On March 25 this year, Karolinska University Hospital introduced screening for covid-19 of all women admitted for childbirth.

In this way, researchers have been able to analyze the outcome for the women who were tested positive in relation to those who did not carry the virus.

- Just carrying the virus does not seem to involve any risk to either the woman or the child, says Mia Ahlberg, midwife and researcher at Karolinska Institutet.

Between March 25 and July 24, 2,682 women were admitted to the hospital for childbirth.

Of these, a total of 156 women, corresponding to 5.8 percent, tested positive for sars-cov-2, as the virus is called.

Screened all

Mia Ahlberg and her colleagues matched the two groups of women in terms of age, BMI, number of previous pregnancies, level of education, disease status and country of birth.

They then analyzed the occurrence of possible birth complications, such as major bleeding, premature birth and care period.

The researchers also compared the children's apgar scores, ie the score scale where the child's health is assessed on the basis of various parameters, such as respiration and heart rate.

The study, which is now presented in the journal Jama, shows, among other things, that two out of three women who carried the virus did not show any symptoms at all.

Furthermore, the researchers could not see any significant difference between the two groups, either in terms of birth complications or apgar scores.

May look different for those who get sicker

This is a bit at odds with other research that shows that pregnant women who react to the virus and become ill with covid-19 risk both their own and the child's health.

- There are studies that show that it can lead to worse outcomes.

But we screened everyone who was admitted.

It is important to remember.

In this way, we caught everyone who carried the virus and 65 percent of them did not show any symptoms at all.

And it was when we compared women who carried the virus, with or without symptoms, with women who did not carry the virus that we saw no difference.

Carrying only the virus thus does not seem to involve any risk to either the mother or the child, while it may look different for those who become more ill, says Mia Ahlberg.

Have you analyzed the group of women who had symptoms?

- We will do it, even if that group is probably a little too small.

But if the virus had been very dangerous for pregnant women, in the same way as sars or mers is, then we would probably have seen it.