Evaluation of clinical efficacy and safety of natural micronized progesterone in prevention of preterm labor: a prospective study at tertiary care teaching hospital in India

Suhani V. Patel, Shahnoor K. Gowani, Sushma R. Shah, Supriya D. Malhotra


Background: Uterine relaxants (UR) are used in management of in Preterm labour (PTL), which is responsible for considerable morbidity and mortality in mother as well as preterm infant. Author are yet to discover an ideal UR which is highly effective yet safe. Literature supports the use of natural micronized progesterone (NP) during threatened PTL. However, little data exists for Indian population. Therefore, present study becomes imperative.

Methods: A comparative clinical study was carried out on 78 patients (aged 19 to 35 years with singleton pregnancy and gestational age between 28 and 37 weeks with cervix ≤4 cm dilated) who were diagnosed with threatened PTL were included. Those who refused treatment were allocated to control group (n= 29) and received only bed rest. NP was given orally 200 mg twice a day to 21 patients and 200 mg intra vaginal twice a day to 28 patients and was continued until delivery or 37 weeks of gestation whichever occurred first. The efficacy was proven if PTL was prevented and patient did not require an alternative UR for ≥48 hours.

Results: The mean age of patients was 23±3.2 years, majority being multipara. Author observed that both oral and vaginal formulation of NP was found to be highly effective (p <0.05) as primary UR and maintenance therapy in preventing PTL as compared to the control group. However, difference between them was not statistically significant. None of the patients were lost to follow-up and no adverse events linked to the treatment were reported.

Conclusions: Although, the data obtained from this study was limited and the sample size was small, findings of this study support the use of NP in prolonging threatened PTL.


Preterm labour, Progesterone in preterm labour, Tocolytics

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