A reduction in premature births during COVID-19

By Jenny Cunningham, Research Advisor on 24 July 2020 Maternity Services Premature Birth Covid-19

A remarkable reduction in premature birth has been found in two studies. Although neither have yet been published in peer reviewed journals, the findings from Ireland and Denmark are receiving plenty of interest. The findings of both studies show a dramatic reduction in the numbers of premature births during lockdown.

The Danish study compared the month of complete lockdown with the same period during the five previous years. The findings showed that the rates of extremely premature birth fell by 90%. The study from Ireland, researchers called ‘a natural experiment’, looked at the reduction in very low birth rate infants (<1.5kg) in one health board. The findings were that there was a 73% reduction in these babies January to April 2020 compared to the same period of the previous 19 years. Lockdown did not occur until 12 March, but from mid-February the Irish Government was issuing guidance around hand washing and social distancing measures.

Preterm birth is the single biggest cause of neonatal mortality and morbidity in the UK. Some 60,000 babies (around seven per cent of live births) in England and Wales are born preterm and globally the figure is 15 million babies. One in four preterm births in the UK are planned due to maternal complications, while three in four happen spontaneously. Reasons for spontaneous premature labour and birth include multiple births, infection and vascular disease. Risk factors include previous preterm birth, black ethnicity, periodontal disease and low body mass index. A short cervical length and a raised cervical-vaginal fetal fibronectin concentration are the strongest predictors of spontaneous preterm birth.

There is speculation in the papers and on social media about why the numbers of premature babies might have decreased and whether the same pattern has been seen in other countries.

Discussion about the possible causes includes:
• Reduced air pollution
• Fewer traffic accidents
• Reduced chances of infection due to lockdown measures, including improved hand washing and social distancing
• Staying at home which may have increased rest and partner support for some women
• Reduced monitoring and in person appointments meant that some women were not induced for complications (although this is unlikely to have affected very early preterm births)

However, other aspects of lockdown, which are known risk factors for premature birth are:

• Increased levels of domestic abuse
• Increased stress and anxiety for some women
• Increased poverty for some families

There is currently no consensus, and women will have had differing experiences depending on where they live, their ethnicity and the support from family and the state. But the findings from these two studies suggest that we may be able to reduce the numbers of preterm births if further research explores what made the difference to the lockdown cohort of women. This work will give some hope to parents and clinicians that we might take a step forward in reducing the numbers of preterm births.