Send to

Choose Destination
See comment in PubMed Commons below
Br J Cancer. 1994 Oct;70(4):672-3.

Intrauterine device use and risk of endometrial cancer.

Author information

  • 1Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.


The relationship between intrauterine device (IUD) use and risk of endometrial cancer has been analysed in a case-control study conducted in Italy between 1983 and 1992, including 453 patients with histologically confirmed endometrial cancer and 1,451 controls admitted for acute, non-gynaecological, non-hormonal, non-neoplastic conditions to the same network of hospitals where cases had been identified. Two (0.4%) cases versus 36 (2.3%) controls reported ever using an IUD. The corresponding multivariate relative risk was 0.4 (95% CI 0.1-1.0). The results of this study and the few published available epidemiological data suggest a protective role of IUD use on endometrial carcinogenesis, but potential selective mechanisms for IUD utilisation (indication bias) should be carefully considered in the interpretation.


In Italy, researchers compared data on 453 patients aged 28-64 years whose histologically confirmed endometrial cancer was diagnosed between 1983 and 1992 with data on 1541 controls aged 27-64 years to examine the association between IUD use and the risk of endometrial cancer. All cases and controls were admitted to the Ospedale Maggiore, to the University Obstetrics and Gynecology Clinics, and to the National Cancer Institute of Milan. Cases were more likely to have no children (22.3% vs. 17.7%; relative risk [RR] = 0.6 [parae vs. nulliparae]), a higher body mass index (or= 25 kg m-2, 56.6% vs. 41.7%; RR = 2), and used estrogen replacement therapy (9.9% vs. 4.7%; RR = 2). Women with endometrial cancer were significantly less likely to have ever used an IUD than controls (0.4% vs. 2.3%; RR = 0.4), suggesting that IUD use had a protective effect against endometrial cancer. Indication bias may explain this inverse association. For example, women with long, heavy menstrual flows or reporting pre-, post-, or inter-menstrual blood spotting may be less likely to be prescribed IUDs. These conditions may be linked to unopposed estrogen endometrial stimulation which increases the risk of endometrial cancer. The low number of IUD users in Italy prevented the researchers from analyzing the role of duration and any other time-related factors. These findings suggest that the IUD protects against endometrial cancer, but one must interpret these findings with caution because of potential indication bias.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for PubMed Central
    Loading ...
    Support Center