Severity rate in pregnant women is considerably higher: new coronavirus (COVID-19)

In the new coronavirus, the risk of severe COVID-19 is originally lower in women than in men, but it has been reported that pregnant women have a much higher rate of severity.
https://www.cdc.gov/mmwr/volumes/69/wr/mm6944e3.htm?s_cid=mm6944e3_w

Pregnant women between the ages of 15 and 24 have tripled the risk of those who must receive invasive ventilation (95% CI: 1.6 – 5.7),
and in pregnant women between the ages of 35 and 44, increase by 3.6 times (95% CI: 2.4 – 5.4).