Outcomes of neonates born following transfers of frozen-thawed cleavage-stage embryos with blastomere loss: a prospective, multicenter, cohort study

Abstract

BackgroundDespite limited information on neonatal safety, the transfer of frozen-thawed cleavage-stage embryos with blastomere loss is common in women undergoing in vitro fertilization. We aimed to evaluate the pregnancy outcomes and safety of frozen-thawed cleavage-stage embryos with blastomere loss.MethodsThis prospective, multicenter, cohort study included all frozen-thawed cleavage-stage embryo transfer (FET) cycles between 2002 and 2012. Pregnancy outcomes and subsequent neonatal outcomes were compared between FET cycles with intact embryos and those with blastomere loss.ResultsA total of 12,105 FET cycles were included in the analysis (2259 cycles in the blastomere loss group and 9846 cycles in the intact embryo group). The blastomere loss group showed significantly poorer outcomes with respect to implantation, pregnancy, and live birth rates than the intact embryo group. However, following embryo implantation, the two groups were similar with respect to live birth rates per clinical pregnancy. Among multiple pregnancies (4229 neonates), neonates from the blastomere loss group were at an increased risk of being small for gestational age (aOR = 1.50, 95% CI 1.00–2.25) compared to those from the intact group. A similar trend was observed among singletons (aOR = 1.84, 95% CI 0.99–3.37). No associations were found between blastomere loss and the subsequent occurrence of congenital anomalies or neonatal mortality. However, neonates from the blastomere loss group were at an increased risk of transient tachypnea of the newborn (aOR = 5.21, 95% CI 2.42–11.22).ConclusionsThe transfer of embryos with blastomere loss is associated with reduced conception rates. Once the damaged embryos have implanted, pregnancies appear to have the same probability of progressing to live birth but with an increased risk of small for gestational age neonates and transient tachypnea of the newborn.Study registrationThis study was retrospectively registered at Chinese Clinical Trial Registry. Registration number: ChiCTR-OOC-16007753. Registration date: 13 January 2016.Electronic supplementary materialThe online version of this article (10.1186/s12916-018-1077-8) contains supplementary material, which is available to authorized users.

Perinatal outcomes of neonates born from different endometrial preparation protocols after frozen embryo transfer: a retrospective cohort study

“…Details on the use of oocyte retrieval and frozenthawed embryo transfer were abstracted from the patient's hospital records as we previously described [15]. ART procedures were conducted using routine protocols, and information was documented, including the COH protocol, type of insemination, number of oocytes retrieved, the day of embryo transfer, and the number of embryos transferred.…”

Oocyte exposure to supraphysiological estradiol during ovarian stimulation increased the risk of adverse perinatal outcomes after frozen-thawed embryo transfer: a retrospective cohort study

“…Pregnancy outcomes and relevant obstetric outcomes were followed up as previously described. 15 Outcomes measurements and variable specification Participants were interviewed in person to obtain information on sociodemographic characteristics and reproductive history. The height and weight were measured, and body mass index (BMI) was calculated before interview.…”

Effect of embryo cryopreservation duration on pregnancy-related complications and birthweight after frozen-thawed embryo transfer: a retrospective cohort study

“…Our previous study indicated that blastomere loss after embryo thawing could lead to a decreased pregnancy rate after embryo transfer. 21 In addition to blastomere loss, other factors, namely, embryo vitrification, open vitrification systems, and vitrification duration, have raised concern regarding their impacts on pregnancy outcomes and neonatal safety. 15,26,27 Although the long duration of cryopreservation makes it difficult to study the impact of duration on the safety of vitrification, some studies have indicated comparable pregnancy rates for FETs after short-and long-term cryopreservation and reported that birthweight in singletons is not influenced by vitrification duration.…”

“…The patient's clinical data regarding the ART procedure, including oocyte retrieval and embryo transfer, were collected from the patient's hospital records as previously described. 21 ART procedures were conducted per routine protocols, and patient information during the ART procedure, including controlled ovarian hyperstimulation (COH) protocol (gonadotropin-releasing hormone [GnRH] agonist protocol, GnRH antagonist protocol, microflare protocol or other protocol), type of insemination (IVF or ICSI), number of oocytes retrieved (≤10, 11-20 or >20), type of endometrial preparation (natural cycle, HRT cycle, or ovarian stimulation cycle), day of embryo transfer (day 3, day 4, or day 5), and number of embryos transferred (1 or 2), was documented. Endometrial thickness before embryo transfer was measured by highly trained sonographers via transvaginal ultrasound (Acuson X300, Siemens, Germany).…”