Consensus from my mom/baby group (both from physiology and direct experience) was that it also makes it extremely easy to screw up your lower back.
Ah, more to mind! When I ease back into running again, the plan is to do so super-slowly. Hopefully will mean everything goes ok!
My physical therapist sister-in-law told me that kegals are really easy to incorrectly (and that most people could be considered postnatal even decades later). It may be beneficial to see a PT for a few postnatal appointments to make sure the pilates and strength is done the correct way.
Ditto- I highly recommend PT! Also, you might look into a Serola sacroiliac belt (though someone- i.e. said PT- has to show you how to wear it properly)- it eliminated a lot of pain by pulling my pelvis back together before I trained my muscles to do it themselves.