Published date: Jun 30 2022

Journal Title: Sudan Journal of Medical Sciences

Issue title: Sudan JMS: Volume 17 (2022), Issue No. 2

Pages: 236–243

DOI: 10.18502/sjms.v17i2.11457

Olufemi Adebari Oloyedeoloyedeoao@gmail.comFetal and Maternal Medicine Unit, Department of Obstetrics and Gynaecology, Olabisi Onabanjo University Teaching Hospital, Ogun State, Nigeria

Mustafa Adelaja LaminaFetal and Maternal Medicine Unit, Department of Obstetrics and Gynaecology, Olabisi Onabanjo University Teaching Hospital, Ogun State, Nigeria

Background: The study aims to establish the pattern of fetal heart rates in the first and second trimesters and determine whether there is a statistically significant difference in the first-trimester fetal heart rate (FHR) of males and females.

Methods: This retrospective observational research is a study of FHRs measured at 11⁺⁰–13⁺⁶ wk and 18⁺⁰–23⁺⁶ wk, and ultrasound scan-diagnosed fetal sex at 18⁺⁰–23⁺⁶ wk. Singleton fetuses with nonambiguous external genitalia were recruited. The FHR was measured in B or M mode with Pulsed Wave Doppler, while ultrasound appearance of external genitalia determined the fetal sex at 18⁺⁰–23⁺⁶ wk. Student’s t-test and Chi-square test were used for data analysis, and statistical significance was set at p < 0.05.

Results: A total of 2437 pregnancies meeting the study criteria were analyzed. The fetal sexes were 1398 (57.4%) males and 1039 (42.6%) females. There was no statistically significant difference in the first-trimester FHR between males and females (p = 0.74). However, females had higher mean FHR in both the first and second trimesters (First trimester: 165.4 ± 18.2 bpm vs 163.2 ± 17.1 bpm and Second trimester: 150.9 ±22.6 bpm vs 141.9 ±23.1 bpm). The FHR reduces with the increase in gestational age.

Conclusion: There is no statistically significant difference in the first-trimester FHRs between sexes.

Keywords: statistically significant difference, fetal heart rates, fetal sexes, first trimester, ultrasound scan

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