Roe (and later Casey, et al) protects abortion throughout all 9 months.
That's not how I read Roe (granted that was a while ago). If my faulty memory is still good, Roe took more of a balancing test approach where the rights of the fetus were taken into consideration, a right vested in the states to make reasonable laws restricting abortion in the second and third trimesters. As time progressed, the states had more and more power to restrict the practice of abortion.
This decision makes sense in the framework of Roe v. Wade. I am sure once the decision is released, the majority will cite Roe in making their case upholding partial birth abortions.
Wasn't Casey about parental notification?
No, Roe only protects the first trimester, Doe vs. Bolton covered the whole nine months by introducing the health exemption. But that’s gone by the boards now, this ruling basically says that ones health must actually be in danger to qualify. Previously, health meant whatever the baby butcher said it did.