Date of Award

January 2022

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Angela Montgomery



Lucille Kohlenberg and Angela Montgomery, MD, MSEd. Section of Neonatal-Perinatal Medicine, Department of Pediatrics, Yale School of Medicine. New Haven, CT.

Single-family room (SFR) NICUs have gradually replaced open-bay (OB) units over the last three decades. Compared to OB units, SFR units provide increased opportunities for parental rooming and maternal breast milk (MBM) provision; however, they may also present fewer sensory exposures and parental learning opportunities. Due to the presence of potentially beneficial and detrimental effects, it remains uncertain whether the SFR design offers aggregate advantages over the OB model. As such, this study compares the neurodevelopmental outcomes and MBM provision rates in infants cared for in OB and SFR NICUs.

This study is a retrospective chart review that compares outcomes between infants born at ≤ 34 weeks and hospitalized in an OB (n=121) or an SFR (n=105) NICU. Outcome measures were analyzed via the Student’s t-test, linear regression, and logistic regression for binary data.

This analysis found no differences between the OB and SFR cohorts in Bayley-III cognitive, language, or motor composite scores. However, infants in the SFR group scored lower on the fine motor subscale (9.6 vs 8.6; p = <.05) than OB infants and more often scored at least one standard deviation below the mean in two or three composite areas (4.3 vs. 17.9%; p < .05). MBM provision was similar between the OB and SFR groups on day of life 28 but decreased by NICU discharge, markedly so in the SFR group (55.3 vs. 40.0%; p < .05). No differences were noted in growth outcomes during or post-hospitalization. Independent of NICU design, infants with longer NICU lengths of stay had significantly lower developmental cognitive and language scores.

Infants in the SFR NICU had a greater number of neurodevelopmental scores at 12 months of age in concerning ranges and received less MBM by discharge compared to OB infants. Independent of NICU design, MBM provision is associated with higher language scores, and increased NICU length of stay is associated with lower cognitive and language scores, thus suggesting that mediators beyond the NICU environment itself modulate neurodevelopment.


This thesis is restricted to Yale network users only. It will be made publicly available on 06/29/2023