryo Transfer Cycles: Minia University Experience

“…On the contrary to our results, Aflatoonian et al (3) found that spontaneous abortion rate in FET group was significantly higher than in fresh ET group .…”

“…Basirat et al, 2016 (1) documented non-significant difference of the biochemical pregnancy rate (23% in FET versus 18.8% in fresh embryo transfer). Alike, Aflatoonian et al, (3) reported that biochemical pregnancy rate was 27% (54200/) in the FET group versus 22.1% (122500/) in the fresh embryo transfer group.Also, Check et al 16 obtained a significantly higher pregnancy rate in frozen-thawed embryo than fresh embryo transfer in recipients patients (63.4 versus 43.6 %) attributed to the absence of high serum Estradiol in the recipients patient.…”

“…FET provides several benefits in ART such as increasing cumulative pregnancy rate, decreasing the risk of multiple pregnancy by increasing the use of SET and it also reduces hyperstimulation syndrome 3 . Some description that women who use cryopreservation have a better prognosis, with good ovarian reserve 4 .…”

Obstetric and perinatal outcomes in singleton pregnancies resulting from the transfer of frozen thawed versus fresh embryos generated through in vitro fertilization treatment: a systematic review and meta-analysis

“…Although there have been concerns about the impact of cryopreservation on the health of children born, outcome data after frozen ET have been generally reassuring (3). Results of a number of observational studies (4)(5)(6) indicate that obstetric and perinatal outcomes in pregnancies resulting from cryopreserved embryos are similar to those in fresh IVF/ intracytoplasmic sperm injection (ICSI) cycles, whereas other investigators suggest that they are superior (7,8). Currently, there are no randomized controlled trials that have compared obstetric and perinatal outcomes after elective cryopreservation of all embryos followed by delayed transfer versus fresh ET in an IVF/ICSI cycle, which is the current practice in almost all IVF units.…”

Elective freeze-all embryos: What is the scientific evidence?

“…17 However, there were some studies reporting no difference of live birth weight between fetuses after FTET and FET. 18,19 Some results of studies related to the perinatal/obstetric outcome may be inconsistent, and they are mainly observational studies, thus it is considered that more randomized controlled studies are needed in the future. According to the 2017 Cochrane systemic review, FTET was associated with fewer miscarriages, a higher birth weight of singleton babies, and an increased rate of pregnancy complications.…”