The advantages of IUD are that it is safe and effective and not easy to fall off, while the disadvantages are that it damages the lining of the uterus and is not easy to remove. 1. Advantages: (1) Safe and effective: IUD is to achieve the purpose of contraception through mechanical stimulation and interference, without inhibiting the normal ovulation of the ovaries, it has no effect on the female endocrine system and avoids the adverse effects of drug contraception, which is safer and more effective, and it does not affect the men and women’s coitus. (2) Not easy to fall off: the shape of the IUD is close to the shape of the uterine cavity, so it is not easy to fall off after placing, and it can be placed for a long time, up to about 20 years. 2. Disadvantages: (1) Damage to the uterine lining: the IUD is a foreign body when it is placed in the uterine cavity, which may damage the uterine lining and cause uterine adhesions and uterine infections, which may cause discomfort such as low back pain, leucorrhea, and a small amount of vaginal bleeding. (2) It is not easy to take out: the IUD does not have a tail wire, so it is inconvenient to remove the IUD, and it is also easy to become incarcerated. Women should choose the right type of birth control ring according to their own situation, and go to the hospital in time to avoid delaying their condition if they feel uncomfortable after taking the ring.