"Ask Dr. Cook" is a series of questions and answers regarding endometriosis. The current subject and answer can be found on Current Ask Dr. Cook web page. The questions may represent a summary of questions I have been asked by several different patients. I hope you find this information helpful. If you have a question you would like answered, please Submit A Question.

Is there any connection between IUD use and endometriosis?

Question:
Is there any connection between IUD use and endometriosis? Does the IUD worsen or contribute to it in any way?

Answer:
IUD use may increase the risk of developing endometriosis. We know that heavier menstrual flow is associated with an increased risk of developing endometriosis. Intrauterine devices increase the menstrual flow and thus we presume, retrograde menstruation. Several studies have looked at the possible association between IUD use and endometriosis.

The most recent article was a U.S. study published in 1995. This was a case control study of 3384 women undergoing laparoscopy for tubal sterilization. 126 patients had endometriosis. 504 patients without endometriosis were randomly selected from the group. Long duration of IUD use was associated with an odds ratio of 3.0. Therefore this study demonstrated an increased incidence of endometriosis in patients with history of IUD use.

A Chinese study was published in 1994 which did not support the relationship between IUD use and endometriosis. This was a case control study of 203 women with endometriosis.

A study out of Italy in the same year showed a relative risk of 1.3 for ever users of IUD compared to never users of IUD. A review article was published by Italian authors in 1993. Most of the previous studies reviewed demonstrated either an increased risk of endometriosis with IUD use or no effect. Two previous articles demonstrated a lower risk of endometriosis in previous users of the IUD.

A British study followed 17, 032 women for up to 23 years. This study showed a decrease risk of endometriosis in current users of IUD (relative risk of 0.4) and an increased risk (relative risk of 1.4) in IUD users 49 to 72 months previously compared with never users of IUD

Finally a 1975 article reported a case of endometriosis of the omentum following perforation of the uterus by a Lippes Loop.

In Summary, IUD use probably results in a slight increase risk of endometriosis. This is but one of many potential side effects which should be considered prior to choosing to use the IUD as a method of contraception. Patients with a known history of endometriosis may be better served by another form of contraception.

Updatede October 29, 2005