Abortion surveillance—United States, 1999

Morbidity and Mortality Weekly Report, Nov 29, 2002 by Laurie D. Elam-Evans, Lilo T. Strauss, Joy Herndon, Wilda Y. Parker, Sara Whitehead, Cynthia J. Berg

Abstract

Problem/Condition: CDC began abortion surveillance in 1969 to document the number and characteristics of women obtaining legal induced abortions and to monitor unintended pregnancy.

Reporting Period Covered: This report summarizes and describes data reported to CDC regarding legal induced abortions obtained in the United States in 1999.

Description of System: For each year since 1969, CDC has compiled abortion data by state or area of occurrence. From 1973 through 1997, data were received from or estimated for 52 reporting areas in the United States: 50 states, the District of Columbia, and New York City. Beginning in 1998, CDC compiled abortion data from 48 reporting areas. Alaska, California, New Hampshire, and Oklahoma did not report, and data for these areas were not estimated.

The availability of data regarding the characteristics of women who obtained an abortion in 1999 varied by state and by the number of states reporting each characteristic. The total number of legal induced abortions is reported by state of residence and also by state of occurrence for most areas; characteristics of women obtaining abortions in 1999 are reported by state of occurrence.

Results: A total of 861,789 legal induced abortions were reported to CDC for 1999, representing a 2.5% decrease from the 884,273 legal induced abortions reported by the same 48 reporting areas for 1998. The abortion ratio, defined as the number of abortions per 1,000 live births, was 256 in 1999, compared with 264 reported for 1998; the abortion rate for these 48 reporting areas was 17 per 1,000 women aged 15-44 years for 1999, the same as in 1997 and 1998.

The highest percentages of abortions were reported for women aged <25 years, women who were white, and unmarried women; slightly more than half were obtaining an abortion for the first time. Fifty-eight percent of all abortions for which gestational age was reported were performed at [less than or equal to]8 weeks of gestation, and 88% were performed before 13 weeks. From 1992 (when these data were first collected) through 1999, increases have occurred in the percentage of abortions performed at [less than equal to]6 weeks of gestation. Few abortions were provided after 15 weeks of gestation; 4.3% were obtained at 16-20 weeks and 1.5% were obtained at [greater than or equal to]21 weeks. A total of 27 reporting areas submitted data stating that they performed medical (nonsurgical) procedures (two of these areas categorized medical abortions with "other" procedures), making up <1.0% of all procedures reported from all reporting areas.

In 1998 (for which data have not been published previously and the most recent year for which such data are available), nine women died as a result of complications from known legal induced abortion; no deaths were associated with known illegal abortion.

Interpretation: From 1990 through 1997, the number of legal induced abortions gradually declined. In 1998 and in 1999, the number of abortions continued to decrease when comparing the same 48 reporting areas. In 1998, as in previous years, deaths related to legal induced abortions occurred rarely.

Public Health Action: Abortion surveillance in the United States should continue so that trends and characteristics of women who obtain legal induced abortions can be examined and efforts to prevent unintended pregnancy can be enhanced.

Introduction

CDC began conducting abortion surveillance in 1969 to document the number and characteristics of women obtaining legal induced abortions and to monitor unintended pregnancy. This report is based on abortion data for 1999 provided to CDC's National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), Division of Reproductive Health.

Methods

For 1999, CDC compiled data that were voluntarily provided from 48 reporting areas in the United States: 46 states (excluding Alaska, California, New Hampshire, and Oklahoma), the District of Columbia, and New York City. Legal induced abortion was defined as a procedure, performed by a licensed physician or someone acting under the supervision of a licensed physician, that was intended to terminate a suspected or known intrauterine pregnancy and to produce a nonviable fetus at any gestational age (1,2). The total number of legal induced abortions was available from all reporting areas; however, not all of these areas collected data regarding some or all of the characteristics of women who obtained abortions. Thus, the availability of these data varied by reporting area in 1999.

The majority of reporting areas (45 stares, the District of Columbia, and New York City) collected and reported adequate abortion data (i.e., data categorized in accordance with surveillance variables and with [less than or equal to]15% unknown values) by age of the woman, whereas only 24 states, the District of Columbia, and New York City collected and reported adequate abortion data by Hispanic ethnicity. Therefore, the findings in this report reflect characteristics of women only from reporting areas that submitted adequate data for those characteristics. The percentage data for most state tables include unknown values; unknowns have not been redistributed for the calculation of these percentages. However, percentages based only on known values are included for trend data, out-of-area residents, adolescent ages, and two-characteristics tables.

For the 48 reporting areas, data concerning the number of women obtaining legal induced abortions were provided by the central health agency. * These agencies provided data on numbers of abortions and characteristics of women by the state in which the abortions were performed (i.e., state of occurrence). For most states, only abortion totals were available by state of residence. However, two states, Delaware and Wisconsin, reported characteristics only for women who were residents and who obtained abortions in the stare, but not for women from out of state, and one state (Iowa) provided both numbers and characteristics only for state residents. Two states (Florida and Louisiana) did not report abortion totals by resident status, and two states (Arizona and Massachusetts) provided only the total number of abortions for out-of-state residents without specifying their particular state or area of residence.