Human Chorionic Gonadotropin vs. Magnesium Sulfate (MgSO4) as a Tocolytic Agent: A Randomized Controlled Trial

Objective To compare the efficacy of β-human chorionic gonadotropin (β-HCG) with magnesium sulfate (MgSO₄) as a tocolytic agent in preterm labor. Methodology This randomized controlled trial (NCT05828966) was conducted in the Department of Gynecology and Obstetrics, Shaheed Zulfiqar Ali Bhutto Medical University (SZABMU), Pakistan Institute of Medical Sciences, Islamabad, Pakistan, from February 15 to December 20, 2023 (11 months). All patients fulfilling the inclusion criteria were enrolled. A total of 70 patients with established preterm contractions and labor were included in the study. All patients were divided into groups A and B via a lottery method. HCG was given in Group A in a dose of 5,000 units intramuscular injection, followed by a drip of 10,000 units in 500 mL of dextrose 5%, at the rate of 20 drops per minute. Patients were given 4 g of MgSO₄ in Group B intravenously as a continuous dose, followed by 2 g/hour till uterine quiescence is achieved. Half-hourly assessment of uterine contractions, maternal vital signs, and fetal heart rate monitoring was done.  Results In this study, we enrolled 81 females. There was no significant difference between the overall mean age (25.21 ± 2.992) years, parity (1.49 ± 0.974), and gestational age (31 ± 1.445) years in both groups. HCG had higher patient satisfaction and a lower rate of tocolysis failure within 48 hours compared to MgSO₄ (P-value < 0.001). The HCG group also had a lower rate of preterm labor and lower rates of side effects compared to the MgSO₄ group (P-value = 0.010). However, cesarean section rates were higher in the MgSO₄ group (P-value = 0.025). Conclusions HCG treatment is more effective in preventing preterm labor within the critical first 48 hours of pregnancy. As compared to MgSO₄, HCG exhibits potent tocolysis with the least maternal and neonatal side effects.