Maher MA, et al. - Researchers performed a prospective randomized study determining the tocolytic action of nifedipine combined with sildenafil citrate (SC). Further, they compared the efficacy of the combination vs nifedipine alone in inhibiting threatened preterm labour (PTL). From January 2015 to November 2016, 239 women with threatened PTL were randomized to receive either nifedipine with SC or nifedipine alone. They identified more women remaining undelivered in correlation with nifedipine combined with SC (81.8% vs 68.6%) during hospitalisation. This suggests that the tocolytic effect of nifedipine was enhanced using vaginal SC.