Background In vitro methods of conception are associated with adverse perinatal outcomes. It is unclear if the risk of stillbirth is increased also. Objective This systematic review and meta‐analysis aimed to estimate the risk of stillbirth in singleton gestations following in vitro methods of conception compared to non‐in vitro conceptions. Search strategy A comprehensive search in PubMed, Embase, CINAHL, and Cochrane Library was undertaken from database inception to February 2021, with backward citation tracking. Selection criteria Eligible studies included randomized controlled trials, cohort studies, or case‐control studies that assessed stillbirth following in vitro fertilisation and/or intracytoplasmic sperm injection in comparison to non‐in vitro methods of conception, including spontaneous conceptions, intrauterine insemination, and ovarian stimulation. Data collection and analysis The Newcastle‐Ottawa Scale was used to assess risk of bias. A summary odds ratio (OR) for stillbirth following in vitro methods of conception compared to non‐in vitro methods was calculated using a random‐effects model for meta‐analysis. Main results Thirty‐three cohort studies met inclusion criteria. There was an increased risk of stillbirth with in vitro methods: OR 1.41 (95% CI 1.20–1.65); however, the crude baseline risk of stillbirth was low (4.44/1000 total births). Subgroup analysis did not demonstrate an increased risk when in vitro methods were compared to conception without in vitro methods in the context of subfertility. Conclusions Compared to non‐in vitro conceptions, in vitro conceptions have an increased risk of stillbirth. However, there is insufficient evidence to demonstrate whether this risk is associated with in vitro techniques or underlying subfertility. Tweetable abstract This meta‐analysis found an increased risk of stillbirth in singletons from in vitro methods of conception.
We evaluated and compared three different commercial kit immunoassays for alpha-fetoprotein (AFP) before we implemented our neural tube defect screening program. Each kit can be used with either serum or amniotic fluid. Analytical recovery ranges for AFP reference sera within each kit's standard curve limits (in kilo-int. units/L) were 97-108% (7.5-180) for the Kallestad kit, 77-101% (21.8-436) for Amersham, and 92-100% (0-177) for Hybritech. CVs, within each manufacturer's standard-curve limits, for combined intra-assay (amniotic fluid pools) and inter-assay (kit serum controls) averaged 3.6-7.3% (Kallestad), 2.4-9.3% (Amersham (y) kit results showed a correlation of r = 0.97, y = 1.05x + 5.5 kilo-int. units per liter of maternal serum (n = 66; range, 2.0-98.5). Gestational age did not influence these assay correlations. The Kallestad AFP assay demonstrated a maternal serum positivity rate of 2.9% at greater than or equal to 2.5 (n = 655) and 8.9% at less than 0.5 (n = 423) multiples of the median. All kits performed well analytically.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.