Few studies have compared side effects and removal rates of copper and hormonal intrauterine devices (IUDs). We have recently completed a randomised controlled trial of the levonorgestrel intrauterine system (IUS) (Mirena®, Schering, Germany) and the Copper 380® A (IUD) (India) in 160 Muslim women aged 20–35 years attending the Ayat Health Centre in Iran.

Women who presented requesting an IUD for contraception were recruited for the study. After consent was obtained women were randomised (using block randomisation) to either the copper IUD or Mirena. Each woman completed a questionnaire at 1, 3 and 6 months post-insertion to assess side effects.

There was a higher incidence of dysmenorrhea and backache at 3 months with the copper device. Those women with a Mirena had higher rates of spotting and bleeding at 1, 3 and 6 months and higher rates of headache and breast tenderness at 3 and 6 months.

Menstruation and irregular bleeding can interfere with a Muslim woman's ability to pray and attend the mosque. The irregular bleeding experienced by Mirena users may limit the acceptability of the method and should be carefully discussed prior to insertion of the device. Further studies of the acceptability of contraceptives methods in women with different cultural and religious affiliations are advised.