# Efficacy of Transdermal Nitroglycerin Patch for the Arrest of Preterm Labor: A Retrospective Study

## TL;DR

This study found that transdermal nitroglycerin patches can effectively delay preterm labor, extending pregnancy by nearly a month, though some side effects were reported.

## Contribution

The study provides empirical evidence on the efficacy of transdermal nitroglycerin patches in arresting preterm labor.

## Key findings

- Transdermal nitroglycerin patches prolonged pregnancy by an average of 28.63 days.
- 90% of patients experienced pregnancy prolongation to at least 48 hours after patch application.
- 92% efficacy rate in inhibiting preterm contractions was observed.

## Abstract

Background

Transdermal nitroglycerin (NTG) is a potent smooth muscle relaxant acting as a tocolytic agent by acting on the uterine muscles. The transdermal patch allows for continuous and controlled release of NTG through the skin into the bloodstream. This method offers the advantage of sustained drug delivery over a prolonged period.

Objective of the study

The study aimed to evaluate the efficacy of NTG patches for the arrest of preterm labor.

Materials and methods

This retrospective study comprised 100 patients admitted to our tertiary care center, ranging from 27 to 35 weeks of gestation, exhibiting preterm labor, uterine contractions, effacement, and dilatation of the cervix, without comorbidities and complications.

Results

In this study, it was observed that the incidence of preterm labor was higher among women aged 21-25 years. Pregnancy duration was extended by an average of approximately 28.63 days in our study cohort, with 90% of patients experiencing a prolongation of pregnancy to 48 hours after the application of a transdermal NTG patch. Parity distribution showed 50% of patients having a parity of G2-G4 and 30% being primigravida. However, 40% of the participants reported experiencing side effects, including headaches (15%) and local reactions (25%), while 60% did not experience any adverse effects.

Conclusion

In this study we found that the application of transdermal NTG patches led to a mean prolongation of pregnancy by 28.63 days, allowing time for the administration of steroids and fetal maturation. The inhibition of preterm contractions was successful, with an efficacy rate of 92%. These findings suggest the potential effectiveness of transdermal NTG patches as a tocolytic agent in managing preterm labor. However, the occurrence of side effects highlights the importance of careful monitoring and management during treatment.