Abortion Surveillance -- United States, 1993 and 1994

Lisa M. Koonin, M.N., M.P.H., Jack C. Smith, M.S., Merrell Ramick, Lilo T. Strauss, M.A., Frederick W. Hopkins, M.D., M.P.H.

Division of Reproductive Health National Center for Chronic Disease Prevention and Health Promotion

Abstract Condition: From 1991 through 1994, the number of legal induced abortions reported to CDC declined each year by less than or equal to 5% from the number reported for the preceding year. Reporting Period Covered: This report summarizes and reviews information reported to CDC regarding legal induced abortions obtained in the United States during 1993 and 1994. This analysis also includes recently reported abortion-related deaths that occurred during 1991. Description of System: For each year since 1969, CDC has compiled abortion data received from 52 reporting areas: 50 states, the District of Columbia, and New York City. Results: In 1993, 1,330,414 legal abortions were reported to CDC, representing a 2.1% decrease from the number reported for 1992; in 1994, 1,267,415 abortions were reported, representing a 4.7% decrease from the number for 1993. In 1993 and 1994, the abortion ratio was 334 and 321 legal induced abortions per 1,000 live births, respectively. In 1993, the abortion rate was 22 per 1,000 women aged 15-44 years; in 1994, this rate declined to 21 per 1,000 women. Women who were undergoing an abortion were more likely to be young, white, and unmarried; most were obtaining an abortion for the first time. More than half of all abortions (52%-54%) were performed at less than or equal to 8 weeks of gestation, and approximately 88% were before 13 weeks. Approximately 15%-16% of abortions were performed at less than or equal to 6 weeks of gestation, 16% were performed at 7 weeks, and 22% at 8 weeks. Younger women (i.e., women aged less than or equal to 19 years) were more likely to obtain abortions later in pregnancy than were older women. In 1991, 12 women died as a result of induced abortion: 11 of these deaths were related to legal abortion and one to illegal abortion. During 1991, the case-fatality rate of legal induced abortion was 0.8 abortion-related deaths per 100,000 legal induced abortions. Interpretation: Since 1990, the number of abortions has declined each year. Since 1987, the abortion-to-live-birth ratio also has declined; in 1994, it was the lowest recorded since 1977. This decrease in the abortion ratio reflected the lower proportion of pregnant women who obtained an induced abortion. As in previous years, deaths related to legal induced abortions occurred rarely (i.e., approximately one death per 100,000 legal induced abortions). Actions Taken: The number and characteristics of women who obtain abortions in the United States should continue to be monitored so that trends in induced abortion can be assessed, efforts to prevent unintended pregnancy can be evaluated, and the preventable causes of morbidity and mortality associated with abortions can be identified and reduced.

INTRODUCTION

In 1969, CDC began abortion surveillance to document the number and characteristics of women obtaining legal induced abortions, monitor unintended pregnancy, and assist efforts to identify and reduce preventable causes of morbidity and mortality associated with abortions. This report is based primarily on abortion data for 1993 and 1994 provided to CDC's National Center for Chronic Disease Prevention and Health Promotion, Division of Reproductive Health.

METHODS

For 1993 and 1994, CDC compiled data from 52 reporting areas: 50 states, the District of Columbia, and New York City. The total number of legal induced abortions was available from all reporting areas; however, not all these areas collected information regarding the characteristics of women who obtained abortions, and the number of states reporting each characteristic differed. States were excluded from the analysis if data regarding a given characteristic were unknown for greater than 15% of women.

For 47 reporting areas, data concerning the number and characteristics of legal induced abortions were provided from the central health agency *; for the other five areas, data concerning the number of abortions were provided from hospitals and other medical facilities. Because information concerning the residence of women who obtained abortions was not available from some states, the procedures were reported by the state in which they were performed. However, two reporting areas (the District of Columbia and Wisconsin) reported abortions by state of residence; occurrence data were unavailable for those areas.

For the analysis of age, women who obtained legal induced abortions were grouped by 5-year age groups. Both ratios (i.e., the number of abortions per 1,000 live births per year) and rates (the number of abortions per 1,000 women per year) are presented by age group in this report. Ratios were calculated by using the number of live births provided by each state's central health agency (except where noted), and rates were calculated by using the number of women reported in special unpublished tabulations provided by the U.S. Bureau of the Census. Because almost all (94%) abortions among women less than 15 years of age are obtained by those aged 13-14 years (1), the population of women aged 13-14 years was used as the denominator for calculating abortion rates for women aged less than 15 years. Rates for women aged greater than or equal to 40 years were based on the number of women aged 40-44 years, whereas rates for all women who obtained abortions were based on the population of women aged 15-44 years.

Race was categorized by either three groups (i.e., a} white, b} black, and c} all other races) or two groups (i.e., a} white and b} black and all other races). "Other" races included Asian/Pacific Islander, Native American/Alaskan Native, and women classified as "other" race.

In 1990, data regarding Hispanic ethnicity were first available on abortion reports submitted by central health agencies to CDC. For the purposes of this surveillance system, Hispanic ethnicity and race were evaluated separately. For the analysis of abortions by race, women of Hispanic ethnicity were categorized as white.

