Maternal Rest Improves Growth in Small-for-Gestational-Age Fetuses (<10th Percentile)

Authors

Greggory R DeVore
Bardo Polanco
Wesley Lee
Jeffrey Brian Fowlkes
Emma E Peek
Manesha Putra
John C Hobbins

Publication Date

1-1-2025

Journal

American Journal of Obstetrics & Gynecology

DOI

10.1016/j.ajog.2024.04.024

PMID

38842845

PMCID

PMC11579257

PubMedCentral® Posted Date

1-1-2025

PubMedCentral® Full Text Version

Author MSS

Published Open-Access

yes

Keywords

Humans, Female, Pregnancy, Retrospective Studies, Bed Rest, Adult, Infant, Small for Gestational Age, Ultrasonography, Prenatal, Fetal Growth Retardation, Fetal Development, Fetal Weight, Biometry, Head, Gestational Age, Infant, Newborn, abdominal circumference, bed rest, Doppler velocimetry, estimated fetal weight, femur length, fetal growth restriction, head circumference, left lateral recumbent position, longitudinal study, middle cerebral artery, small for gestational age, umbilical artery

Abstract

BACKGROUND: Optimal management of fetuses diagnosed as small for gestational age based on an estimated fetal weight ofHowever, maternal bed rest has not been recommended based on the results of a randomized clinical trial that showed that maternal rest does not improve fetal growth in small-for-gestational-age fetuses. This study was conducted to revisit this question.

OBJECTIVE: This study aimed to determine whether maternal bed rest was associated with an increase in the fetal biometric parameters that reflect growth after the diagnosis of a small-for-gestational-age fetus.

STUDY DESIGN: A retrospective study was conducted on fetuses who were diagnosed as small for gestational age because of an estimated fetal weight of10th percentile. To assess the response to bed rest, the change in fetal biometric parameters (estimated fetal weight, head circumference, abdominal circumference, and femur length) after the recommendation of bed rest was computed for 2 periods: (1) before the diagnosis of a weight of(2) at the time of diagnosis of a weight ofmeasures, proportions were compared using the McNemar test, and percentile values were compared using the Bonferroni Multiple Comparison Test. A P value of

RESULTS: A total of 265 fetuses were observed before and after maternal bed rest. The following were observed in this study: (1) after 2 weeks of maternal rest, 199 of 265 fetuses (75%) had a fetal weight of >10th percentile; (2) the median fetal weight percentile increased from 6.8 (interquartile range, 4.4-8.4) to 18.0 (interquartile range, 9.5-29.5) after 2 weeks of bed rest; (3) similar trends were noted for the head circumference, abdominal circumference, and femur length. In the groups of patients who were not asked to be on bed rest, a reassignment to a weight of >10th percentile at a follow-up examination only occurred in 7 of 37 patients (19%) in the Texas-Michigan group and 13 of 111 patients (12%) in the Colorado group compared with the bed rest group (199/265 [75%]) (P<.001).

CONCLUSION: Patients who were prescribed 2 weeks of bed rest after the diagnosis of a fetal weight of10th percentile in 199 of 265 fetuses (75%). This increase in fetal weight was significantly higher than that in the 2 control groups in which bed rest was not prescribed. This observation suggests that bed rest improves fetal growth in a subset of patients.