Pregnant women, get a flu shot, say researchers from Sweden. New research shows that getting influenza while pregnant is worse than not getting the flu vaccine, and the vaccines are a part of promoting safe and healthy pregnancies.

It is already known that flu shots do not harm pregnant women. They don't cause an increased risk of miscarriage, nor do they cause any pregnancy-related complications. Now, studies are looking into how the vaccinations may affect the unborn child.

The Swedish researchers followed 70,000 women for nearly 7 years to examine if there was a risk that a flu shot during a pregnancy could cause autism spectrum disorder (ASD) in the child. ASD and autism are developmental disorders that “... affect[s] communication and behavior,” according to the National Institute for Mental Health.

There is, however, a high risk for pregnant women to get seriously ill from the flu. And not only can the virus can harm the fetus, the fever caused by the flu can contribute to birth defects, such as spina bifida or cleft lip.

In the study, of the nearly 30,000 children whose mothers did not get vaccines, 1.1% developed an ASD; of the nearly 40,000 children whose mothers were vaccinated while they were pregnant, 1% developed an ASD.

The researchers followed the children for over 6 years. According to Autism Speaks, although children can be diagnosed as young as 2 years, most are diagnosed after age 4.

But what are the risks of contracting the flu? In 2009, The New York Times reported on a 35-year-old mother who contracted the H1N1 flu and became extremely sick. She lost her pregnancy. “She survived near-failure of her kidneys, then her lungs, damaged by continuous high-pressure oxygen, began collapsing,” the Times reported. The mother had not been vaccinated, as there was no vaccine against the H1N1 flu available during her pregnancy.

The mother had a C-section at 27 weeks and the baby lived for 7 minutes. This was an extreme case, but even the regular seasonal flu can be incredibly dangerous to pregnant women.

Getting the flu shot may be even more important this year as COVID-19 continues to spread across the world. Both the flu and COVID-19 have similar initial symptoms: cough, fever, muscle aches and fatigue. If a pregnant woman develops these symptoms and has not been vaccinated against the flu, heatlhcare providers must treat her as if she has COVID-19 until it is ruled out. And, it is possible to contract both viruses at the same time.