Marital status was reported as either married (which included women who were married or separated) or unmarried (which usually included those who were unmarried, divorced, or widowed). Reporting of marital status differed somewhat by state, particularly for the data used as denominators to calculate abortion ratios by marital status; therefore, abortion ratios by marital status should be interpreted cautiously.

Most areas that reported week of gestation at the time of abortion also reported procedures obtained at less than or equal to 8 weeks of gestation (38 of 41 in 1993 and 38 of 40 in 1994). Gestational age (in weeks) at the time of abortion was reported by most areas from estimates derived from the time elapsed since the woman's last menstrual period. In 10 states in 1993 and 17 states in 1994, gestational age was reported on the basis of the physician's estimate, which could have included information from the clinical examination as well as the time elapsed since the last menstrual period.

CDC periodically has reported information concerning abortion-related deaths; the first year for which such data were available was 1972 (2). Sources for obtaining such information included national and state vital records, maternal mortality review committees, surveys, private citizens, the media, health-care providers, and medical examiner reports. For each reported case, clinical records and autopsy reports were requested and reviewed by a medical epidemiologist to determine the cause of death and verify that the death was abortion-related.

An abortion-related death was defined as a death resulting from a) a direct complication of an abortion, b) an indirect complication caused by the chain of events initiated by the abortion, or c) aggravation of a preexisting condition by the physiologic or psychologic effects of the abortion. Each abortion-related death was then categorized as legal induced, illegal induced, spontaneous, or unknown. Deaths that did not satisfy the criteria of the case definition were classified as not abortion-related. * 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 (3,4).

Before 1978, no gestational age criteria were specified for classifying spontaneous abortion-related deaths. For the reporting year 1978, CDC defined spontaneous abortion as occurring before the completion of the twentieth menstrual week (4). A detailed review of all spontaneous abortion-related deaths during 1978-1989 resulted in the identification of seven deaths that had occurred at greater than or equal to 20 weeks of gestation; these deaths were reclassified as not abortion-related.

Included in this report are a) abortion-related deaths that occurred during 1991 and b) updated totals for spontaneous abortion-related deaths for 1979, 1980, 1982, 1984, 1988, and 1989 (2,5). Case-fatality rates were calculated for legal induced abortion-related deaths per 100,000 legal induced abortions. Trends in case-fatality rates for legal induced abortion for 1972-1991 are reported.

RESULTS

For 1993, 1,330,414 legal induced abortions were reported to CDC, representing a 2.1% decrease from the number reported for 1992 (5); for 1994, 1,267,415 abortions were reported, representing a 4.7% decrease from the number for 1993 (Table_1). In contrast, from 1970 through 1982, the reported number of legal abortions in the United States had increased every year (Table_2), (Figure_1); the largest percentage increase occurred from 1970 to 1971. From 1976 through 1982, the annual increase declined continuously and reached a low of 0.2% for both 1981 and 1982. From 1983 through 1990, the number of abortions increased again, although year-to-year fluctuations were less than or equal to 5%. From 1991 through 1994, the annual number of abortions decreased each year.

The legal induced abortion ratio increased from 1970 to 1980, peaked at 364 abortions per 1,000 live births in 1984, and began to decline steadily after 1987 (to 334 per 1,000 in 1993 and to 321 per 1,000 in 1994) (Figure_1), (Table_2). The legal induced abortion rate increased from five abortions per 1,000 women aged 15-44 years in 1970 to 25 per 1,000 in 1980. From 1981 through 1992, the rate remained stable at 23-24 abortions per 1,000 women, then declined to 22 in 1993 and to 21 in 1994.

In 1993 and 1994, as in previous years, most legal induced abortions were performed in California, Florida, New York City, and Texas; the fewest were performed in Idaho, North Dakota, South Dakota, and Wyoming (Table_3) and (Table_4)) (2,6,7). For women whose state of residence was known, approximately 91% had obtained the abortion within the state in which they resided. In 1994, the percentage of abortions obtained by out-of-state residents ranged from approximately 52%-54% in the District of Columbia to less than 1% in Hawaii. For both 1993 and 1994, nine reporting areas did not provide data concerning abortions obtained by out-of-state residents.

Women aged 20-24 years obtained approximately one third (34% in 1993 and 33% in 1994) of all abortions; women aged less than 15 years obtained less than 1% of all abortions (Table_5) and (Table_6). Abortion ratios were highest for women in the youngest (i.e., less than 15 years and 15-19 years) and the oldest (greater than or equal to 40 years) age groups (Figure_2). The abortion ratio for women aged less than 15 years was 744 abortions per 1,000 live births in 1993 and 704 per 1,000 in 1994. The ratio for women aged 15-19 years (440 and 415 abortions per 1,000 live births in 1993 and 1994, respectively) was similar to that for women aged greater than or equal to 40 years (430 and 412 abortions per 1,000 live births in 1993 and 1994, respectively). The ratio was lowest for women aged 30-34 years (180 and 172 abortions per 1,000 live births in 1993 and 1994, respectively). Among adolescents, the abortion ratio was highest for those aged less than 15 years and lowest for those aged 19 years (Table_7) and (Table_8). Abortion rates were highest for women aged 20-24 years (42 abortions per 1,000 women in 1993 and 39 per 1,000 in 1994) and lowest for women at the reproductive-age extremes (i.e., for women aged less than 15 years, three abortions per 1,000 women in 1993 and two per 1,000 in 1994; for women aged greater than or equal to 40 years, two abortions per 1,000 women in 1993 and 1994) (Table_5) and (Table_6).

