Journal of Midwifery and Reproductive Health

Journal of Midwifery and Reproductive Health

The impact of Low- versus High-Dose Oxytocin Infusion on Maternal Hematologic and Hemodynamic Parameters after Vaginal Delivery: A Randomized Triple-Blind Clinical Trial

Document Type : Original Research Article

Authors
Maryam Zamani 1
Fatemeh Khorashadizadeh 2
Hediyeh Feyzi Laein 3
Zohre Salari 4
Elham Azmoude 5
1 BSc Community Midwife, Royal London Hospital, Barts Health NHS Trust, London, United Kingdom
2 Assistant Professor, Department of Epidemiology and Biostatistics, Neyshabur University of Medical Sciences, Neyshabur, Iran
3 Medical Student, Students Research Committee, Neyshabur University of Medical Sciences, Neyshabur, Iran
4 Assistant Professor, Fellowship of Maternal-Fetal Medicine, Neyshabur University of Medical Sciences, Neyshabur, Iran
5 Assistant Professor, Department of Midwifery, School of Nursing and Midwifery, 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. Although oxytocin is routinely used for prevention, optimal dose balancing uterine efficacy and maternal hemodynamic stability remains uncertain. This trial compared the impact of low-dose versus high-dose oxytocin infusion on maternal hematologic and hemodynamic parameters after vaginal delivery.Methods: This randomized, triple-blind clinical trial was conducted on 60 primiparous women undergoing vaginal delivery at a teaching hospital affiliated with Neyshabur University of Medical Sciences, Neyshabour, Iran in 2024. Participants were randomly allocated 1:1 to low-dose (10 IU) or high-dose (60 IU) oxytocin infusion immediately after delivery. Hemoglobin and hematocrit were measured at admission and six hours postpartum. Blood pressure and heart rate were monitored for two hours postpartum. Data were analyzed using linear mixed-effects models.
Results: Participants had a median age of 21 years (interquartile range, 19.25–25.50 years), with similar baseline characteristics between groups. Maternal heart rate and body temperature showed no significant differences in two groups (P > 0.05). Although transient changes in systolic and diastolic blood pressure occurred at 15 minutes postpartum, mixed-effects analysis showed no dose-dependent effects (P > 0.05). Hemoglobin and hematocrit decreased significantly from admission to six hours postpartum in both groups (p < 0.001), with no significant between-group differences.
Conclusion: Low- and high-dose oxytocin infusion resulted in comparable maternal hemodynamic and hematologic outcomes during the early postpartum period. These findings support using the lowest effective dose to maintain uterine contraction while minimizing potential adverse effects.
Keywords
Oxytocin
Hemoglobin
Hematocrit
Blood Pressure
Heart Rate
Body Temperature Postpartum Hemorrhage
Subjects
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Journal of Midwifery and Reproductive Health
Volume 14, Issue 4
Autumn 2026
Pages 5767-5778