PSA...4D ultrasounds

Hi ladies, I just wanted to put this out there. Do your research on 4 D ultrasounds. The FDA has released some facts about possible issues with the 4D ultrasounds being done. My cousin who is a sonographer in the state of MN at a hospital is no longer allowed to do 3D/4D US due to the risk. From the quick reading I did it says that the 3D/4D US can increase the temp of the tissues and cause something called cavitation. It has also been linked to autism some how but I couldn't myself find an article supporting it plus what isn't linked to autism these days. I know the pics are super neat but do your research so you are making an educated decision. I understand that these US are done for diagnostic purposes and most of the time safe, but I think the concern is more so about the private US places that do 30 minute 4D US, but my cousin who works at a hospital had to quit doing them so who knows?