Malpositioned intrauterine contraceptive devices: risk factors, outcomes, and future pregnancies.
OBJECTIVE
To assess possible risk factors, management, and outcomes for women with malpositioned intrauterine contraception devices (IUDs).


METHODS
This retrospective case-control study compared 182 women with malpositioned IUDs shown by ultrasonography at a single institution from 2003 to 2008 with 182 women with properly positioned IUDs. We evaluated whether insertion at 6-9 weeks postpartum, postabortion placement, breastfeeding, type of IUD, pregnancy history, leiomyomas, suspected adenomyosis, and indication for placement were associated with malpositioning. Our study had 70-99% power to detect whether postpartum placement was associated with an odds ratio (OR) of 2-3.


RESULTS
Malpositioned devices were noted on 10.4% of ultrasonography scans among women with IUDs having pelvic ultrasonography for any indication. Most malpositioned devices (73.1%) were noted to be in the lower uterine segment or cervix. Insertion of IUDs at 6-9 weeks postpartum was not associated with malpositioning (OR 1.46, 95% confidence interval [CI] 0.81-2.63). Among other possible risk factors examined, suspected adenomyosis was associated with IUD malpositioning (OR 3.04, 95% CI 1.08-8.52), whereas prior vaginal delivery (OR 0.53 95% CI 0.32-0.87) and private insurance (OR 0.38, 95% CI 0.24-0.59) were protective. Approximately two-thirds (66.5%) of malpositioned devices were removed by health care providers. There were more pregnancies within 2 years among those in the case group than those in the control group (19.2% compared with 10.5%, P=.046). All pregnancies were the result of IUD expulsion or removal, and none occurred with a malpositioned IUD known to be in situ.


CONCLUSIONS
Malpositioning of IUDs does not appear to be associated with insertion at 6-9 weeks postpartum. Women with malpositioned IUDs are more likely to become pregnant because of IUD removal without initiation of another highly effective contraceptive method.
From the Departments of Obstetrics, Gynecology, and Reproductive Biology and Radiology and the Center for Clinical Investigation, Brigham and Women's Hospital, Boston, Massachusetts.
Kari P
KP
Braaten
Carol B
CB
Benson
Rie
R
Maurer
Alisa B
AB
Goldberg
D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007434:Intrauterine Devices / Q000009:adverse effects*; D049590:Postpartum Period; D011247:Pregnancy; D018873:Pregnancy Rate; D012307:Risk Factors; D014463:Ultrasonography