Hopes of finding a treatment for foetal growth restriction have been dashed after a much-vaunted trial of VIAGRA's effect on the condition proved the drug to be ineffective. A University of Liverpool-led international clinical trial involving 135 pregnant women, found that Sildenafil, commonly called VIAGRA, did not prolong pregnancy, improve survival, or reduce short-term neonatal morbidity as was hypothesised.
Foetal growth restriction (or intrauterine growth restriction, IUGR), occurs when the placenta has failed to develop correctly. There is no current treatment available for IUGR; the only management option obstetricians can offer is early birth. Because survival for IUGR babies depends on the birthweight and the number of weeks they are at birth, a medication that can improve weight or prolong the time to deliver could have significant advantages for very sick babies.
Researchers from the University's Institute of Translational Medicine set up the STRIDER Trial in 2014 to examine whether Sildenafil, which causes blood vessels to relax and has been used for many years for the treatment of male erectile problems, could cause the blood vessels supplying the placenta to relax and improve the blood supply to the placenta in IUGR pregnancies. It was thought that improving the blood supply to the placenta should improve the growth and well-being of the IUGR baby.
As part of the study researchers recruited 135 women from 19 foetal medicine units in the UK who were less than 30 weeks into their pregnancies with an IUGR baby. Randomly 70 of the women were prescribed Sildenafil and 65 women a placebo.
The results of the trial, which have been published in The Lancet Child & Adolescent Health, found that when Sildenafil was administered to pregnant women with a severely growth-restricted fetus, it did not prolong pregnancy, improve survival, or reduce short-term neonatal morbidity.