The principle is to use some liquid to make vaginal tissue necrotic and scabbed, thus producing a feeling of uterine contraction.

1. Tightening needle is an injection cosmetic plastic surgery method for private parts in the market for tightening vagina.

2. The effect of acupuncture generally lasts for 3 to 6 months, and the specific time varies according to the patient's condition. The best effect is 3 to 6 months after injection, but some patients may need multiple injections to achieve the best effect.