Contraceptive success rate

The success rate of contraception with an IUD is very high, but it is not 100% certain to be successful. It is probably more than 90%. So if you want to prevent yourself from getting pregnant accidentally during sexual intercourse, you can get an IUD. However, this operation does have certain risks. If it falls off, it will lead to contraceptive failure. In addition, you have to choose the size according to your cervical opening.

Insertion of an intrauterine device is an ideal contraceptive method with an effectiveness rate of over 90%. However, a small number of women still get pregnant after insertion for the following reasons:

(1) The intrauterine device has fallen out, but the patient is not aware of it. This is the most common cause of contraceptive failure.

(2) The IUD is placed low, close to the cervix, and cannot inhibit the implantation and development of the fertilized egg.

(3) The size of the intrauterine contraceptive device is not suitable for the size of the uterine cavity, or the device has been deformed or even broken, thus losing its contraceptive effect.

In order to avoid the above situation and reduce the chance of pregnancy with an IUD, you should go to the hospital for regular check-ups, once within 3 months after insertion, and then once a year thereafter. During the inspection, special attention should be paid to whether the IUD pops out. Once it is found to pop out, timely measures should be taken to replace it or switch to other contraceptive measures. Women who have experienced IUD fall off or become pregnant with the IUD should be inspected more frequently after the IUD is inserted again.

1. The copper ions in the copper intrauterine contraceptive ring aggravate the aseptic inflammatory response of the endometrium and interfere with the activity of the enzyme system necessary for implantation, which is not conducive to the implantation of the fertilized egg and the development of the blastocyst.

2. Copper ions may also change the biochemical properties of cervical mucus, affect sperm activity and capacitation, and thus further enhance the contraceptive effect. Copper ions can also directly kill sperm and fertilized eggs.

3. The role of prostaglandins: Long-term stimulation of the IUD causes the endometrium to produce prostaglandins. On the one hand, prostaglandins can enhance uterine contraction and fallopian tube peristalsis, causing fertilized eggs that are not sufficiently developed and divided to be sent to the uterine cavity prematurely, thus affecting implantation.

4. A large amount of prostaglandins can enhance the effect of estrogen, inhibiting the decidual reaction of the endometrium during pregnancy, which is not conducive to the implantation of the fertilized egg.

5. The ring can interfere with the normal cyclic changes of the endometrium, which is not conducive to implantation; it can also affect the transport or capacitation of sperm. Intrauterine devices containing high doses of levonorgestrel may also inhibit ovulation, change the properties of cervical mucus, and hinder sperm penetration.

The mechanism of human pregnancy is that the female ovary releases an egg, the egg is fertilized in the ampulla of the fallopian tube, and then develops into an embryo (morula) in the fallopian tube. The embryo is then released into the uterus to implant and grow. Contraception is about blocking any of these steps.

The contraceptive principle of the intrauterine device (IUD) is: when an embryo wants to implant in the uterus, the constantly moving IUD scrapes the uterine wall, causing aseptic inflammation of the uterus, making it impossible for the embryo to implant and conceive normally in the uterus, thereby causing miscarriage to achieve the purpose of contraception. The essence of an intrauterine contraceptive device (IUD) is a long-term, mild abortion procedure using curettage and abortion, and it is the first choice for Chinese women to use for contraception after marriage.