An intrauterine device (IUD) is a highly effective form of long-acting reversible contraception. This small T-shaped device is inserted into the uterus to prevent pregnancy and is designed to remain effective for several years. IUDs have a set expiration date based on clinical trial data. Once this date passes, their ability to prevent conception begins to diminish. Understanding how each type of device loses its contraceptive power over time explains why an expired IUD may no longer protect against pregnancy.
Types of IUDs and Their Expiration Mechanisms
The two main types of IUDs, hormonal and copper, rely on distinct biological mechanisms to prevent pregnancy, which determines how each device expires. Hormonal IUDs release the synthetic progestin levonorgestrel, and their expiration date is tied to the gradual depletion of this hormone. The progestin works by thickening the cervical mucus, blocking sperm from entering the uterus, and by thinning the uterine lining. Over the device’s approved lifespan, the rate of hormone release steadily decreases. Once the labeled expiration date is reached, the remaining hormone levels may no longer be sufficient to maintain these effects.
Copper IUDs contain no hormones and rely on releasing copper ions into the uterine environment. The copper creates a localized inflammatory reaction that is toxic to sperm, preventing fertilization. The expiration relates to the breakdown and corrosion of the copper wire wrapping, which reduces the surface area available to release these spermicidal ions. If the amount of exposed copper drops below a certain threshold, the device’s spermicidal effect is compromised, increasing the possibility of viable sperm surviving.
Assessing Conception Risk After the Expiration Date
Yes, you can get pregnant with an expired IUD because the active component is depleted or degraded. The loss of protection is gradual, not instantaneous, meaning the risk increases steadily after the expiration date. Some healthcare providers may discuss “extended use” based on studies showing that certain IUDs retain effectiveness beyond their labeled dates. For instance, some copper IUDs approved for ten years have clinical evidence supporting use for up to twelve years.
Relying on extended use requires a personal discussion with a medical professional and should not be assumed. Any use past the manufacturer’s labeled date carries an increased risk of pregnancy. Studies indicate that for women who continue using an IUD past its approved duration, the pregnancy rate can rise significantly. Because the exact level of protection is uncertain after expiration, the device should no longer be considered a reliable form of contraception.
Essential Next Steps and Safety Precautions
If your IUD is past its expiration date, schedule an appointment for its removal or replacement immediately. In the meantime, begin using a reliable barrier method of contraception, such as condoms, to protect against unintended pregnancy. If you have engaged in unprotected intercourse around or after the expiration date, you should take a pregnancy test.
If conception occurs while the IUD is still in place, it requires immediate medical attention. When a pregnancy occurs with an IUD present, there is a heightened risk of complications, including miscarriage. The risk of an ectopic pregnancy is also increased if the IUD fails. An ectopic pregnancy, where a fertilized egg implants outside the uterus (often in the fallopian tube), is a life-threatening condition. Symptoms requiring emergency evaluation include severe abdominal or pelvic pain, unusual vaginal bleeding, or signs of shock like dizziness and fainting.