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., Period Covered: 2016., 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 2016, data were received from 48 reporting areas. Abortion data provided by these 48 reporting areas for each year during 2007-2016 were used in trend analyses. Census and natality data were used to calculate abortion rates (number of abortions per 1,000 women aged 15-44 years) and ratios (number of abortions per 1,000 live births), respectively., Results: A total of 623,471 abortions for 2016 were reported to CDC from 48 reporting areas. Among these 48 reporting areas, the abortion rate for 2016 was 11.6 abortions per 1,000 women aged 15-44 years, and the abortion ratio was 186 abortions per 1,000 live births. From 2015 to 2016, the total number of reported abortions decreased 2% (from 636,902), the abortion rate decreased 2% (from 11.8 abortions per 1,000 women aged 15-44 years), and the abortion ratio decreased 1% (from 188 abortions per 1,000 live births). From 2007 to 2016, the total number of reported abortions decreased 24% (from 825,240), the abortion rate decreased 26% (from 15.6 abortions per 1,000 women aged 15-44 years), and the abortion ratio decreased 18% (from 226 abortions per 1,000 live births). In 2016, all three measures reached their lowest level for the entire period of analysis (2007-2016). In 2016 and throughout the period of analysis, women in their 20s accounted for the majority of abortions and had the highest abortion rates. In 2016, women aged 20-24 and 25-29 years accounted for 30.0% and 28.5% of all reported abortions, respectively, and had abortion rates of 19.1 and 17.8 abortions per 1,000 women aged 20-24 and 25-29 years, respectively. By contrast, women aged 30-34, 35-39, and ≥40 years accounted for 18.0%, 10.3%, and 3.5% of all reported abortions, respectively, and had abortion rates of 11.6, 6.9, and 2.5 abortions per 1,000 women aged 30-34, 35-39, and ≥40 years, respectively. From 2007 to 2016, the abortion rate decreased among women in all age groups. In 2016, adolescents aged <15 and 15-19 years accounted for 0.3% and 9.4% of all reported abortions, respectively, and had abortion rates of 0.4 and 6.2 abortions per 1,000 adolescents aged <15 and 15-19 years, respectively. From 2007 to 2016, the percentage of abortions accounted for by adolescents aged 15-19 years decreased 43%, and the abortion rate decreased 56%. This decrease in abortion rate was greater than the decreases for women in any older age group. In contrast to the percentage distribution of abortions and abortion rates by age, abortion ratios in 2016 and throughout the entire period of analysis were highest among adolescents and lowest among women aged 25-39 years. Abortion ratios decreased from 2007 to 2016 for women in all age groups. In 2016, almost two-thirds (65.5%) of abortions were performed at ≤8 weeks' gestation, and nearly all (91.0%) were performed at ≤13 weeks' gestation. Fewer abortions were performed between 14 and 20 weeks' gestation (7.7%) or at ≥21 weeks' gestation (1.2%). During 2007-2016, the percentage of abortions performed at >13 weeks' gestation remained consistently low (8.2%-9.0%). Among abortions performed at ≤13 weeks' gestation, the percentage distributions of abortions by gestational age were highest among those performed at ≤6 weeks' gestation (35.0%-38.4%). In 2016, 27.9% of all abortions were performed by early medical abortion (a nonsurgical abortion at ≤8 weeks' gestation), 59.9% were performed by surgical abortion at ≤13 weeks' gestation, 8.8% were performed by surgical abortion at >13 weeks' gestation, and 3.4% were performed by medical abortion at >8 weeks' gestation; all other methods were uncommon (0.1%). Among those that were eligible for early medical abortion on the basis of gestational age (i.e., performed at ≤8 weeks' gestation), 41.9% were completed by this method. In 2016, women with one or more previous live births accounted for 59.0% of abortions, and women with no previous live births accounted for 41.0%. Women with one or more previous induced abortions accounted for 43.1% of abortions, and women with no previous abortions accounted for 56.9%. Deaths of women associated with complications from abortion are assessed as part of CDC's Pregnancy Mortality Surveillance System. In 2015, the most recent year for which data were reviewed for abortion-related deaths, two women were identified to have died as a result of complications from legal induced abortion and for one additional death, it was unknown whether the abortion was induced or spontaneous., Interpretation: Among the 48 areas that reported data every year during 2007-2016, decreases in the total number, rate, and ratio of reported abortions resulted in historic lows for the period of analysis for all three measures of abortion., Public Health Action: The data in this report can help program planners and policymakers identify groups of women with the highest rates of abortion. Unintended pregnancy is the major contributor to induced abortion. Increasing access to and use of effective contraception can reduce unintended pregnancies and further reduce the number of abortions performed in the United States., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.