IUCD Complications and Lost Threads
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Direct answer
Intrauterine contraceptive device complications include expulsion, perforation, pelvic infection and pregnancy, and a missing thread must be traced before the device is assumed to be in place. Expulsion is most common in the first few months after insertion, especially after a postpartum or postabortal insertion. Any woman with a missing thread needs a pregnancy test and ultrasonography before any further decision.
What you must remember
- Expulsion: Partial or complete; highest after immediate postpartum or postabortal insertion and in nulliparous women.
- Perforation: Penetration of the uterine wall, usually at insertion; the device can migrate into the peritoneal cavity or bowel and then needs laparoscopic removal.
- Pelvic infection: Risk is highest in the first few weeks after insertion, particularly when a sexually transmitted infection is present at insertion.
- Pregnancy with IUCD: Miscarriage and ectopic pregnancy risks are higher than without a device; removal is advised when strings are visible and removal is feasible.
- Heavy bleeding: Copper devices commonly increase menstrual blood loss and cramping, whereas levonorgestrel systems usually reduce it.
- Missing threads: Absent threads mean displacement or expulsion until proven otherwise, and the device is never assumed to be intact.
A stepwise algorithm for missing threads
A missing thread is one of the commonest reasons for IUCD follow-up, and exam scenarios test the order of investigation. The algorithm moves from the least invasive step to the most invasive.
- Exclude pregnancy: Check a pregnancy test first, because pregnancy changes both the urgency and the removal decision.
- Examine the cervix: Use a speculum and gently sweep the endocervical canal, since a thread may be retracted into the canal.
- Ultrasonography: Locate the device in the uterine cavity, cervix or pelvis; transvaginal scanning gives the clearest view.
- Radiograph or CT: If the device is not seen in the uterus, a plain abdominal radiograph can show a copper device because copper is radio-opaque, and CT helps when needed.
- Laparoscopy or hysteroscopy: An intra-abdominal device is removed laparoscopically, and a device embedded in the endometrium is removed hysteroscopically.
Exam answers should confirm that the uterine cavity is empty before concluding perforation, and should reserve laparoscopy for a device confirmed outside the uterus.
Where the exam tries to catch you
IUCD questions usually test the complication, its timing and the sequence of investigation.
- Trap: Assuming the device is still in place because the woman has no symptoms Correct: Expulsion is often painless and unnoticed, so any missing thread requires investigation.
- Trap: Continuing a pregnancy with an IUCD in situ without counselling Correct: The woman needs counselling on miscarriage and ectopic risk, and the device should be removed when strings are visible and removal is feasible.
- Trap: Believing a copper IUCD cannot be seen on X-ray Correct: Copper is radio-opaque, so a plain radiograph can show a displaced copper device.
Frequently asked questions
Why is expulsion more common after postpartum insertion?
The postpartum uterus is larger and still involuting, so it can push out a device more easily. Expulsion is highest after immediate postplacental insertion. Counselling and early follow-up are therefore essential for these women.
Which investigation locates a missing copper IUCD?
Ultrasonography is the first-line investigation for a missing copper IUCD, after pregnancy has been excluded. If the device is not visible in the uterus, a plain abdominal radiograph can show it outside the uterus, because copper is radio-opaque.
Why is pregnancy with an IUCD a concern?
Pregnancy with an intrauterine device carries higher risks of miscarriage, preterm delivery and ectopic pregnancy than pregnancy without one. Ectopic risk matters because the device does not fully prevent tubal implantation. Assessment and removal, when feasible, is the usual approach.
Does a copper IUCD increase menstrual bleeding?
Yes, a copper IUCD commonly increases menstrual blood loss and cramping, especially in the first few months. Levonorgestrel-releasing systems usually reduce bleeding instead. Counselling about these expected effects reduces early removal for side effects.