The very, very first one was done at CHOP in 1998. The MOMS trial (the first systematic, randomized trial to look at outcomes of the surgery, there were 3 or 4 surgical centers in the trial) started in 2003 (there were something like 200 surgeries before MOMS, but they weren't systematically compared to other children with postnatal repairs at the same time). The MOMS trial ended early in 2010 or 2011, because it was so successful and at that point the surgery started branching out into other places beyond the trial. That would be around the time your friends had it done, so it would still be considered very cutting edge at the time (since so few surgeons actually could do it), but there were surgeons who had been doing it for over a decade at that point.

It's right at the point now where many places think of it as the standard of care of the mom/child qualify, but a lot of places (especially if not near one of the centers that does it) still recommend postnatal surgery. Lots still think of it as cutting edge these days.

Complicated surgeries that are tricky and take a lot of time to learn take a while to get away from the cutting edge because there just simply aren't enough surgeons at first. It's been amazing to watch the rates that people do this increase (particularly at the center we did it at, which was new at the time).