The number of babies born in January 2021 dropped compared to previous years due to COVID-19 health concerns.

Countries with the strictest lockdowns in early 2020 and over-occupied intensive care units have seen the biggest drops in live births 9-10 months later, according to scientists in Switzerland.

Dr Leo Pomar, the first author of the study and a midwife sonographer at Lausanne University Hospital, Switzerland, said: “The decline in births nine months after the start of the pandemic appears to be more common in countries where health systems were struggling and capacity in hospitals was exceeded.”

“This led to lockdowns and social distancing measures to try to contain the pandemic”, Dr Pomar explained.

“The longer the lockdowns the fewer pregnancies occurred in this period, even in countries not severely affected by the pandemic.”

Live births in England and Wales decreased by 13% in January 2021, in comparison to 2018 and 2019, and in Scotland it dropped by 14%.

The countries that saw the biggest reduction in live births were Lithuania (28%) and Romania (23%).

Researchers found that Sweden, which did not have a lockdown, did not experience a drop in live births, despite having a high number of deaths due to the pandemic.

The duration of lockdowns was the only linking factor that the team found to be associated with the decline in live births in January 2021, compared with January 2019 and January 2018.

Dr Pomar commented: “The association we found with the duration of lockdowns may reflect a much more complex phenomenon, in that lockdowns are government decisions used as a last resort to contain a pandemic.

“Lockdown duration has a direct impact on couples.”

Although birth rates have now seen a resurgence, research shows that March 2021 was the only month on record to have a birth rate on a similar level to the average rate pre-pandemic.

This rebound is still not enough to compensate for the decline in birth rates in January 2021.

Dr Pomar said: “The fact that the rebound in births does not seem to compensate for the decrease in January 2021 could have long-term consequences on demographics, particularly in western Europe where there are aging populations.”

Christian De Geyter, deputy editor of Human Reproduction and professor at the University of Basel, Switzerland, said the data on the impact of lockdowns on couples seeking fertility treatment is not available yet.

Prof De Geyter, who was not involved in the study, commented: “These observations are important because they show that human reproductive behaviour, as evidenced by numbers of live births, changes during dramatic events, epidemics and global crises.”