Comprehensive, mainly epidemiological data has helped us to recognize the strongest risk factors of pelvic inflammatory disease during intrauterine contraceptive device use. These are user's exposure to sexually transmitted diseases, young age and insertion of the device. Moreover, parity of the user and type of device may affect the risk of pelvic infection.
PIP: Some people are concerned that IUD use increases the risk of pelvic inflammatory disease (PID), but the extent of the risk and the causal relationship between IUD use and PID are not clear. Two methodological problems with these studies are bias in selecting the comparison group and lack of standard diagnostic criteria for PID. Nonetheless, these studies have identified conditions which increase the risk of PID during IUD use. The woman's or her partner's sexual behavior determines exposure to sexually transmitted diseases (STDs). Regardless of IUD use, women with at least 4 sexual partners face a 3-fold higher risk of PID than those with only 1 partner. Among IUD users, increased coital frequency (5-8 times/month) increase the risk of PID. IUD insertion introduces temporary microbial contamination into the uterus, thereby bringing about a 6-fold increased risk of PID during the first 20 days after insertion. PID rarely occurs in women who have an IUD for more than 5 years, suggesting the need for less frequent replacement of IUDs. Young age alone is a risk factor for PID. For example, women less than 25 years old face a 2-3 fold increased risk of PID compared to women older than 25. Nulliparity appears to be a risk factor for PID, but not a strong factor. The Dalkon Shield IUD has been removed from the market because studies indicated that it significantly increased the risk of PID. Copper-releasing IUDs may have a lower risk of PID than does the Dalkon Shield. Studies show that women with the levonorgestrel-releasing IUD have a significantly lower rate of PID than do those with a copper-releasing IUD. Women in a mutually stable relationship are best suited for IUD use. Physicians should diagnose and treat STDs before insertion of an IUD. IUD replacement should be limited, if possible. Women less than 25 years old, particularly those who are nulliparous, should avoid using an IUD.