[user104658]

There's a combination of factors for pregnant women that make covid a larger concern, coming from both sides, so it's really a very complicated balancing act. The immune system in pregnancy is altered (in order to not reject the growing fetus, which only has half of the mother's DNA so would be at risk of being identified as a problem by a "normal" immune system and that means that just because something is safe for the rest of the population doesn't mean it's safe for pregnant women. Important to note that it's not even that pregnant women aren't immune-suppressed... they are immune-altered so it's not even the same as testing in the immune-suppressed.

On the other hand, the later stages of pregnancy shift internal organs into the chest cavity and limit lung capacity, meaning that if severe symptoms of Covid (or any other respiratory illness) kick in, the pregnant woman is more at risk of respiratory failure. In the very-late stages of pregnancy MUCH more at risk as lung capacity can be very low.

So there are additional risks of vaccination over the average member of the public... but on the other hand, there are additional Covid risks over the average member of the public too. An unenviable position to be in really.