Am J Perinatol
DOI: 10.1055/a-2184-1294
Original Article

Urgent Follow-up after Outpatient Nonstress Tests and the Potential for Fetal Monitoring at Home

Alissa Dangel
1   Mother Infant Research Institute, Tufts Medical Center, Boston, Massachusetts
Priyanka Shindgikar
2   Tufts University School of Medicine, Boston, Massachusetts
Andrew Polio
3   Department of Obstetrics and Gynecology, Tufts Medical Center, Boston, Massachusetts
Janis L. Breeze
4   Tufts Clinical and Translational Science Institute, Tufts University, and Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, Massachusetts
1   Mother Infant Research Institute, Tufts Medical Center, Boston, Massachusetts
› Author Affiliations
Funding This study was supported by the Tufts Medical Center COVID-19 Rapid Response Seed Funding Program. The project described was supported by the National Center for Advancing Translational Sciences, National Institutes of Health, Award Number UL1TR002544 (U.S. Department of Health and Human Services, National Institutes of Health, National Center for Advancing Translational Sciences, Award no.: UL1TR002544; Tufts Medical Center COVID-19 Rapid Response Seed Funding Program).


Objective This study aimed to measure the proportion of patients needing urgent clinical follow-up after an abnormal outpatient nonstress test (NST). We further sought to capture the patient perspective on the acceptability of performing NSTs at home.

Study Design A retrospective cohort study was performed over a 2-year period to determine the frequency of abnormal NSTs in a hospital-based, antepartum testing unit in patients greater than or equal to 32 weeks' gestation. The proportion of patients who delivered within 24 hours of an abnormal NST was also determined. A cross-sectional, web-based patient survey was conducted to obtain insight into the patient's comfort level with potentially performing NSTs at home.

Results The chart review yielded 665 patients who underwent 2,122 NSTs at greater than or equal to 32 weeks. Of the 2,122 NSTs, 111 were categorized as abnormal and required urgent clinical follow-up, or 5.2% (95% confidence interval [CI] 4.3, 6.3%). Of the 665 patients, 13 delivered within 24 hours of an abnormal NST, or 2.0% (95% CI 1.0, 3.3%). In the web-based survey, the proportion of respondents who would feel comfortable or very comfortable conducting NSTs at home was 87/125, or 69.6% (95% CI 60.9, 77.1%).

Conclusion This study revealed that 5.2% of NSTs performed in a hospital-based antepartum testing unit were abnormal and required urgent clinical follow-up. Of the patients being followed in the antepartum testing unit, 2.0% delivered within 24 hours of an abnormal NST. The majority of the survey respondents indicated they would feel comfortable performing NSTs at home. The present study adds important information regarding the risks and benefits of NSTs at home.

Key Points

  • Telehealth for NSTs offers advantages over in-person NSTs.

  • The proportion of NSTs that need urgent follow-up was 5.2%.

  • A majority of patients are interested in telehealth for NSTs.

  • Guidelines are needed before adoption of telehealth for NSTs.

Publication History

Received: 12 June 2022

Accepted: 26 September 2023

Accepted Manuscript online:
29 September 2023

Article published online:
01 November 2023

© 2023. Thieme. All rights reserved.

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