Comparison of Low- and High-Dose Oxytocin Infusions after Delivery on Maternal Hemodynamic and Hematologic Parameters: A Randomized Clinical Trial

Azmoude, Elham; Zamani, Maryam; Khorashadizadeh, Fatemeh; Salari, Zohre; Feyzi Laein, Hediyeh

doi:10.22038/jmrh.2026.93055.2849

Comparison of Low- and High-Dose Oxytocin Infusions after Delivery on Maternal Hemodynamic and Hematologic Parameters: A Randomized Clinical Trial

Articles in Press

Document Type : Original Research Article

Authors

elham azmoude ¹

Maryam Zamani ²

Fatemeh Khorashadizadeh ³

Zohre Salari ⁴

Hediyeh feyzi laein ⁵

¹ Instructor of Midwifery, School of Nursing and Midwifery, Torbat Heidariye University of Medical Sciences

² Department of Midwifery, Neyshabur University of Medical Sciences, Neyshabur, Iran

³ Department of Epidemiology and Biostatistics, Neyshabur University of Medical Sciences, Neyshabur, Iran

⁴ Assistant Professor, Fellowship of Maternal-Fetal Medicine, Neyshabur University of Medical Sciences, Neyshabur, Iran

⁵ Medical Student, Students Research Committee, Neyshabur University of Medical Sciences, Neyshabur, Iran

10.22038/jmrh.2026.93055.2849

Abstract

Background & aim: Postpartum hemorrhage is a major cause of maternal mortality. Oxytocin is routinely used for its prevention, yet the optimal infusion dose that balances uterine efficacy and maternal hemodynamic stability remains uncertain. This randomized clinical trial aimed to compare the effects of low-dose (10 IU) versus high-dose (60 IU) oxytocin infusion on maternal hemodynamic parameters during the first two hours postpartum and on hematologic indices up to six hours after delivery.
Methods: In this triple-blind, randomized clinical trial, 60 healthy primiparous women at term undergoing vaginal delivery were assigned to receive either low- (10 IU) or high-dose (60 IU) oxytocin infusion immediately after delivery. Maternal hemodynamic parameters, including blood pressure and heart rate, were monitored up to two hours postpartum, and hemoglobin and hematocrit were measured at admission and six hours postpartum. Data were analyzed using both descriptive and inferential statistics, with linear mixed-effects models employed to assess dose effects over time.
Results: Participants had a median age of 21 years (IQR 19.25–25.50), and baseline demographic and clinical characteristics were similar between groups (p > 0.05). Hemoglobin and hematocrit decreased significantly from admission to six hours postpartum in both groups (p < 0.001), with no significant differences between low- and high-dose oxytocin. Maternal heart rate and body temperature did not differ significantly between groups (p > 0.05). Although transient changes in systolic and diastolic blood pressure were observed at 15 minutes postpartum, overall pressures and mixed-effects analysis showed no dose-dependent effects (p > 0.05).
Conclusion: Low- and high-dose oxytocin are equally effective and safe for maintaining maternal hemodynamic stability and hematologic indices in the early postpartum period. Clinically, the lowest effective dose is recommended to ensure adequate uterine contraction while minimizing potential side effects. Future studies should evaluate a broader range of doses with extended monitoring to optimize postpartum oxytocin administration.

Keywords

Oxytocin

Hemoglobin

Hematocrit

Blood Pressure

Heart Rate

Subjects