Texas has one of the highest teen birth rates in the nation. In 2012, the Texas teen birth rate (the number of live births per 1,000 girls aged fifteen to nineteen completed years) ranked fourth in the nation at 37.8. State teen birth rates remained consistently high even in the face of a steady decline in teen birth rates at the national level from 1990 through 2012. The nation registered a decline of 59 percent whereas the teen birth rate decline in Texas was about 43 percent (Sayegh, Castrucci, Lewis, & Hobbs-Lopez, 2010). The decline in teen births is a desirable outcome necessary for improving adolescent health in Texas, but its sustainability appears to be under threat in the immediate future. According to the traditional viewpoint, the continued high teen birth rate can be attributed to growth in the Hispanic adolescent population in general and to geographical enclaves of high teen fertility in which ethnic characteristics of the population intersect with a number of other sociocultural characteristics (Blake & Bentov, 2001; Sayegh et al., 2010; Scafetta, Hamilton, & Grigolini, 2001). This cultural explanation of high teen fertility has been only partially supported.
The purpose of this study was to examine the geographical variations in the determinants of teen birth rates in Texas. Policy tools necessary to sustain and increase the current declines in teen birth rates in Texas are likely to benefit from analysis of the geographical variations in teen birth rates across counties. In response to a lack of focus on the geography of teen fertility in Texas, this study utilizes an ecological-theory-based aggregate-level approach with the county as the unit of analysis while considering the geographical factors that are likely to influence the variations in county teen birth rates.
Modeling Teen Fertility in Texas Counties
Literature on teen birth levels characterizes a high fertility rate among teens as a sign of social distress (Hawthorn, 1970). This distress is attributed to a number of vulnerabilities that teens face at the individual and group levels. Social vulnerability theory attempts to explain the individual-level differences in terms of the risk of suffering from undesirable social, physical, and health conditions. The theory suggests that, when individuals are exposed to several stress conditions, they become unable to successfully cope with them. The capacity to withstand the effect of stressors tends to vary among people, and the variation in their incapacity to withstand multiple stressors is attributed to the variations in the quantity and quality of resources associated with several demographic and social structural characteristics that moderate the effect of risk exposure (Aday, 1997). The theory also considers the variations in external influences, such as the degree of accessibility and availability of relevant resources that may moderate the risk exposure effects at the individual level. At the aggregate level, both the population and the geographic distribution of sources of individual level vulnerability contribute to individual level outcomes. Aggregate level theories such as social ecological theories have been extensively utilized to explain teen birth rates.
In utilizing the selected variables to account for spatial variations in teen fertility at the aggregate level, the social-ecological approach offers a well-developed theory of social analysis centered on three social constructs (Bell & Shevky, 1955; Brindley & Raine, 1979; Randolph & Tice, 2013). These three social dimensions--socioeconomic status (SES), family status, and ethnic status --were expected to be significantly correlated with teen birth rates. The social area (SA) analysis approach was used extensively to explain county-level teenage birth variations in Texas. Consequently, all variables associated with the three theoretical dimensions and available from our data source were selected for this study. Furthermore, we argued that the presence of major corridors connecting Texas to Mexico would account for partial variations in teen birth rates.
The geographic literature on teen fertility has generally ignored several macro-level issues that are often characterized by the size and characteristics of county regions, rural or urban (Chi, Voss, & Deller, 2006; Hochstrasser, Arthur, & Lewis, 1973; Lawreniuk & Parsons, 2017). One issue is the scarcity of studies examining the linkages between teen births and contextual effects, resulting in misidentification of problems in the current models of fertility. Secondly, aggregate-level studies on teen fertility tend to ignore the presence of public infrastructures such as borders and highways, which affect patterns of migrations and population turnover (Anderson & Gerber, 2008; Chi et al., 2006; Lutz, Testa, & Penn, 2006). At the geographical level, it is hypothesized that internal highway systems that connect Texas to various regions of Mexico will act as a major corridor that significantly increases the movement of goods as well as immigrants from Mexico (Prentice, 2006). The influx of Mexican immigrants into cities such as El Paso, San Antonio, and Houston along highways such as I-10 is likely to be high compared with that along highways distant from Highway I-10 (Rogers, 2006).
One reason for the influx is availability of employment opportunities in these three cities. The other is that many Mexicans who are immigrating to large cities along the I-10 Highway have relatives who are likely to host them among the large Spanish-speaking populations in cities such as San Antonio (Velazquez, 2008; Velazquez, 2013). Although movement of goods from Mexico is likely to increase economic...