The intrauterine device (IUD) is a highly effective, long-acting reversible contraceptive method chosen by millions globally. This small, T-shaped device is inserted into the uterus to prevent pregnancy for several years. Despite its reliability, a persistent fear links IUD use with permanent infertility. This concern largely stems from historical context and misinformation surrounding older devices. Modern IUDs do not compromise a person’s ability to conceive in the future.
Modern IUDs and Fertility Outcomes
Contemporary medical evidence shows that modern IUDs, both hormonal and copper, do not cause tubal factor infertility or compromise future fertility. The myth linking the device to permanent sterility originated primarily from the Dalkon Shield crisis of the 1970s.
This older device had a multifilament string that wicked bacteria from the vagina into the uterus. This design flaw led to severe pelvic infections, causing permanent damage to the fallopian tubes in many users. Modern IUDs are significantly safer, designed with a solid monofilament string that eliminates this infection risk. Studies confirm that the risk of tubal occlusion, a common cause of infertility, is no higher for IUD users than for those who have used no contraception.
Pelvic Inflammatory Disease and the Infection Link
The true, albeit rare, medical risk associated with IUDs is Pelvic Inflammatory Disease (PID), which can cause scarring that leads to tubal factor infertility. PID is an infection of the upper female reproductive tract, including the uterus, fallopian tubes, and ovaries. The infection damages the tissue inside the fallopian tubes, potentially blocking them and preventing future conception.
The highest risk of developing PID occurs in the first 20 days following insertion. This heightened risk is extremely small, reported as less than one percent. The infection is not caused by the device itself, but by introducing pre-existing, undiagnosed sexually transmitted infections (STIs), such as Chlamydia or Gonorrhea, from the cervix into the uterine cavity during insertion.
The insertion process can inadvertently push these bacteria upwards, leading to PID. Therefore, medical guidelines recommend screening for STIs prior to insertion, especially in high-risk individuals. Once the initial three-week window passes, the risk of PID for an IUD user reverts to the same baseline risk as a non-user. PID that occurs later is nearly always linked to a new or untreated STI, not the long-term presence of the IUD.
Distinctions Between Hormonal and Copper IUDs
IUDs are divided into two categories based on their mechanism of action: hormonal and non-hormonal (copper). The copper IUD works primarily by creating a localized inflammatory reaction within the uterus that is toxic to sperm and eggs. The copper ions released act as a spermicide, preventing fertilization.
The hormonal IUD releases a synthetic progestin hormone directly into the uterus. This localized hormone primarily thickens the cervical mucus, blocking sperm entry. It also thins the uterine lining, making it inhospitable for implantation, and may partially suppress ovulation.
Despite their differing mechanisms, both IUD types prevent pregnancy without causing permanent changes to reproductive organs. Research shows that the localized effects of copper inflammation and the progestin hormone do not negatively affect long-term fertility. Neither mechanism is associated with an increased risk of permanent infertility once the device is removed.
Fertility After IUD Removal
The ability to conceive returns rapidly after the removal of either a hormonal or copper IUD. Unlike methods that suppress the entire hormonal axis, the IUD’s effects are highly localized to the uterus. Fertility is restored almost immediately upon removal of a copper IUD, as the device has no systemic hormonal impact.
For those using a hormonal IUD, the return to baseline fertility is also swift, often occurring within the first menstrual cycle after removal. Studies show that the majority of women who have their IUD removed to conceive become pregnant within the first three to six months. This conception rate compares favorably to the rate seen after discontinuing other contraceptive methods, such as oral birth control pills. The duration of IUD use does not impair the speed or likelihood of achieving a future pregnancy.