Pregnant women with mild chronic hypertension can safely be prescribed antihypertensives without compromising fetal growth, US clinicians have declared.

Results from their large, multicentre trial suggest that treating to a target of less than 140/90mmHg cuts the risk of pre-eclampsia and preterm birth by 21% and 13%, respectively.

Lead author and obstetrician-gynaecologist Dr Alan Tita said that “after many decades of uncertainty”, their study findings support the need for clinical guidance for the treatment of both mild (<160mmHg systolic) and severe chronic hypertension in pregnancy.

“To date, there have been disparate recommendations and hesitancy to treat women with milder forms of high blood pressure during pregnancy for fear of hurting the growing fetus but based on the data, doing so may be good for mum and baby,” said Dr Tita, from the University of Alabama Heersink School of Medicine, in Birmingham.