1, genetic reasons: It is genetic factors that determine the primary colors of nipple or labia majora and labia minora. Young women who have no experience in pregnancy or childbirth are born with dark labia. 2, sexual life is too frequent: in the process of sexual life, the labia is repeatedly stimulated by external friction for a long time, which increases local pigmentation and its color will deepen with time. This is a normal physiological phenomenon, and at the same time, the melanin of hormones will make the labia darken and halo appear during sexual stimulation. 3. Normal pigmentation: The color of female genitalia is affected by its own melanin precipitation, and this pigmentation is also related to female hormones. The depth of this color varies from person to person and is related to the amount of pigment. Women with whiter skin will be slightly pink at birth, with darker skin and darker pudendal pigment at birth. Second, although everyone thinks pink is cute, pink means not mature enough, and a mature woman is a black nipple. So nipple blackening means you are a mature woman! In addition, there is another possibility that the breast becomes black, that is, the woman is pregnant. Careful women will find a series of changes in the breast after pregnancy: at first, the breast will increase, and then it will become solid and heavy. There will be a feeling of fullness and tingling in the breasts. Small particles on the dark yellow areola around the nipple are particularly prominent. Black nipples will give off more black luster. Third, the inner skin of the thigh root actually we don't have to feel sad or indecent at all, because your inner thigh, which we often say, is affected by hormones like sex organs, so it is easier to turn black. In fact, this is a normal phenomenon and a personal physiological relationship, so don't worry too much. In addition, it is also possible that your underwear is too tight on weekdays, which oppresses the blood circulation. In the case of poor blood circulation, melanin is easy to sink and the skin color will become darker. At this time, it is recommended to wear loose underwear to relieve the skin on the inner thigh. ● Bleaching surgery for private parts: also called laser bleaching, which means using laser to bleach private parts. The advantage is quick effect, but the disadvantage is unnatural color. It takes a long time to recover after the operation, and there is still pain. According to personal physique, the color will slowly recover in 3 to 6 months, and the price is a bit high, ranging from 3000 to 1000 yuan for private parts. Mainly concentrated in plastic surgery hospitals. Preoperative preparation for bleaching red surgery: 1. Do not take aspirin two weeks before surgery; 2. At the time of initial diagnosis, the doctor should be truthfully informed of his own health condition so as to confirm the operation plan; 3. Before the operation, make sure that you are healthy and have no infectious diseases or other inflammations; 4. Women are not allowed to have overall surgery during menstruation, pregnancy and lactation for 6 months; Bian Xiao reminded: Because of the special position and important role of private parts, red bleaching requires higher technical level of experts. Therefore, it is necessary to choose professional, formal and authoritative plastic surgery hospitals and experts with rich clinical experience, so that the surgical effect is more guaranteed. ● Bleached red cream: A bright red cream containing lycopene, just like a pigment, will change color when painted. The advantage is that it takes effect quickly and turns red when painted. The price is relatively cheap. The disadvantage is that the color is fake, not the natural ruddy color of the skin, and it will fade when touched, or it is difficult to wash off. At present, most products on the market are of this kind. Bian Xiao reminds: The skin around private parts is very delicate and delicate, so you must be careful when choosing, so as to avoid allergic phenomena caused by choosing inferior cream. In addition, many products on the market contain pigments, essences, compounds, heavy metals, hormones and other ingredients. Some products also contain kojic acid and salicylic acid. In recent years, medical research has found that long-term use of kojic acid may lead to cell poisoning, chromosome variation, skin lesions and liver cancer, so it should be used with caution.