Martin Joyce A, Hamilton Brady E, Osterman Michelle J K, Curtin Sally C, Matthews T J
Natl Vital Stat Rep. 2013 Dec 30;62(9):1-68.
This report presents 2012 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal age, live-birth order, race and Hispanic origin, marital status, attendant at birth, method of delivery, period of gestation, birthweight, and plurality. Birth and fertility rates are presented by age, live-birth order, race and Hispanic origin, and marital status. Selected data by mother's state of residence and birth rates by age and race of father also are shown. Trends in fertility patterns and maternal and infant characteristics are described and interpreted.
Descriptive tabulations of data reported on the birth certificates of the 3.95 million births that occurred in 2012 are presented.
A total of 3,952,841 births were registered in the United States in 2012. The general fertility rate declined to 63.0 per 1,000 women aged 15-44. The teen birth rate fell 6%, to 29.4 per 1,000 women. Birth rates declined for women in their twenties and increased for women aged 30-44. The total fertility rate (estimated number of births over a woman's lifetime) declined 1% to 1,880.5 per 1,000 women. The rate of births to unmarried women declined; the percentage of births to unmarried women was essentially stable at 40.7%, but the number of births to unmarried women increased slightly. The cesarean delivery rate was unchanged at 32.8%. The preterm birth rate declined for the sixth straight year to 11.55%; the low birthweight rate declined slightly to 7.99%. The twin birth rate was stable at 33.1 per 1,000 births; the rate of triplet and higher-order multiple births dropped 9% to 124.4 per 100,000 total births.
本报告呈现了2012年美国按多种特征划分的出生数据。数据涵盖产妇年龄、生育顺序、种族和西班牙裔血统、婚姻状况、分娩护理人员、分娩方式、妊娠期、出生体重和多胞胎情况。按年龄、生育顺序、种族和西班牙裔血统以及婚姻状况列出了出生率和生育率。还展示了按母亲居住州划分的选定数据以及按父亲年龄和种族划分的出生率。描述并解读了生育模式以及母婴特征的趋势。
呈现了2012年395万例出生的出生证明上所报告数据的描述性表格。
2012年美国共登记了3952841例出生。总生育率降至每1000名15 - 44岁女性中有63.0例。青少年生育率下降了6%,降至每1000名女性中有29.4例。二十多岁女性的生育率下降,而30 - 44岁女性的生育率上升。总生育率(一名女性一生中预计的出生数)下降了1%,降至每1000名女性中有1880.5例。未婚女性的生育率下降;未婚女性生育的百分比基本稳定在40.7%,但未婚女性的生育数量略有增加。剖宫产率保持不变,为32.8%。早产率连续第六年下降至11.55%;低体重儿出生率略有下降,至7.99%。双胞胎出生率稳定在每1000例出生中有33.1例;三胞胎及以上多胞胎出生率下降了9%,降至每10万例总出生中有124.4例。