Transdermal Nitroglycerin and Nifedipine in Preterm Labor

One of the important complications of pregnancy is preterm labor (PTL) and delivery. There are different tocolytic agents to enhance the time of delivery. The aim of this study was to compare the effect of transdermal nitroglycerin (glyceryl trinitrate, GTN) and oral nifedipine for managing preterm labor. This was a randomized clinical trial in women admitted with diagnosis of PTL. Group one have received transdermal GTN whereas group two have received oral nifedipine, vital signs, FHR, contractions, dilation and effacement as well as gestation age at the time of delivery have been monitored and evaluated in both groups of patient. Our main goal has been delay of delivery to have the most beneficial effect of primary corticosteroid administration for fetus.

transdermal GTN (Schwarz Pharma AG, Monheim, FRG) were prescribed and placed on the patient forearm. Each patch contained 37.4 mg of glyceryl trinitrate which was released in blood stream (10mg/24hour). After one hour of the first patch application, the uterine contractions were evaluated.

For the nifedipine group, nifedipine 5mg softgel (Daana Pharma Co., Tabriz, Iran) was prescribed. In this group, the order of medicine prescription was as below; One softgel every 20 min (4 doses) Two softgel every 6 hr (4 doses) One softgel every 6 hr (4 doses) One softgel every 8 hr (3 doses) Likewise, the uterine contractions were checked every one hour and if the contraction didn't subside or there was any change in dilation and effacement, the treatment were stopped and another tocolytic were applied.

The Apgar scale is determined by evaluating the newborn baby on five simple criteria on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10. The five criteria are summarized using words chosen to form a backronym (Appearance, Pulse, Grimace, Activity, Respiration). The Apgar scale is determined by evaluating the newborn baby on five simple criteria on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10. The five criteria are summarized using words chosen to form a backronym (Appearance, Pulse, Grimace, Activity, Respiration).

Inclusion Criteria: GA between 24 to 34 weeks early-onset signs of delivery (≥4 uterine contractions during 20 minutes, ≥1 centimeters (cm) of dilation and effacement over 80%). Exclusion Criteria: maternal or fetal life-threatening conditions which require emergency termination multiple pregnancy premature rupture of membrane fatal anomaly or intra-uterine fetal death cervical dilation ≥4 cm any tocolytic treatment in previous days and positive allergy to GTN

Wilson A, Hodgetts-Morton VA, Marson EJ, Markland AD, Larkai E, Papadopoulou A, Coomarasamy A, Tobias A, Chou D, Oladapo OT, Price MJ, Morris K, Gallos ID. Tocolytics for delaying preterm birth: a network meta-analysis (0924). Cochrane Database Syst Rev. 2022 Aug 10;8(8):CD014978. doi: 10.1002/14651858.CD014978.pub2.