Symptoms that occur during the developmental period are called developmental manifestations, and 10-year-old girls usually have the development of secondary sexual characteristics, reproductive organ development and height development. 1. Development of secondary sexual characteristics: After entering puberty, 10-year-old girls may experience the development of secondary sexual characteristics, first of all, breast development, followed by the growth of pubic hair and armpit hair, as well as widening and enlarging of the buttocks, and so on. 2. Reproductive organ development: After entering puberty, the ovaries and uterus will gradually grow larger, and the fallopian tubes will gradually thicken. With the completion of development, the uterus and ovaries and other reproductive organs will gradually mature, and at this time, the ovaries can produce follicles and menstruation will occur. 3. Height development: After entering puberty, female height and weight will grow rapidly and gradually reach adult female height. After puberty, girls should strengthen their nutrition to avoid stunting. If you find any physical discomfort, please go to a regular hospital and consult a specialist for guidance.