Circadian changes and sex-related differences in fetal heart rate parameters

Kapaya, Habiba; Broughton Pipkin, Fiona; Hayes-Gill, Barrie; Loughna, Pamela V.

Abstract

BACKGROUND: Previous researchers have studied circadian changes in the fetal heart rate (FHR) on small sample sizes and in a strictly controlled environment. This study was undertaken to investigate these changes during the late second and third trimesters, using a portable fetal electrocardiogram recording device (Monica AN24) in pregnant women in home and hospital environments with unrestricted mobility.
METHODS: This was a prospective cohort study of 54 pregnant women with uncomplicated singleton pregnancies between 25 and 40 weeks gestation. FHR recordings were made up to 16 h at home or in the hospital setting in the United Kingdom. FHR data over 90 min periods were averaged and the day (7:00 am-11:00 pm) and night (11:00 pm-7:00 am) data from the same individual were compared. Data were examined for evidence of sex-related differences.
RESULTS: During the night, there was a significant reduction in basal heart rate (bFHR) and a significant increase in short term variation (STV) and long term variation (LTV) (P < 0.05). Basal FHR decreased (P < 0.002), whereas LTV increased (P = 0.014) with advancing gestation. Male fetuses showed greater day: night variation than females regardless of gestation (P = 0.014). There was a higher bFHR in fetuses monitored during the day in hospital (P = 0.04).
CONCLUSION: This study demonstrates that there are sex-, environment and time-related differences in the FHR parameters measured. These differences may need to be considered taken when interpreting FHR data.

Citation

Kapaya, H., Broughton Pipkin, F., Hayes-Gill, B., & Loughna, P. V. (2016). Circadian changes and sex-related differences in fetal heart rate parameters. Maternal Health, Neonatology and Perinatology, 2(1), https://doi.org/10.1186/s40748-016-0037-6

• Journal Article Type: Article
• Acceptance Date: Aug 25, 2016
• Publication Date: Sep 2, 2016
• Deposit Date: Oct 5, 2017
• Publicly Available Date: Oct 5, 2017
• Journal: Maternal Health, Neonatology and Perinatology
• Electronic ISSN: 2054-958X
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 1
• DOI: https://doi.org/10.1186/s40748-016-0037-6
• Keywords: Circadian, Fetal heart rate, Fetal heart rate monitoring, Electronic fetal monitoring, Fetal electrocardiogram,; Fetal sex, Pregnancy
• Public URL: https://nottingham-repository.worktribe.com/output/819430
• Publisher URL: https://mhnpjournal.biomedcentral.com/articles/10.1186/s40748-016-0037-6
• Contract Date: Oct 5, 2017