Births: final data for 2013.
Level 4 - case-series / case-control
Level 4 by design analogy (cross-sectional descriptive surveillance of national birth registry data).
What was done
Descriptive analysis and tabulation of birth certificate data for all registered live births occurring in the United States during 2013. Variables evaluated included maternal age, live-birth order, race and Hispanic origin, marital status, state of residence, attendant at birth, delivery method, gestational age, birthweight, plurality, and paternal age and race.
What was found
In 2013, a total of 3,932,181 births were registered in the US (down <1% from 2012). The general fertility rate declined to 62.5 per 1,000 women aged 15–44, and the total fertility rate dropped 1% to 1,857.5 per 1,000 women. Teen birth rates (aged 15–19) dropped 10% to 26.5 per 1,000. Birth rates declined for women in their 20s but rose for most age groups aged 30 and older. Unmarried childbearing measures declined. The cesarean delivery rate fell to 32.7%. Preterm births dropped for the seventh consecutive year to 11.39%, while the low birthweight rate remained essentially unchanged at 8.02%. The twin birth rate increased 2% to 33.7 per 1,000 births, whereas triplet and higher-order multiples dropped 4% to 119.5 per 100,000 births.
Why it matters
Provides official population-level benchmarks for US reproductive and perinatal outcomes in 2013, capturing ongoing demographic shifts toward older maternal age and continued declines in teen pregnancy and preterm deliveries.
Limits
As an observational summary of birth certificate records, data quality depends on the accuracy and completeness of vital statistics reporting across jurisdictions. The cross-sectional, descriptive design cannot identify causal drivers of the observed trends, and unmeasured clinical or socioeconomic factors are not accounted for in standard birth records.
Cited by
- supports Placentas are discarded after delivery roughly 3.9 million times per year in the United States alone.