The IUD string check: Benefit or burden?

Author and Disclosure Information

Routine office visits and patient self-checks for IUD strings are unsupported by data and are costly—it is time to discontinue them



CASE A patient experiences unnessary inconvenience, distress, and cost following IUD placement

Ms. J had a levonorgestrel intrauterine device (IUD) placed at her postpartum visit. Her physician asked her to return for a string check in 4 to 6 weeks. She was dismayed at the prospect of re-presenting for care, as she is losing the Medicaid coverage that paid for her pregnancy care. One month later, she arranged for a babysitter so she could obtain the recommended string check. The physician told her the strings seemed longer than expected and ordered ultrasonography. Ms. J is distressed because of the mounting cost of care but is anxious to ensure that the IUD will prevent future pregnancy.

Should the routine IUD string check be reconsidered?

The string check dissension

Intrauterine devices offer reliable contraception with a high rate of satisfaction and a remarkably low rate of complications.1-3 With the increased uptake of IUDs, the value of “string checks” is being debated, with myriad responses from professional groups, manufacturers, and individual clinicians. For many practicing ObGyns, the question remains: Should patients be counseled about presenting for or doing their own IUD string checks?

Indeed, all IUD manufacturers recommend monthly self-examination to evaluate string presence.4-8 Manufacturers’ websites prominently display this information in material directed toward current or potential users, so many patients may be familiar already with this recommendation before their clinician visit. Yet, the Centers for Disease Control and Prevention state that no routine follow-up or monitoring is needed.9

In our case scenario, follow-up is clearly burdensome and ultimately costly. Instead, clinicians can advise patients to return with rare but important to recognize complications (such as perforation, expulsion, infection), adverse effects, or desire for change. While no data are available to support in-office or at-home string checks, data do show that women reliably present when intervention is needed.

Here, we explore 5 questions relevant to IUD string checks and discuss why it is time to rethink this practice habit.

What is the purpose of a string check?

String checks serve as a surrogate for assessing an IUD’s position and function. A string check can be performed by a clinician, who observes the IUD strings on speculum exam or palpates the strings on bimanual exam, or by the patient doing a self-exam. A positive string check purportedly assures both the IUD user and the health care provider that an IUD remains in a fundal, intrauterine position, thus providing an ongoing reliable contraceptive effect.

However, string check reliability in detecting contraceptive effectiveness is uncertain. Strings that subjectively feel or appear longer than anticipated can lead to unnecessary additional evaluation and emotional distress: These are harms. By contrast, when an expulsion occurs, it often is a partial expulsion or displacement, with unclear effect on patient or physician perception of the strings on examination. One retrospective review identified women with a history of IUD placement and a positive pregnancy test; those with an intrauterine pregnancy (74%) frequently also had a malpositioned IUD (55%) and rarely identifiable string issues (16%).10 Before asking patients and clinicians to use resources for performing string evaluations, the association between this action and outcomes of interest must be elucidated.

If not for assessing risk of expulsion, IUD follow-up allows the clinician to evaluate for other complications or adverse effects and to address patient concerns. This practice often is performed when the patient is starting a new medication or medical intervention. However, a systematic review involving 4 studies of IUD follow-up visits or phone calls after contraceptive initiation generated limited data, with no notable impact on contraceptive continuation or indicated use.11

Most important, data show that patients present to their clinician when issues arise with IUD use. One prospective study of 280 women compared multiple follow-up visits with a single 6-week follow-up visit after IUD placement; 10 expulsions were identified, and 8 of these were noted at unscheduled visits when patients presented with symptoms.12 This study suggests that there is little benefit in scheduled follow-up or set self-checks.

Furthermore, in a study in Finland of more than 17,000 IUD users, the rare participants who became pregnant during IUD use promptly presented for care because of a change in menses, pain, or symptoms of pregnancy.13 While IUDs are touted as user independent, this overlooks the reality: Data show that device failure, although rare, is rapidly and appropriately addressed by the user.

Continue to: Does the risk of IUD expulsion warrant string checks?...


Next Article: