Professor, Chair, and Associate Dean of Research, College of Public Health, Division of Epidemiology, The Ohio State University, Columbus
SYNOPSIS: Having an intrauterine device (IUD) inserted at four to eight weeks postpartum was associated with higher frequency of uterine perforation, but not higher frequency of expulsion, compared to IUD insertion at nine to 36 weeks postpartum. Overall, perforation and expulsion rates were low.
SOURCE: Ramos-Rivera M, Averbach S, Selvaduray P, et al. Complications after interval postpartum intrauterine device insertion. Am J Obstet Gynecol 2022;226:95.e1-95.e8.
After giving birth, people may desire contraception to avoid having a rapid repeat pregnancy or an unintended pregnancy. Fertility after childbirth can return quickly, and people might resume sexual activity sooner than anticipated. Intrauterine devices (IUDs) and contraceptive implants are the most effective of the reversible methods of contraception. They also have higher continuation rates compared to methods that need more frequent user attention. Two types of IUDs are approved for use in the United States: the copper IUD and the IUD containing levonorgestrel. The Centers for Disease Control and Prevention classifies the use of both IUD types as category 1, meaning without any restrictions for use, for those who are at least four weeks postpartum regardless of their breastfeeding status.1 However, some providers delay placing IUDs in postpartum people because of concerns about the risks of uterine perforation and device expulsion.
Ramos-Rivera and colleagues used electronic medical records from Kaiser Permanente Southern California from 2010 to 2016 to compare the frequency of complications following IUD insertion at four to eight weeks vs. insertion at nine to 36 weeks postpartum. They only included records from adult women who had a singleton birth of at least 24 gestational weeks, without uterine rupture, followed by at least one year of follow-up in the Kaiser system after the interval IUD placement. They had 13,180 records of women who had IUD insertion at four to eight weeks and 11,777 records with IUD placement at nine to 36 weeks. The authors assessed uterine perforation as the primary complication and device expulsion as the secondary outcome. To detect the complications, they pulled the records of the patients in their analysis who had billing data that indicated a complication that might have resulted from an IUD. Then they manually reviewed these records to determine whether the patients were diagnosed with uterine perforation or IUD expulsion. To be included as a uterine perforation in the analysis, the record had to have documentation that laparoscopy or imaging had shown any portion of the IUD beyond the endometrium or that a provider had diagnosed perforation based on sounding to a greater than expected depth.
The authors used logistic regression to compare the frequency of perforations and expulsions that occurred among the earlier vs. the later placement time. They then repeated this after controlling for confounders consisting of race/ethnicity (white, Black, Hispanic, Asian, or multiple), breastfeeding (yes vs. no), type of IUD (copper vs. levonorgestrel), type of provider (attending physician, advanced practice provider, or resident physician), type of delivery (vaginal vs. cesarean), and body mass index (BMI).
Overall, 0.63% of patients had any uterine perforation (n = 157) and 1.1% had any IUD expulsion (n = 273) in the first year after placement. The frequency of perforation was statistically significantly higher in the group with placement at four to eight weeks (0.78%) compared to placement at nine to 36 weeks (0.46%; P < 0.01). This difference remained in the adjusted analysis: The odds of perforation were almost twice as high in the group with earlier rather than later placement (adjusted odds ratio [aOR], 1.92; 95% confidence interval [CI], 1.28-2.89). The analysis of perforation by time showed that the frequency leveled off by 22 weeks to 23 weeks postpartum. In the adjusted analysis, five factors were statistically significantly associated with higher odds of perforation: breastfeeding, levonorgestrel IUD, having at least two births, cesarean delivery, and higher BMI.
In contrast, no difference was found in the frequency of IUD expulsion in the first year in the unadjusted (P = 0.52) or adjusted analysis (P = 0.92). Only two factors were statistically significantly associated with higher odds of expulsion: levonorgestrel IUD and cesarean delivery.
COMMENTARY
Some evidence suggests that short interpregnancy intervals can cause poor birth outcomes.2 Others, though, have argued that the association between short interpregnancy intervals and poor birth outcomes is not causal but instead is the result of confounding; that is, factors that lead people to have a rapid repeat pregnancy also are factors that cause them to be at higher risk of adverse birth outcomes.3 Although the nature of this association remains under debate, we know that rapid repeat births can have negative consequences, such as higher weight gain for the pregnant person, and financial and other stress. Sexual activity often resumes soon after birth. A prospective study of women in a site in Utah found that 43% reported having vaginal sex by six weeks postpartum and almost all (91%) reported this by 12 weeks.4 Postpartum people need support in using contraception to avoid an unwanted, or mistimed, pregnancy. Parents of newborns face competing demands on their time and may have increased difficulty in adhering to methods that require daily or coitally based use. Thus, long-acting methods, including IUDs, can play an important role in preventing rapid repeat pregnancies.
