It seems that there are health care professionals voicing their concerns over control top tights for pregnant women. My opinion is women should not focus on their appearances, as far as tummy compression goes. It should be entirely about the health of the baby, and then the health of the mother. In most/all cases, the health of both are 1 in the same. So, wear the control top hosiery, if it is healthy, and do not wear it, if it is not. If it is neither healthy nor unhealthy, then do what feels best.
I say this, just to voice my opinion, so that anybody trying to get a sense of what the internet community thinks, can get my opinion.