A Comparison of Nifedipine Versus a Combination of Nifedipine and Sildenafil Citrate in the Management of Preterm Labour

Cureus. 2023 Jul 25;15(7):e42422. doi: 10.7759/cureus.42422. eCollection 2023 Jul.

Abstract

Background Preterm delivery is a significant contributor to neonatal and infant morbidity and mortality. Preventive methods are preferable to treatment protocols for reducing perinatal mortality and morbidity. The calcium channel blocker nifedipine has the potential to be employed as a tocolytic, whereas the phosphodiesterase inhibitor sildenafil citrate promotes smooth muscle relaxation. Objective This study aims to examine the tocolytic effect of nifedipine in combination with sildenafil citrate in managing preterm labour (PTL). Methods After approval from the ethical board, 160 patients fulfilling the selection criteria were enrolled in the study from the outpatient and emergency department of obstetrics and gynaecology, University of Lahore, Pakistan. After taking written informed consent, their demographic profile, i.e., name, age, gestational age at presentation, parity, and expected date of delivery was noted. Patients were randomly assigned in a 1:1 ratio to two study groups (Group A: sildenafil citrate + nifedipine) and (Group B: nifedipine) using a computer-generated random number table to obtain a trial sequence. In group A, each patient was given nifedipine 20 mg orally, followed by 10 mg orally every eight hours for 48 hours and vaginal administration of sildenafil citrate, 25 mg at eight-hour intervals, for 48 hours. In group B, females were given nifedipine 20 mg orally, followed by 10 mg orally every 8 hours for 48 hours. They were kept admitted for 72 hours. SPSS Statistics version 21.0 (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp.) was used to enter and analyse the collected data. Mean and standard deviation was calculated for quantitative variables like age, gestational age at presentation, gestational age at delivery, and BMI. Frequency and percentage were calculated for parity and preterm delivery. Results The study involved 160 patients, with the average age in Group A being 29.60±4.9 years and in Group B being 30.96±4.98 years. In terms of gestational age at delivery, Group A had an average of 34.16±1.7 weeks, while Group B had an average of 33.5±1.8 weeks (p-value<0.05). Preterm delivery was observed in 68.5% of Group A and 41.3% of Group B, with a significant p-value of 0.001. The study also discovered that the duration of prolonged pregnancy was significantly higher in Group A compared to Group B, with averages of 14.96±10.37 days and 10.24±8.97 days, respectively (p-value=0.002). Conclusion The results of this study suggest that the combination of sildenafil citrate and nifedipine may offer a promising new approach to improving pregnancy outcomes in cases of PTL. In the present study, sildenafil citrate plus nifedipine showed a significant effect in the management of PTL and prolongation in mean gestational age at delivery.

Keywords: gestational age; premature preterm labour rupture of membranes(pprom); preterm birth prevention; qtc prolongation; s: preterm labour; spontaneous preterm delivery.