Effect of maternal cortisol levels on fetal heart rate patterns in primiparous pregnant women in the third trimester

Abstract

SUMMARY OBJECTIVE: This study aimed to determine whether maternal cortisol levels affect fetal heart rate patterns in primiparous pregnant women in the third trimester. METHODS: This cross-sectional descriptive study included 400 primiparous pregnant women with uncomplicated pregnancies between November and December 2022. The study included primiparous pregnant women over 18 years old in the third trimester who had not exercised for at least 2 h before the fetal heart rate monitoring and had a healthy pregnancy without consuming any food or drink. Fetuses with decelerating heartbeats and pregnant women who showed uterine contraction and cervical dilation during the fetal heart rate monitoring were excluded from the study. Research data were collected with the data collection form. The fetal heart rate data were collected using a cardiotocograph. At least two accelerations during the 20-min nonstress test period were the basis for diagnosing a reactive nonstress test. About 5 mL of maternal saliva for cortisol measurements was collected before fetal heart rate monitoring. Research data were analyzed with IBM SPSS Statistics for Macintosh, Version 28.0. A p-value of <0.05 was considered significant. RESULTS: There were no significant differences in the comparison of the groups in terms of education and income status, family type, fetal gender, pregnancy planning status, BMI and age averages, or gestational week averages (p>0.05). The number of at least two accelerations required for the diagnosis of reactive NST was also higher in Group 1 (maternal salivary cortisol level ≤24.20). A moderately positive relationship between fetal heart rate and maternal salivary cortisol was observed (r=0.448, p=0.000). In total, 11.9% of the total change in fetal heart rate level is explained by maternal cortisol (R 2 =0.119). Maternal cortisol increases fetal heart rate level (ß=0.349). CONCLUSION: These findings suggest that stress in primiparous pregnant women with high cortisol levels may influence fetal heart rate patterns. It was revealed that the increase in cortisol level, considered a stress hormone, may be a harbinger of fetal tachycardia.

Comment on “Effect of maternal cortisol levels on fetal heart rate patterns in primiparous pregnant women in the third trimester”

“…First, it is important to note that serum cortisol levels may provide a more accurate reflection of maternal cortisol levels compared to cortisol levels in saliva. As demonstrated in this study 1 , a moderately positive relationship between fetal heart rate and maternal salivary cortisol levels was observed (r=0.448, p=0.000). However, the correlation coefficient of 0.448 between fetal heart rate and maternal salivary cortisol levels suggests a relatively weak association.…”

“…Turan and Kaya’s 1 recent study explores a critical aspect of pregnancy, focusing on the impact of maternal cortisol levels on fetal heart rate patterns among primiparous pregnant women in the third trimester. Their research provides valuable insights into the complex relationship between maternal stress and its potential consequences for fetal well-being.…”

“…Their research provides valuable insights into the complex relationship between maternal stress and its potential consequences for fetal well-being. In this study, Turan and Kaya 1 investigated the correlation between maternal cortisol levels, a hormone linked to stress, and fetal heart rate patterns. Their findings highlight the significance of monitoring and managing maternal stress during pregnancy, as elevated cortisol levels are associated with alterations in fetal heart rate patterns.…”

“…Second, as the primary objective of this study 1 is to explore the impact of maternal cortisol levels on fetal heart rate patterns, it is essential to emphasize that numerous factors are associated with fetal heart rate patterns, not solely maternal cortisol levels. Research by Monk et al 2 has indicated that pregnant women with comorbid depression and anxiety exhibit a greater increase in heart rate compared to controls.…”

“…The evidence suggests that salivary cortisol levels are not the sole influencing factor, and maternal breathing rate and psychiatric status have also been demonstrated to have a significant relationship with fetal heart rate. However, this study 1 lacks detailed information regarding maternal breathing rate and psychiatric status. One plausible hypothesis is that fetal heart rate is an outcome influenced by the combined effects of these three factors, rather than being determined by maternal cortisol levels alone.…”