Would hysterectomy be justified for contraceptive reasons if and only if pregnancy is 100% guaranteed to be fatal for both mother and child?
A hysterectomy could be done if there were a medical problem with the uterus itself that endangered the life of the mother (e.g., cancer, unstable or ruptured uterus). In such a case sterilization would be an unintended side effect and therefore the procedure would be morally licit. But a hysterectomy cannot be performed if the intention itself is sterilization, which appears to be the case in the hypothetical situation posed. A woman facing such a situation should contact the organizations listed below for help in determining licit courses of action that would do what is possible to protect her life.
That Celibate Bachelor Was Right!** by Rachel Fay