London, Aug 17 (IANS): Contracting Covid-19 infection during pregnancy can increase the risk of premature birth by 60 per cent.

The study, led by researchers from the University of California-San Francisco, showed that pregnant women who test positive for virus were more likely to deliver their baby 37 weeks or earlier, the Daily Mail reported.

Researchers also found that Asian women (240 per cent more likely to give birth very preterm) and American Indian women (170 per cent more likely to give birth preterm) were most likely to experience a premature birth.

However, the biological reason why Covid can cause preterm births is not known yet.

The study, published in The Lancet Regional Health, included data from more than 240,000 birth from July 2020 to January 2021.

Nearly 9,000 women had tested positive for the virus at some point during their pregnancy, while the rest made up a control group, the report said.

Some even had very preterm births, in which a baby is born less than 32 weeks into pregnancy.

The risk of preterm or early term delivery after Covid infection was between 10 per cent and 40 per cent, the report said.

Diabetes and obesity also increased the risk of premature birth.

Premature birth could have many long and short term negative effects on a child, including cognitive issues, cerebral palsy and underdeveloped organs.

The team urged pregnant women to get vaccinated against Covid-19 to potentially prevent giving birth prematurely.