Nuchal Fold Thickened at 20 weeks

Had our 20 week anatomy scan yesterday and everything looked great except the nuchal fold was thickend to 7mm. Baby was also transverse and breech so we weren't able to fully see the heart and 1/2 the face. Doc told us the NF is a soft marker for Downs. Due to us already doing the NIPT testing they said the baby wouldn't have Downs. They didn't say what could be the causes, so I of course came home and Googled. We have to go back within 4 weeks to have another scan to hopefully see the rest of the baby (heart and face). Has anyone had similar experiences? My husband says he isn't worrying until they give him something to worry about, but he hasn't don't any of the reading on it. I'm just praying everything is okay. 😭