"Proposed federal legislation would require doctors to provide fetal pain information to women seeking abortions when fetuses are at least 20 weeks old, and to offer women fetal anesthesia at that stage of the pregnancy. A handful of states have enacted similar measures. The review says medical evidence shows that brain structures involved in feeling pain begin forming earlier but likely do not function until around the seventh month, when fetuses are about 28 weeks old. Some scientists say younger fetuses show pain by moving away from a stimulus, but that likely is a reflex action and not an indication that they are actually feeling pain, said UCSF obstetric anesthesiologist Dr. Mark Rosen, the study’s senior author. Offering fetal pain relief in the fifth or sixth month, when brains are too immature to feel pain, is misguided and might result in unacceptable health risks to women, the authors said. Dr. Nancy Chescheir, chairman of obstetrics and gynecology at Vanderbilt University and a board director at the Society of Maternal-Fetal Medicine, said the report “will help to develop some consensus” on when fetuses feel pain. “To date, there hasn’t been any.”"