摘要：Objectives. We assessed whether living in counties with Title X clinics and increased use of long-acting reversible contraception (LARC) in Colorado are associated with decreased risk of adverse birth outcomes. Methods. We linked Title X clinic counties to the Colorado birth data set by using the mother’s county of residence. We compared low birth weight (LBW) and preterm birth (PTB) in 2008 and 2012, in counties with and without Title X clinics. We compared the relationship between LARC use and the incidence of LBW or PTB in 2012 for women living in counties with Title X clinics. Results. For women living in counties with Title X clinics, the odds of PTB were significantly lower in 2012 compared with 2008 (odds ratio = 0.85; 95% confidence interval = 0.81, 0.89; interaction P = .02). For women living in Title X clinic counties in 2012, a higher proportion of LARC use (> 12.4%) was significantly associated with decreased risk of PTB ( P = .02) compared with a low proportion of LARC use (≤ 4.96%). Conclusions. Improved access to family planning services and increased use of LARC are associated with lower risk of PTB. Unintended pregnancy is a significant public health issue in the United States. According to the most recent published estimates, 51% of pregnancies in the United States were unintended, and 60% of unintended pregnancies resulted in a live birth. 1 Unintended pregnancies are associated with increased risk of adverse pregnancy outcomes, such as preterm birth (PTB) and delivery of low–birth weight (LBW) infants. 2–8 In a large systematic review, Shah et al. reported increased odds of PTB (odds ratio [OR] = 1.31; 95% confidence interval [CI] = 1.09, 1.58) and LBW (OR = 1.36; 95% CI = 1.25, 1.48) among unintended pregnancies ending in live birth compared with intended pregnancies. 2 The link between unintended pregnancy and poor birth outcomes is likely multifaceted, and may be associated with maternal socioeconomic risk factors, inadequate prenatal care, and preconceptual and prenatal maternal behavioral risk factors such as smoking and alcohol use. 9–11 As part of the national effort to improve overall public health, increasing the proportion of pregnancies that are intended and decreasing the rates of PTB and LBW deliveries are all objectives of the Healthy People 2020 initiative. 12 In 2008, 37% of live births in Colorado resulted from unintended pregnancies according to the Pregnancy Risk Assessment Monitoring System. 13 To address this issue, the Colorado Initiative to Reduce Unintended Pregnancy (Colorado Initiative) was developed and enacted in 2009 with the generous support of an anonymous donor. 14 As part of the effort, the Colorado Family Planning Initiative was implemented through the Colorado Department of Public Health and Environment. Two of the primary goals of the initiative were (1) increasing the number of women accessing family planning services and (2) increasing the adoption of long-acting reversible contraceptive (LARC) methods such as intrauterine devices and contraceptive implants. 14 Long-acting reversible contraceptive methods are safe and highly effective forms of contraception that have been shown to reduce rates of unintended pregnancy. 15–18 To help achieve these objectives, the Colorado Initiative provided funding to 28 Title X–funded agencies across the state of Colorado from 2009 to 2013, serving 37 of 64 Colorado counties. Those 37 counties were home to 95% of the state’s low-income population (defined as individuals with incomes at or below 150% of the federal poverty level). 14 The locations of Colorado Title X clinics are shown in Figure 1 . This distribution of resources in Colorado is important, in light of the known disparities of unintended pregnancy rates for women on the basis of socioeconomic status, age, race/ethnicity, and level of education. 1 Open in a separate window FIGURE 1— Counties and locations of Title X clinics: Colorado, 2008 and 2012. Source . Colorado Department of Public Health and Environment Family Planning Unit. The funding for the Colorado Initiative specifically supported the provision of intrauterine devices and contraceptive implants to women seeking care at Title X clinics, training for providers and staff on the counseling and provision of LARC methods, and technical assistance to Title X agencies related to increasing the use of these methods. 14 Many of the Title X clinics across the state successfully executed the primary objectives of the Colorado Initiative, resulting in a rise in the total number of clients accessing family planning services per year from 46 201 to 64 148 and the proportion of women choosing LARC methods out of all women using contraception at Title X clinics from 0.8% to 8.6% from 2008 to 2012 (G. Klinger, Colorado Department of Public Health and Environment, e-mail communication, April 1, 2014). Although LARC use is on the rise in the United States, there is little in the published literature demonstrating an association between the use of LARC methods and rates of adverse birth outcomes. 19 Given the scale of the Colorado Initiative, there is a unique opportunity to evaluate this possible association. As a result of improved use of family planning services in general and LARC use in particular, we hypothesized the following: (1) there will be a significant decrease in LBW and PTB in Colorado from 2008 to 2012; (2) for women living in Colorado counties in 2012 compared with 2008, LBW and PTB will differ by whether there is a Title X clinic in that woman’s county of residence; and (3) for women living in Colorado counties with Title X clinics in 2012, there will be a significant inverse association between LARC use at Title X clinics and LBW and PTB.
