A low basal body temperature in a 48-year-old woman, whether she is menopausal or not, may be caused by a disturbance in the regulation of hormones in the body (including estrogen and thyroid hormones). When a 48-year-old woman is not menopausal, if there is ovarian dysfunction, no ovulation and no formation of the corpus luteum, the basal body temperature will continue to be low, and the menstrual cycle and menstrual flow will be accompanied by abnormalities. If hypothyroidism is induced by low thyroid hormone levels, it can also cause low body temperature. When a 48-year-old woman has gone through menopause, the female gonads and ovaries will decline, and the estrogen and progesterone secreted by them will also decline, resulting in menopausal syndrome, which is characterized by hot flashes and sweating, poor sleep, and agitation, etc. If there is too much sweating, the basal body temperature may be lowered. Of course, we can’t rule out hypothyroidism. Whether or not the 48-year-old woman menopause, the basal body temperature has been low under the circumstances suggest that this time to early medical care, under the guidance of the doctor systematically for sex hormones, thyroid hormones and other appropriate examination, a clear diagnosis and then determine the treatment program.