Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response. Nerve fibres of the parasympathetic nervous system arise from the central nervous system. Specific nerves include several cranial nerves, specifically the oculomotor nerve, facial nerve, glossopharyngeal nerve, and vagus nerve. Three spinal nerves in the sacrum (S2-4) also act as parasympathetic nerves.
A healthy BMI is considered to be between 18.5 and 24.9. Based on these BMI tables, the National Heart, Lung and Blood Institute suggests that a healthy weight range for women who are 5 feet 4 inches tall is 110 to 140 pounds.
One-fifth of pregnant women in the United States are obese, and more and more doctors are advising them to watch their weight if they want an easy pregnancy and a smooth delivery. In May, the Institute of Medicine issued guidelines lowering the minimum recommended weight gain for obese women to 11 pounds, from 15. Now, a large four-year trial called the Healthy Moms study is going further, trying to keep obese pregnant women from gaining any weight at all. If they do gain weight, researchers want it limited to 3 percent of their baseline weight, about 5 pounds for a woman who weighs 170 pounds.