Research suggests COVID-19 Delta variant increases risk of stillbirth or death in the US

on 23 November 2021

Researchers in the United States (US) have found that pregnant women who contract the COVID-19 Delta variant have an increased chance of stillbirth or dying during childbirth.

The studies, conducted by the US Centers for Disease Control and Prevention, aimed to expand current studies on COVID-19 in pregnancy which examined the rates of stillbirth and pregnancy-related deaths throughout the pandemic.

Researchers analysed approximately 1.2 million pregnancies and found that stillbirths had increased during the pandemic between March 2020 and September 2021.

Prior to COVID-19, the still birth rate was 0.59% in the US, increasing to 0.98% in women who contracted COVID-19 during pregnancy. After the Delta variant was found in July 2021, this increased to 2.7%.

The second study looked at the impact COVID-19 has on pregnancy-related deaths in Mississippi. It found the death rate from pregnancy-related complications increased to nine deaths per 1,000 births in women who contracted the virus, compared to 2.5 deaths per 1,000 births in women of reproductive age who were not infected.

Researchers found 15 COVID-related deaths among women who were pregnant or had given birth within 90 days between March 2020 and October 2021. Most of them had at least one chronic medical condition, but none were fully vaccinated.

Nine of the women died after the Delta variant emerged and six died prior to the summer in 2020.

12 of the 15 who died were Black or Hispanic. Black women accounted for 43% of all births in the time period analysed and Hispanic women accounted for 5%.

In the discussion of the research it says: “This analysis adds to growing evidence of an association between COVID-19 in pregnancy and stillbirth, highlights that the risk for stillbirth associated with COVID-19 is affected by maternal morbidity, and demonstrates that the risk has increased during the Delta period.” It also recommends the need for further investigation in COVID-19 and its impact on pregnant women.

The study ‘Risk for stillbirth among women with and without COVID-19 – at delivery hospitalization – United States’ can be found here.