The recommendation comes as Brazil continues to be one of the global epicentres of the pandemic, with more Brazilians dying of the virus each day than anywhere else in the world.

Hospitals are buckling under the strain and stocks of drugs needed for intubating severely ill patients are running perilously low, with Brazil turning to international partners for help with emergency supplies.

"If it's possible, delay pregnancy a little until a better moment," Health Ministry official Raphael Parente said during a news conference on Friday.

He said the recommendation was partly due to the stress on the health system but also due to the more easily transmissible Brazilian variant known as P.1.

"The clinical experience of specialists shows that this new variant acts more aggressively in pregnant women," Parente said.

Previously, COVID-19 cases during pregnancy were focused on the final trimester and birth, whereas lately there have been more serious cases in the second and occasionally first trimester, he said.

Parente did not give any more details.

The P.1 variant, first discovered in the Amazon city of Manaus, has quickly become dominant in Brazil.

It is thought to be a major factor behind a massive second wave of infections that has brought the country's death toll to more than 350,000 - the second highest in the world behind the United States.

Australian Associated Press