Intrauterine Devices (IUD/IUS): What Every Woman Needs to Know

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What is an IUD?

An Intrauterine Device (IUD) is a small object that is placed inside a woman’s uterus (womb) for the purpose of preventing or interrupting pregnancy.

Currently, there are two kinds of IUDs available in the United States: the Copper-T IUD, made from plastic and copper, and the Intrauterine System IUS, a plastic device that releases hormones.

Is an IUD 100% effective?

No. Thecopper-T IUD has a clinical pregnancy rate of less than 1 per 100 women each year,1 and the IUS has a rate of 0.2 per 100 women each year.2

How does an IUD work?

IUDs work against pregnancy in several ways. Some of these effects take place before fertilization, and others take place after the sperm and egg have united to form a new human being.

Both the copper-T and the IUS irritate the inner lining of the womb, causing inflammation. This is the same reaction the body has to any foreign object, such as a splinter under the skin. In the reproductive system, inflammation causes some cells to attack and destroy sperm, ova, and any newly formed embryo.3

The IUD does not protect against
sexually transmitted infecctions
including AIDS.

The copper-T IUD also releases copper continuously into the inside of the womb, and the copper spreads into the part of the Fallopian tubes near the womb. This copper can directly poison the ovum or the sperm. If fertilization occurs, the copper can also poison the embryo while it is still in the Fallopian tube, thus causing destruction of a new human life.3

The IUS releases hormones that have several effects in the female reproductive system. In each normal cycle, the womb builds up tissue and chemicals that help with sperm survival and movement and also support implantation (the process by which a new embryo attaches to the womb to obtain nourishment to sustain life). The hormones released by the IUS (a) make the lining of the womb thinner so that sperm do not survive or move as well and, if fertilization occurs, the new embryo usually cannot implant in the mother’s womb, (b) can thicken the cervical mucus, reducing sperm movement and vitality, and (c) cause a small reduction in ovulation (about 15%).3

Does an IUD cause abortion?

Using mathematical models, it has been estimated that a woman using the IUD/IUS will have from about 0.2 to 1.8 abortions (destruction of a new human life) per year caused specifically by the IUD/IUS.3

What are the risks
from using an IUD?

Uterus perforation

Bladder perforation

Spontaneous abortion6

Septic abortion

Pelvic inflammatory disease7

Heavy bleeding

Ectopic pregnancy4

Permanent sterility5

Allergy to copper

Copper toxicity



Ovarian cyst8

Does an IUD have a permanent effect on a woman’s fertility?

The synthetic hormone in the IUS can cause a delay in the return of menstruation and fertility after it is removed.

If perforation or pelvic infection occurs while using the IUD, the uterus or Fallopian tubes may become damaged, thus reducing the possibility of pregnancy.

In cases of perforation of the uterus, a hysterectomy (removal of the uterus) may be required, resulting in permanent sterility.

What are my options?

If you are single, abstinence is the best option and always works!

If you are married, the modern methods of Natural Family Planning (NFP) are the safest, healthiest, and least expensive approaches to family planning.


1. Intrauterine copper contraceptive. Retrieved from
Copper%20Contraceptive. December 13, 2007.

2. Levonorgestrel-releasing intrauterine system. Retrieved from
December 10, 2007.

3. Stanford J MD MSPH. Mechanism of action of intrauterine devices: Update and

estimation of post-fertilization effects.

Am J Obstet Gynecol. December 2002; 187(6).

4. Coste, J, et al. Ectopic pregnancy is again on the increase. Recent trends in the incidence of ectopic pregnancies in France (1992-2002). Human Reproduction 2004; 19(9):2014-2018.

5. PDR® Family Guide to Women’s Health and Prescription Drugs 2004.

6. Spaulding Stephen MD. Issues Birth control intrauterine devices. Retrieved from January 16, 2008.

7. Steen R, Shapiro K. Intrauterine contraceptive devices and risk of pelvic inflammatory disease. Reproductive standard of care in high STI prevalence settings. Health Matters. May 2004; 12(23):136-143.

8. Levonorgestrel-releasing intrauterine system. Retrieved from December 13, 2007.

Intrauterine Devices (IUD/IUS)

Price: $0.35