A medical trial in the Netherlands has been called to a halt after eleven newborn babies died.
The women in the trial had been taking Viagra during pregnancy to promote their babies' growth in the womb.
The babies had suffered from foetal growth restriction due to an underdeveloped placenta.
Foetal growth restriction can mean a premature birth, a low birth weight and poor chances of survival outside the womb.
There is currently no treatment available for the condition.
It was thought that the babies' development during pregnancy would benefit from the blood flow that Viagra promotes.
A total of 93 women were given sildenafil, the non-brand name for the drug, while 90 took placebo pills, reports
BBC News.
Twenty of the babies developed lung problems after birth, including three from the placebo group.
Eleven of the babies that had been exposed to the sildenafil passed away.
The trial, which was being carried out at 11 hospitals round the Netherlands, was stopped. It had been due to run until 2020.
It was a repeat of previous Viagra trials that had taken place in the UK and in Australia and New Zealand.
These trials showed no harm in administering Viagra to babies with foetal growth restriction, but also no benefit.
