Mass. Gen. Laws ch. 112, § 12N

If a pregnancy has existed for 24 weeks or more, no abortion may be performed except by a physician, and only if in the best medical judgement of the physician it is: (i) necessary to preserve the life of the patient; (ii) necessary to preserve the patient's physical or mental health; (iii) warranted because of a lethal fetal anomaly or diagnosis; or (iv) warranted because of a grave fetal diagnosis that indicates that the fetus is incompatible with sustained life outside of the uterus without extraordinary medical interventions.