@Catherine thank you for your response! yes they referred me to MFM but my appt isn't for another 4 wks so I've been a little anxious. I'm so glad to hear that it resolved on it's own in your son. Did you have to get extra scans throughout?
I did, but not necessarily for that. I'd had covid earlier in pregnancy, so they did monthly and then weekly scans to make sure he was growing well and that his placenta was working well. But I think they would have done some extra for that because they checked it every time until it resolved.
My son had pyelectasis, but it resolved itself around 34ish weeks. They had us speak to a specialist, who went over different risk factors. It's more common in boys than girls, and it typically resolves itself before or shortly after birth. Some cases, however, do require surgery to correct. Are they having you talk to a specialist at all?