Live Births (Pre 2005)
Data Source: Texas Vital Statistics (VSTAT)
Birth data are derived from a subset of variables collected on the Texas Certificate of Live Birth. Data are presented here from an older birth certificate that has now been discontinued. A new Texas birth certificate was introduced in 2005, which included several changes. The process involved in this revision, as well as details of what was revised, can be found on the CDC website. For some variables, including onset of prenatal care, data from 2005 onward should not be directly compared to data from 2004 and before.
Percentages are the number of births within the indicator divided by all births within the category, excluding cases where the indicator is unknown. For example, the percentage of Low Birth Weight babies is the number of low birth weight babies (birth weight of less than 2,500 grams) divided by the the number of all births within the category with a known birth weight.
Prior to 2004, counts and rates of prematurity may be underestimated due to rounding. In the Texas vital statistics database, gestation periods were measured in whole weeks, so some of those gestation periods that fall between 36 and 37 weeks are rounded up to 37 and not reflected in prematurity counts. For this reason, trends in prematurity rates that span the 2003 - 2004 time periods may show some discontinuity and should be interpreted with care.
Adequacy of prenatal care is measured here with the Kessner Index, which incorporates information from three items recorded on birth certificates: the length of gestation, timing of the first prenatal care visit, and number of visits. The mother of an infant who was carried to term would be classified as having adequate prenatal if she had her first prenatal care visit during the first trimester and had a total of at least 9 prenatal visits. If the gestational age of the infant was less than 36 weeks at birth, then less prenatal visits would be required to be considered adequate as long as they started during the first trimester.