Ultrasound-guided hysteroscopy to remove a levonorgestrel intrauterine system in early pregnancy

Background: Correctly placed levonorgestrel-releasing intrauterine systems (LNG-IUSs) are rarely associated with intrauterine pregnancy when pregnancy occurs. LNG-IUS retrieval, termination of pregnancy and conservative management if retracted strings prevent ready removal are the usual clinical options given to women. The conservative course raises concerns about teratogenesis related to high local progestin exposure for the developing fetus.

Study design: This case report describes combined saline hysteroscopy and ultrasound to retrieve an LNG-IUS at less than 9 weeks of gestational age. A systematic review of the literature was performed to identify similar case reports by contacting the manufacturer and searching Pubmed from 1900 through November 2011 using the terms ((levonorgestrel AND intrauterine) OR mirena) AND (pregnan* OR fetal OR fetus OR teratogen*) NOT (menorrhagia OR hyperplas* OR ectopic OR malig* OR cancer).

Results: We identified 37 cases of LNG-IUS pregnancy exposures in the absence of spontaneous expulsion or myometrial or intraperitoneal placement of LNG-IUS. Given the presence of two congenital anomalies reported in the group, the anomaly rate is 5.4%, 95% confidence interval 0% to 11.5%.

Conclusions: Intrauterine LNG-IUS exposure is associated with a low frequency of congenital anomalies. Combining hysteroscopy with ultrasound facilitates surgically precise LNG-IUS removal despite retracted strings.