The law is written on a false non medical premise, so it’s not possible for any doctor to interpret because it’s nonsense divorced from reality.
There is no such thing as some clear line in medicine between, ah now instead of just grievous injury she will certainly die without an abortion at this point so let’s do it now and she’ll be fine. There may be black and whites at some extreme ends, but mostly there’s just a spectrum of constantly changing grey probabilities.
This is all total fiction that exists only in the head of pro lifers and the people writing these laws. Even if that fiction was reality, there’s a non zero chance that prosecutors will harass people performing abortions anyways, and they’ll bring in their own hack experts saying no that abortion wasn’t necessary, and the judgement is done by a jury of lay people not doctors with medical expertise, good chance the doctors get thrown in jail anyways in this fictional universe pro lifers have created.
There’s just no practical reality where a law that only “protects life of the mother” can exist. Legislators need to stay out of the doctors office and let pregnant individuals make the decisions with the assistance of doctors, only then can the life and health of the mother actually be protected.