Left: IUD with a 200 mm surface area of copper.The distances between the windings allow a quick regeneration of the endometrium at the end of menstruation in these areas.
Right: In contrast, the narrow windings of the copper wire of higher loaded IUDs hamper the regeneration of the endomtrium thus causing additional bleeding and pain, the latter through the increased release of prostaglandines. Lower loaded copper IUDs (left) are useful as “replacement IUDs” in case of unacceptable, additional bleeding and/or pain and for women who are 35 years of age and older. Those IUDs are safer than higher loaded IUDs and equally effective in women of low fertile age-groups or a low frequency of cohabitation.
