Washington: Would-be-mothers, who are at risk of pre-eclampsia, can reduce the chances of premature delivery by taking a low-dose aspirin in first trimester of pregnancy. The study found an 82 percent reduction in the rate of early preeclampsia, resulting in delivery before 34 weeks.

Pre-eclampsia causes the flow of blood through the placenta to be reduced, restricting the flow of oxygen and nutrients to the foetus which could restrict growth. Professor Kypros Nicolaides from King's College London said that the results of the trial offered 'definitive proof' of the effect of aspirin.

"This extensive study is definitive proof that women can take simple measures in the first trimester of pregnancy to significantly reduce their chances of developing pre-term preeclampsia," Nicolaides added. The double blind, placebo-controlled trail of 1,776 women at high risk for pre-term pre-eclampsia found a lower incidence of developing the disease in women taking aspirin than those taking a placebo.

The pregnant women were given a dose of 150mg per day from between 11 to 14 weeks of pregnancy up until 36 weeks. Pre-term preeclampsia occurred in 13 participants (1.6 percent) in the aspirin group, compared to 35 (4.3 percent) in the placebo group.

The results prompted calls for low-dose aspirin to be routinely prescribed to women at risk of the disease. Professor David Wright from the University of Exeter Medical School said that the results show that aspirin can prevent pre-eclampsia in high risk pregnancies. I hope that they will alter clinical practice and improve pregnancy outcomes for mothers and their babies.

An analysis of more than 30 trials investigating the benefit of a dose of 50 to 150 mg of aspirin per day for the prevention of preeclampsia showed that such therapy resulted in a 10 percent lower incidence of preeclampsia. The World Health Organization (WHO) already recommends low-dose aspirin for the prevention of pre-eclampsia in women at high risk and recommends it be started before 20 weeks of pregnancy.

Pre-eclampsia is usually characterised by a sudden increase in blood pressure and protein in the urine, which can occur after the 20th week of pregnancy and often results in pre-term birth. The research appeared in the journal of Medicine.