Misoprostol Prior to Intrauterine Contraceptive Device Insertion

Intrauterine devices (IUDs) are widely used as reversible contraceptives. Both copper- and levonorgestrel (LNG)-releasing IUDs (LNG-IUDs) are safe,cost-effective in the long term and equally effective compared with tubal sterilization.

In addition, the LNG-IUD (Mirena®) provides non contraceptive benefits, such as treatment for menorrhagia, dysmenorrhea and anemia. The current use of IUDs among reproductive-aged women ranges from 8 to 15% worldwide. Reported complications related to IUD insertion are 8.8% insertion failure, 2.8-11.5% cervical problems, 0.2% cervical perforation, 0.2% syncope and 5.8% expulsion. Insertion failures and cervical problems seem to occur more often among women who have never delivered vaginally.

Cervical stenosis, an immature or small cervix and a significantly ante- or retroverted position of the uterus, has been described as factors associated with a difficult sounding of the cervical canal or even failure to insert the IUD.

Misoprostol is an inexpensive prostaglandin E1-analogue, which is associated with few side effect. More over several have shown the benefit of misoprostol as a cervical ripening agent in non pregnant women. Priming with misoprostol prior to hysteroscopy and dilatation and curettage (D&C) in perimenopausal women resulted in increased cervical dilatation and lower rate of cervical laceration.

The effect of misoprostol on the cellular matrix causes dissolution of collagen fiber increasing the amount of fluid in the stroma and consequentially causes cervical effacement. Fear of pain during insertion, however, might prevent some women from choosing IUD and fears of painful and/or difficult placements may lead them to recommend or counsel women on other, less effective methods.

Women's perception of pain is multifactorial and likely to be influenced by cultural differences and personal experiences; insertion-related pain is therefore difficult to predict. Nevertheless, factors associated with greater pain include nulliparity, not currently breastfeeding and longer time since last pregnancy; of these factors, nulliparity is the strongest predictor of pain.

The proportion of women of reproductive age who are nulliparous is increasing, with women delaying childbirth and having fewer children or choosing to remain childless. The proportion of Caesarean section births has also increased and women who have only ever had a Caesarean section are often viewed as nulliparous with respect to IUD placement. Anticipated pain is often greater than the actual pain experienced, and the majority of nulliparous women experience no more than moderate pain during IUD insertion. However, among nulliparous women there is a subset (about 17%) for whom the insertion of IUD is associated with severe pain.These women need effective pain relief.

For most nulliparous, nulligravid or parous women, IUD insertion can be performed successfully without cervical priming and with a minimum amount of discomfort. Whether selective use of misoprostol has a role in management of pain in certain subsets of women (e.g. nulliparous women and those in whom the insertion is non-routine/difficult) has yet to be adequately studied.