Effect of 17 α-Hydroxyprogesterone Caproate on the Prevention of Preterm Labor: A Randomized Controlled Trial Study

Based on the previous reports, treatment with 17 α-Hydroxyprogesterone caproate (17-OHPC) decreased the risk of preterm labor (PTL). However, some studies indicated contrasting results. This study aimed to investigate the effect of 17-OHPC on the prevention of PTL.

This randomized controlled trial was performed on singleton pregnant women with a history of PTL referring to Imam Khomeini Hospital, Sari, Iran. The experimental group was subjected to an intramuscular weekly injection of 250 milligrams of 17-OHPC from week 16 to 37 of gestational age (n=50). The control group received routine prenatal care. Data were collected using a self-structured checklist, and analyzed using SPSS software (version 18) through independent T-test, Mann-Whitney U test, and the Chi-square test.

The mean age of the experimental and control groups were 24.4±2.6 and 25±2.38 years, respectively. According to the results, there were no significant differences between the groups regarding the risk of PTL less than 35 and 37 completed weeks (P=0.21, P=0.23). Furthermore, a significant relationship was observed between the use of 17-OHPC and birth weight (P<0.05). The frequency of birth weight less than 2500 g in the experimental group was significantly lower than that in the control group (RR:1.56, 95% CI:1.6-2.29, P=0.023).

The results of the outcome analysis based on the separation of gestational age and birth weight in the case and control groups showed no significant differences between the groups regarding the risk of PTL less than 35 and 37 completed weeks.