Female baby thick calves may be caused by excessive subcutaneous fat, is a normal physiological phenomenon, no need to worry too much, may also be caused by bone development deformities and other pathological reasons. 1. Physiological phenomenon: because the baby girl after birth, the growth and development of the speed is relatively fast, in the case of adequate nutritional supply, the weight will be rapid growth, thus causing the accumulation of subcutaneous fat, appearing calf thick situation, in general, belong to the normal physiological phenomenon, do not need to worry about, pay attention to the observation can be. 2. Skeletal deformity: If the baby girl has thick calves with non-physiological curvature, it may be caused by pathological causes such as malformation of the leg bones, or it may be caused by abnormal development of local muscle tissues. Female baby calves thick may also have other reasons, such as progressive muscular dystrophy, etc., it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.