Uterine perforation from IUD insertion, or less often from gradual erosion occurring after IUD insertion, is rare.5 Two older, large studies focused specifically on rates during the first postpartum year. Caliskan et al studied 8,343 women with postpartum IUD insertion in Turkey from 1996 to 2002 and found perforation occurred in 0.22%.6 Perforation was more common when the IUD was inserted at zero to six months postpartum compared to later in the first year. Heinemann studied 61,448 women using postpartum IUD in six European countries from 2006 to 2013 and found perforation occurred in 0.11% to 0.14%.7 Perforation was higher among insertions occurring within 36 weeks postpartum and among breastfeeding people. They found no difference, though, between copper and levonorgestrel IUDs.
The present study supports these earlier studies by also finding low rates of uterine perforation and expulsion after interval postpartum IUD placement. Uterine perforations can lead to bowel or bladder injury, peritonitis, or septicemia; however, long-term complications from perforation seem to be rare.5 Perforation is important, since the process of having the IUD removed carries risk, cost, and discomfort. Furthermore, those with perforation or expulsion may be at risk for unintended pregnancy if they are no longer protected by the IUD.
A main weakness of the analysis is that it relied on a retrospective review of medical records. This could have led to an undercount of the complications. This is a recurring problem with using medical records for research, a purpose for which they are not designed. Billing codes may have been inadequate for finding all of the cases of complications. Incomplete documentation in the medical records also could have led to an undercount of cases of complications. Furthermore, people who sought care for complications outside of the Kaiser Permanente system would have been missed. The authors stated that they addressed this last issue by only including people in the analysis if they had at least one year of follow-up of IUD placement at Kaiser in their medical record. But this assumes that people who failed to attend Kaiser for the year had the same risk of complications as those who continued to attend. This assumption might not be true. For example, patients who experienced a complication after IUD insertion might have decided to seek care elsewhere because they no longer had confidence in their provider’s ability to care for them. In this case, the reported rate of complications would be an underestimation of the true frequency.
It is important to note that this undercounting is unlikely to have affected the primary study finding. The study’s primary finding was that the odds of perforations were almost twice as high following IUD insertion at four to eight weeks compared to insertion at nine to 36 weeks postpartum. This finding is unlikely to be explained by missing or inaccurate data. Providers should counsel postpartum people that the frequency of uterine perforation appears to decrease after 22 weeks postpartum. However, based on the present study and evidence from past research, they can reassure people that the overall rate of perforation and expulsion for IUDs inserted starting at four weeks postpartum appears to be low. Although ultrasounds are not required, or routinely performed, to confirm IUD placement, they could be useful in the case of IUDs inserted at four to eight weeks to verify that perforation did not occur.
REFERENCES
- Curtis KM, Tepper NK, Jatlaoui TC, et al. U.S. medical eligibility criteria for contraceptive use, 2016. MMWR Recomm Rep 2016;65:1-103.
- Ball SJ, Pereira G, Jacoby P, et al. Re-evaluation of link between interpregnancy interval and adverse birth outcomes: Retrospective cohort study matching two intervals per mother. BMJ 2014;349:g4333.
- Shachar BZ, Mayo JA, Lyell DJ, et al. Interpregnancy interval after live birth or pregnancy termination and estimated risk of preterm birth: A retrospective cohort study. BJOG 2016;123:2009-2017.
- Sok C, Sanders JN, Saltzman HM, Turok DK. Sexual behavior, satisfaction, and contraceptive use among postpartum women. J Midwifery Womens Health 2016;61:158-165.
- Rowlands S, Oloto E, Horwell DH. Intrauterine devices and risk of uterine perforation: Current perspectives. Open Access J Contracept 2016;7:19-32.
- Caliskan E, Oztürk N, Dilbaz BO, Dilbaz S. Analysis of risk factors associated with uterine perforation by intrauterine devices. Eur J Contracept Reprod Health Care 2003;8:150-155.
- Heinemann K, Reed S, Moehner S, Minh TD. Risk of uterine perforation with levonorgestrel-releasing and copper intrauterine devices in the European Active Surveillance Study on Intrauterine Devices. Contraception 2015;91:274-279.