How IUDs Got a Bad Name

During the 1960s and 1970s, IUDs thrived. All of them were made of plastic (polyethylene), with some barium sulfate added so that they would show up on x-rays. The first American IUD, a large device called the Margulies Coil, caused a lot of bleeding and cramping and had a hard plastic tail that male sexual partners often found uncomfortable. The softer Lippes Loop replaced it. Later, the Saf-T-Coil and the short-lived Majzlin Spring came along.

Dalkon Shield became available at the same time as the U.S. Senate was holding inquiries into the safety of oral contraceptives. It was an immediate hit, especially among young women who had doubts about the pill. The year that A.H. Robins began marketing the Shield, the devices accounted for 66 percent of all IUDs sold, and by mid-1973, about 40 percent of all IUDs in use were Shields. By June 1974, when the FDA requested suspension of further sales, 2.8 million women had purchased the device.

Several months earlier, the FDA had urged physicians to remove IUDs immediately from any woman who became pregnant. Their recommendation was based on the fact that 12 IUD users had died after miscarriages left them with severe infections. Ten had the Dalkon Shield in place at the time, and two the Lippes Loop. After physicians began following the FDA's advice, IUD-related death from miscarriages ceased to be a problem. However, these events led to further scrutiny of the Shield, and sparked an explosion of fear and distrust of all IUDs.

The data connecting the Dalkon Shield to miscarriage and even to death seemed overwhelming. Doctors reported that Dalkon Shield users were twice as likely to be hospitalized as other women, and that those who became pregnant while wearing an IUD —especially the Shield—increased their chance of dying by up to 50 times that of women with no IUD in place. Although some scientists pointed out weaknesses in the studies, women still avoided the device.

In the wake of the Dalkon Shield scandal, some researchers began charging that IUDs were also responsible for an increased risk of pelvic inflammatory disease. Initial studies showed that women using other forms of birth control did indeed have a lower rate of PID than did IUD users. Barrier methods blocked bacteria; and the Pill, by thickening the mucus in the cervix, made bacterial entry difficult.

However, when compared with women using no form of contraception at all, IUD users actually have a lower risk of PID. And researchers during the Dalkon Shield period were unaware of what we now know: The greatest risk factor for PID is frequent sex with multiple partners. Since use of IUDs peaked during the sexual revolution of the 1960s and 70s, IUDs mistakenly got the blame that increased sexual freedom deserved.

The Dalkon Shield disaster continued to cast a pall over all forms of intrauterine devices. IUDs containing copper —introduced during and shortly after the Shield publicity—never became popular in the United States. Total IUD sales declined from 2.2 million to 0.7 million between 1981 and 1988, and manufacturers found that the costs of defending lawsuits were prohibitive. Although copper IUDs were never proved dangerous, most disappeared from the market by the late 1980s. Today, only three IUDs are available in the United States—the Copper-T 380A (also known as the ParaGard), the Progestasert, and a new entry called the Mirena. Effective for a full five years, the Mirena releases a tiny daily amount of levonorgestrel, a hormone similar to the progesterone that helps orchestrate the menstrual cycle.

In other parts of the world, where the negative press about IUDs was never extensive, close to 100 million women now use these devices. In fact, they are the most popular form of birth control in such countries as China, Norway, Finland, and Egypt.

Worldwide studies suggest that:

• IUDs increase a monogamous woman's chances of getting PID only in the first 3 weeks to 3 months after insertion

• IUDs don't affect a woman's chances of having children in the future

• No women have died after an IUD-related miscarriage since 1977

• IUDs have the lowest failure rate of all reversible contraceptives (less than 1 percent for the most commonly used IUD)

• IUD users are more satisfied with their method than are women using any other type of birth control; 98 percent of IUD users report satisfaction, while 92 percent of Pill users and 87 percent of condom users say they are satisfied