Original Research Preterm Delivery and Low Birth Weight Among Neonates Conceived With Intracytoplasmic Sperm Injection Compared With Conventional In Vitro Fertilization Sanaz Keyhan, MD, Tracy Truong, MS, Yi-Ju Li, PhD, Tia Jackson-Bey, MD, and Jennifer L. Eaton, MD, MSCI OBJECTIVE: To examine the prevalence of prematurity and low birth weight (LBW) among singletons conceived with intracytoplasmic sperm injection (ICSI) compared with those conceived with conventional in vitro fertil- ization (IVF). METHODS: Using the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System, we conducted a retrospective cohort study of women undergoing a first, fresh autologous ICSI or conventional IVF cycle from 2004 to 2013. Singleton live births were included in the analysis. Primary outcomes were preterm delivery and LBW. Secondary outcomes were very pre- term delivery, preterm LBW, term LBW, and very LBW. Logistic regression models and propensity score match- ing were used to compare perinatal outcomes between ICSI and IVF cycles. Subset analyses were performed after stratification by sperm source, male factor infertility, and female prognosis. RESULTS: Of the 90,401 cycles included in the analysis, ICSI was used in 60,719 (67.2%) and conventional IVF was used in 29,682 (32.8%). After propensity score matching and covariate adjustment, the two groups had similar odds of preterm delivery (adjusted odds ratio [OR] 1.02, 95% CI 0.89–1.18) and LBW (adjusted OR 0.92, 95% CI 0.78–1.10). Using the matched data set, subset analyses demonstrated no significant association between the method of fertilization and the examined perinatal out- comes. CONCLUSION: Rates of preterm delivery and LBW were similar between pregnancies conceived with ICSI and conventional IVF after propensity score matching and stratifying by baseline patient characteristics. Pre- viously reported differences in these outcomes were likely secondary to patients’ inherent risk factors rather than the fertilization procedure itself. (Obstet Gynecol 2018;0:1–7) DOI: 10.1097/AOG.0000000000002423 A ssisted reproductive technology (ART) is associ- ated with an increased incidence of perinatal mor- bidity. Studies have shown that neonates conceived with ART are at increased risk of preterm delivery and low birth weight (LBW). 1–3 These risks are largely attributable to multiple gestation; however, rates of preterm delivery and LBW are elevated even among singletons conceived with ART. It is not known which components of ART contribute to adverse perinatal outcomes. For example, it is unknown whether obstetric outcomes differ after intracytoplasmic sperm injection (ICSI), in which a single spermatozoa is injected into each oocyte, and conventional in vitro fertilization (IVF), in which oocytes and sperm are mixed in a dish. Some studies have demonstrated decreased From the Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, and the Department of Biostatistics and Bioinfor- matics, Duke University Medical Center, Durham, North Carolina. Presented at the Annual Meeting of the American Society for Reproductive Med- icine, October 15–19, 2016, Salt Lake City, Utah. The authors thank the Society for Assisted Reproductive Technology (SART) for the data set as well as all SART members for providing clinical information to the SART Clinical Outcomes Reporting System database for use by patients and researchers. Each author has indicated that he or she has met the journal’s requirements for authorship. Corresponding author: Jennifer L. Eaton, MD, MSCI, 5704 Fayetteville Road, Durham, NC 27713; email: jennifer.eaton@duke.edu. Financial Disclosure The authors did not report any potential conflicts of interest. © 2018 by The American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0029-7844/18 Copyright Ó by The American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. VOL. 0, NO. 0, MONTH 2018 OBSTETRICS & GYNECOLOGY 1