Two women nearly died after their birth control implants migrated into their abdomens and trapped loops of their bowels, causing life-threatening strangulation. Both patients had used ring-shaped intrauterine devices (IUDs) for over 30 years, significantly longer than the maximum approved duration of up to 10 years.
The women, aged 61 and 73, sought medical attention with symptoms of abdominal pain, nausea, and vomiting. Investigations revealed that their IUDs had eroded through the uterine wall and migrated into the abdominal cavity. Once in the abdomen, the ring-shaped devices created a critical obstruction where a loop of the small intestine became constricted, cutting off blood flow and leading to tissue death. Surgeons were required to remove portions of the bowel in both cases.
While IUDs are generally considered safe and effective, serious complications can occur, particularly when devices are left in place beyond their recommended lifespan or after menopause. As the uterus thins with age and shrinks after menopause, the risk of perforation and migration increases. The ring-shaped IUDs, due to their blunt and rigid nature, tend to migrate more slowly than modern, sharper T-shaped IUDs. However, their inflexibility can cause them to wear through the thinning uterine wall over many years. Once inside the abdominal cavity, their hollow center can trap a loop of intestine.
In contrast, modern T-shaped IUDs are more flexible and less likely to cause this specific type of strangulation complication. If they migrate, they are more prone to directly puncture an organ.
The two reported cases occurred within a six-month period and were documented by surgeons in China. The authors of the report suggested this cluster might indicate a growing concern as global populations age and more women live for decades with retained IUDs. Globally, 40 to 50 million women use ring-shaped IUDs, which are less common in the U.S. due to the potential for later-life complications.
IUDs prevent pregnancy by various mechanisms, including thickening cervical mucus to block sperm and thinning the uterine lining. Copper IUDs also release ions toxic to sperm. Most IUDs are safe for three to 10 years, depending on the type.
Complications with IUDs are rare, affecting less than one to five percent of users. The most common issue is expulsion, where the device slips out of place. Uterine perforation, where the IUD pushes through the uterine wall, occurs in about one to two out of every 1,000 insertions, which is less than 0.2 percent. The risk of ectopic pregnancy, though still extremely low in absolute terms, is slightly higher if pregnancy occurs with an IUD in place.
Both women in the reported cases recovered well following their respective surgeries. The case studies detailed approximately 12 inches and 20 inches of dead bowel being removed from each patient before the healthy ends were reconnected.