A Growing Dilemma: Antenatal Corticosteroids and Long-Term Consequences

Abstract

Objective A single course of synthetic antenatal corticosteroids is standard care for women considered to be at risk for preterm birth before 34 weeks of gestation. While the intended target is the fetal lung, the fetal brain contains remarkably high levels of glucocorticoid receptors in structures critical in the regulation of behavior and endocrine function. Negative programming signals may occur which can lead to permanent maladaptive changes and predispose the infant/child to an increased risk in physical, mental, and developmental disorders.

Methods Framed around these areas of concerns for physical, mental, and developmental disorders, this narrative review drew on studies (animal and clinical), evaluating the long-term effects of antenatal corticosteroids to present the case that a more targeted approach to the use of antenatal corticosteroids for the betterment of the fetus urgently needed.

Results Studies raised concerns about the potential negative long-term consequences, especially for the exposed fetus who was born beyond the period of the greatest benefit from antenatal corticosteroids. The long-term consequences are more subtle in nature and usually manifest later in life, often beyond the scope of most clinical trials.

Conclusion Continued research is needed to identify sufficient safety data, both short term and long term. Caution in the use of antenatal corticosteroids should be exercised while additional work is undertaken to optimize dosing strategies and better identify women at risk of preterm birth prior to administration of antenatal corticosteroids.

Key Points

• A single-course ACS is a remarkable therapy with substantial benefits.

• There is a potential of long-term neurodevelopmental consequences in the ACS-exposed fetus.

• There is a need to improve dosing strategies and identification of appropriate at risk women.

Keywords

antenatal corticosteroids - neurodevelopmental outcomes - long-term outcomes - term infant - preterm infant

Authors' Contributions

E.V.A., K.E.M., and S.G.M. conceptualized the study design. E.V.A. wrote and edited the manuscript. All authors critically revised the manuscript for important intellectual design.

Publication History

Received: 07 June 2020

Accepted: 07 September 2020

Article published online:
14 October 2020

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