Summary of "Changes in Use of Long-Acting Reversible Contraceptive Methods Among U.S. Women, 2009-2012," Kavanaugh et al., Obstetrics & Gynecology, Oct. 5, 2015.
"It is important to gain a deeper understanding of which groups of women are using LARC methods" to assess how the increase in LARC use is "promising for women who seek to avoid pregnancy"; to examine whether it "disproportionately target[s] minority, poor, and young women"; and to "understand which contraceptive methods women are using at various life stages," according to Guttmacher Institute researchers Megan Kavanaugh, Jenna Jerman and Lawrence Finer.
In this study, the researchers examined "LARC use among females aged 15-44 years using contraception between 2009 and 2012 with a specific focus on associations between race, income level, and age," as well as "associations between their characteristics and their discontinuation of LARC methods resulting from dissatisfaction by type of LARC method."
Methods
The researchers used data from the National Survey of Family Growth, which included 6,428 women interviewed between 2008 and 2010 (labeled "2009") and 5,601 women interviewed between 2011 and 2013 (labeled "2012"). The researchers defined current LARC use as "use of the contraceptive implant or the [intrauterine device] ... during the month of the interview."
In addition to data about LARC use, the researchers collected information about interviewees' "number of male sexual partners in the previous year, whether [they] had ever experienced an [unintended] pregnancy, [their] parity, the number of (additional) births [they] expec[t] in [their] lifetime, and whether [they] had ever stopped using a non-LARC hormonal method as a result of dissatisfaction, because contraceptive users may be more motivated to initiate a LARC method if they disliked a shorter-acting method that they had previously used.”
Findings
The researchers found that among women who used birth control, the proportion of women who used a LARC method increased from 8.5% in 2009 to 11.6% in 2012. They wrote that the overall increase was driven largely by an increase in IUD use, from 7.7% to 10.3% between 2009 and 2012, while "use of the implant remained low (1.3%) and did not change significantly between these two time periods."
The researchers also found significant increases in LARC use from 2009 to 2012 for:
- Hispanic women, from 8.5% to 15.1%;
- Women with private insurance, from 7.1% to 11.1%;
- Women with fewer than two sexual partners in the previous year, 9.2% to 12.4%; and
- Nulliparous women, from 2.1% to 5.9%.
- They found no significant decreases in LARC use across any subgroups.
Meanwhile, according to the researchers, the subgroups of women with the highest LARC use — "greater than 16% of all females using contraception" &mdash in 2012 were:
- Women ages 25 to 34;
- Women in the U.S. who were born in foreign countries;
- Women who lived in the U.S.' western regions;
- Women who identified as "other" when disclosing their religious affiliation;
- Women who had at least one or two prior births; and
- Women who had ever stopped using a non-LARC hormonal method because of dissatisfaction.
In contrast, the subgroups of women with the lowest LARC use — those with "less than 6% of all females using contraception" — in 2012 included:
- Women ages 15 to 19 years old;
- Women ages 40 to 44 years old;
- Nulliparous women; and
- Women who reported that they expected they would have a minimum of three more births.
According to the study, 89% of interviewees who used LARC in 2012 used an IUD, while 11% used an implant. Implant use was more likely with younger women, black women, and women not in the highest income bracket, while IUD use was more common among older women, white women, and women in the highest income bracket.
About three-quarters of IUD users chose a hormonal IUD, while one-quarter used a nonhormonal IUD. According to the researchers, "There were no significant differences in type of IUD use by age or income level." However, they noted that while "fewer than one-fourth of white, black, and females of other or mixed race used the nonhormonal IUD, Hispanic female[s'] use was significantly different than white females' use and was split almost evenly between the hormonal and nonhormonal IUD."
Meanwhile, the researchers found no significant connections between race, income or age with discontinuation among women who "had never used a LARC method" and who discontinued LARC use due to dissatisfaction. However, women with private insurance were less like to discontinue LARC use due to dissatisfaction than women who were uninsured or had other kinds of insurance. There was also a geographic distinction: women living in the South or Midwest were less likely to discontinue LARC use due to dissatisfaction "compared with [women] in the Northeast." Finally, women who had not completed high school discontinued LARC use due to dissatisfaction at higher rates than women with at least a college education.
Discussion
"Women's use of LARC methods has been steadily increasing for approximately a decade; during the most recent time period, use of LARC methods, particularly IUDs, increased almost uniformly across the population of users with significant increases documented among some of the groups of females who are typically at highest risk for unintended pregnancy, namely young adults and [low-income] females," the researchers wrote.
They noted that their findings might "reduce concern about promotion of LARC methods specifically to black females, because there was no continued increase in LARC use among black females between 2009 and 2012," while "use did continue to increase among females of other races and ethnicities." According to the researchers, "black females were less likely than white females to use LARC methods." Meanwhile, "there was no difference in LARC use by poverty status, and there were no differences in discontinuation of LARC methods resulting from dissatisfaction between minority women and non-Hispanic white women."
However, the researchers noted that the lower rates of LARC use among black women could "reflect unequal access to these methods," or "medical mistrust" among black women, who have faced a "legacy of racism and population control as it relates to contraception."
The researchers also noted that the increase in LARC use among nulliparous women and women intending to have children show "that these methods are being used by some women to delay or space pregnancies rather than limit them." However, they wrote that nulliparous women remain less likely than women who have had a child to use LARC, which might suggest that "a lack of awareness of updated clinical guidelines indicating LARC methods as suitable or first-line choices for females at all stages in their reproductive lives."
Meanwhile, the researchers noted that when examined by age group, LARC use was lowest among "the youngest age group," and those in this subset who did use LARC tended to use an implant rather than an IUD. According to the researchers, this trend "may be the result of health care provider perceptions of patient preferences, pain, or pelvic examination avoidance and a higher likelihood of early removal as a result of dissatisfaction." However, the researchers noted that younger women in the study were "not more likely to discontinue these methods as a result of dissatisfaction than older women."
The researchers also added that while their study occurred before the Affordable Care Act's contraceptive coverage rules were implemented, they found that there were "significant increases in LARC use" among full-time employees and women with private coverage. Although women under the ACA are "increasingly paying $0 out of pocket for their contraception ... barriers to obtaining full coverage for methods remain, which may affect LARC use in the future."
According to the researchers, the unintended pregnancy rate in the U.S. during the time of the study period "fell in many states ... with double-digit declines in some states where public health professionals have made proactive efforts to improve access to [LARCs] in particular." The researchers concluded, "By both providing accurate information about methods and prioritizing each individual woman's stated preferences, health care providers can support all females in achieving their childbearing goals."
