The first menstrual period occurs after the onset of pubertal growth, and is called menarche. FSH regulates the development, growth, pubertal maturation and reproductive processes of the human body. A intake is one of the etiological factors in delayed pubertal maturation. The development of gynecomastia is usually associated with benign pubertal changes. The same associations with hormone levels were not demonstrated in females undergoing pubertal development. Bleeding before the onset of pubertal development deserves evaluation. However, 75% of pubertal gynecomastia cases resolve within two years of onset without treatment. Anorexia nervosa can also result in pubertal delay or arrest. The highest rates of IGF-1 production occur during the pubertal growth spurt. Female blue crabs mate only once in their lifetimes during their pubertal, or terminal, molt. Anorexia nervosa is more likely to occur in a person's pubertal years. Sei whales for instance are divided into categories such as immature, pubertal and mature. Gluten challenge is discouraged before the age of 5 years and during pubertal growth. Widening of the shoulders occurs as part of the male pubertal process. Gluten challenge is also discouraged before the age of 5 years and during pubertal growth.