Abortion surveillance - United States, 2010

Abstract

Problem/condition: Since 1969, CDC has conducted abortion surveillance to document the number and characteristics of women obtaining legal induced abortions in the United States.

Reporting period covered: 2010.

Description of system: Each year, CDC requests abortion data from the central health agencies of 52 reporting areas (the 50 states, the District of Columbia, and New York City). The reporting areas provide this information voluntarily. For 2010, data were received from 49 reporting areas. For the purpose of trend analysis, abortion data were evaluated from the 46 areas that reported data every year during 2001-2010. Census and natality data, respectively, were used to calculate abortion rates (number of abortions per 1,000 women) and ratios (number of abortions per 1,000 live births).

Results: A total of 765,651 abortions were reported to CDC for 2010. Of these abortions, 753,065 (98.4%) were from the 46 reporting areas that provided data every year during 2001-2010. Among these same 46 reporting areas, the abortion rate for 2010 was 14.6 abortions per 1,000 women aged 15-44 years, and the abortion ratio was 228 abortions per 1,000 live births. Compared with 2009, the total number and rate of reported abortions for 2010 decreased 3% and reached the lowest levels for the entire period of analysis (2001-2010); the abortion ratio was stable, changing only 0.4%. From 2001 to 2010, the total number, rate, and ratio of reported abortions decreased 9%, 10%, and 8%, respectively. Given the 3% decrease from 2009 to 2010 in the total number and rate of reported abortions, in combination with the 5% decrease that had occurred in the previous year from 2008 to 2009, the overall decrease for both measures was greater during 2006-2010 than during 2001-2005, despite the annual variations that resulted in no net decrease during 2006-2008. In 2010 and throughout the period of analysis, women in their 20s accounted for the majority of abortions and had the highest abortion rates, whereas women in their 30s and older accounted for a much smaller percentage of abortions and had lower abortion rates. In 2010, women aged 20-24 and 25-29 years accounted for 32.9% and 24.5% of all abortions, respectively, and had abortion rates of 26.7 and 20.2 abortions per 1,000 women aged 20-24 and 25-29 years, respectively. In contrast, women aged 30-34, 35-39, and ≥40 years accounted for 15.3%, 8.9%, and 3.4% of all abortions, respectively, and had abortion rates of 13.2, 7.6, and 2.8 abortions per 1,000 women aged 30-34 years, 35-39 years, ≥40 years, respectively. Throughout the period of analysis, abortion rates decreased among women aged 20-24 and 25-29 years, whereas they increased among women aged ≥40 years. In 2010, adolescents aged 15-19 years accounted for 14.6% of all abortions and had an abortion rate of 11.7 abortions per 1,000 adolescents aged 15-19 years. Throughout the period of analysis, the percentage of all abortions accounted for by adolescents and the adolescent abortion rate decreased. In contrast to the percentage distribution of abortions and abortion rates by age, abortion ratios in 2010 and throughout the entire period of analysis were highest among adolescents and lowest among women aged 30-39 years. Abortion ratios decreased from 2001 to 2010 for women in all age groups except for those aged <15 years, for whom they increased. In 2010, most (65.9%) abortions were performed at ≤8 weeks' gestation, and 91.9% were performed at ≤13 weeks' gestation. Few abortions (6.9%) were performed at 14-20 weeks' gestation, and even fewer (1.2%) were performed at ≥21 weeks' gestation. From 2001 to 2010, the percentage of all abortions performed at ≤8 weeks' gestation increased 10%, whereas the percentage performed at >13 weeks' decreased 10%. Moreover, among abortions performed at ≤13 weeks' gestation, the distribution shifted toward earlier gestational ages, with the percentage of these abortions performed at ≤6 weeks' gestation increasing 36%. In 2010, a total of 72.4% of abortions were performed by curettage at ≤13 weeks' gestation, 17.7% were performed by early medical abortion (a nonsurgical abortion at ≤8 weeks' gestation), and 8.3% were performed by curettage at >13 weeks' gestation. Among abortions that were performed at ≤8 weeks' gestation, and thus were eligible for early medical abortion on the basis of gestational age, 26.5% were completed by this method. From 2009 to 2010, the use of early medical abortion increased 13%. Deaths of women associated with complications from abortions for 2010 are being investigated under CDC's Pregnancy Mortality Surveillance System. In 2009, the most recent year for which data were available, eight women were identified to have died as a result of complications from known legal induced abortions. No reported deaths were associated with illegal induced abortions.

Interpretation: Among the 46 areas that reported data every year during 2001-2010, the gradual decrease that had occurred during previous decades in the total number and rate of reported abortions continued through 2005, whereas year-to-year variation from 2006 to 2008 resulted in no net change during this later period. However, the large decreases that occurred both from 2008 to 2009 and from 2009 to 2010 resulted in a greater overall decrease during 2006-2010 as compared with 2001-2005 and the lowest number and rate of reported abortions for the entire period of analysis.

Public health actions: Unintended pregnancy is the major contributor to abortion. Because unintended pregnancies are rare among women who use the most effective methods of reversible contraception, increasing access to and use of these methods can help further reduce the number of abortions performed in the United States. The data in this report can help program planners and policy makers identify groups of women at greatest risk for unintended pregnancy and help guide and evaluate prevention efforts.