For women in most age groups, the abortion ratio increased from 1974 through the early to mid-1980s and declined thereafter, particularly for the youngest and oldest reproductive-aged women (Figure_3). The abortion ratios for women aged less than 15 years have been higher than for the other age groups. In 1994, the abortion ratio decreased for women aged 15-19 years and was the lowest ever recorded for that age group. The abortion ratio for women aged 20-34 years (i.e., the group with the highest fertility rate) has remained stable since the mid-1980s (8).

During 1993 and 1994, approximately 51%-53% of reported legal induced abortions were obtained at less than or equal to 8 weeks of gestation, and about 86% were obtained at less than 13 weeks (Table_9) and (Table_10). In 1993 and 1994, approximately 14%-15% of abortions were performed at less than or equal to 6 weeks of gestation, approximately 16% at 7 weeks, and approximately 21% at 8 weeks (Table_11) and (Table_12). Few abortions were provided after 15 weeks of gestation -- approximately 4% of abortions were obtained at 16-20 weeks, and 1.2%-1.3% were obtained at greater than or equal to 21 weeks (Figure_4).

During both 1993 and 1994, approximately 98% of legal induced abortions were performed by curettage, and less than 1% by intrauterine saline or prostaglandin instillation (Table_13 and Table_14). Hysterectomy and hysterotomy seldom were used; less than 0.01% of abortions were performed by using these methods.

As in previous years, approximately 60% of women who obtained legal induced abortions were white (Table_15) and (Table_16) (2,6). Abortion ratios for black women were 552 abortions per 1,000 live births in 1993 and 538 per 1,000 in 1994; these ratios were almost 2.5 times the ratios for white women (231 abortions per 1,000 live births in 1993 and 217 per 1,000 in 1994). Abortion ratios for women of other races (310 abortions per 1,000 live births in 1993 and 325 per 1,000 in 1994) were approximately 1.3-1.5 times the ratios for white women. In addition, abortion rates for black women (43 and 40 abortions per 1,000 black women in 1993 and 1994, respectively) were approximately three times the rates for white women (15 and 13 abortions per 1,000 white women in 1993 and 1994, respectively).

Twenty-one states in 1993 and 22 states in 1994, the District of Columbia, and New York City * reported information concerning the Hispanic ethnicity of women who obtained legal induced abortions (Table_17) and (Table_18). The percentage of abortions obtained by Hispanic women in these reporting areas ranged from less than 1% in several states to approximately 39%-40% in New Mexico. For Hispanic women in these reporting areas, the abortion ratio was 289 abortions per 1,000 live births in 1993 and 278 per 1,000 in 1994 -- slightly lower than the ratio for non-Hispanics in the same areas (309 and 290 abortions per 1,000 live births in 1993 and 1994, respectively). However, the abortion rate per 1,000 Hispanic women (30 abortions per 1,000 women in 1993 and 29 per 1,000 in 1994) was greater than the rate per 1,000 non-Hispanic women (20 per 1,000 women in 1993 and 18 per 1,000 in 1994).

Seventy-seven to 78 percent of women who obtained abortions were unmarried (Table_19) and (Table_20)). Abortion ratios for unmarried women were approximately nine times the ratios for married women (789 vs. 84 abortions per 1,000 live births in 1993, and 689 vs. 79 in 1994).

Approximately 45%-46% of women who obtained legal induced abortions had had no previous live births, and about 88%-89% had had two or fewer previous live births (Table_21) and (Table_22). The abortion ratio in 1994 was highest for women who had had no previous live births and women who had had two previous live births. The ratio was lowest for women who had had one previous live birth.

In 1993 and 1994, approximately 54% of women who obtained a legal abortion were doing so for the first time. Approximately 17%-18% of women who obtained a legal abortion had had at least two previous legal abortions (Table_23) and (Table_24).

The age distribution of women who obtained a legal abortion differed only slightly by race (Table_25) and (Table_26). However, for women of black or other races, the percentage who were less than 15 years of age, although small (1.2%), was twice the percentage for white women (0.6%). The percentage of women of black or other races who were unmarried (82% in 1993 and 83% in 1994) also was slightly higher than the percentage of white women (77% in 1993 and 78% in 1994). Few differences were found by age and Hispanic ethnicity (Table_27) and (Table_28). Of those women who obtained an abortion, a slightly higher percentage of non-Hispanic women were unmarried in comparison with Hispanic women.

Most women (88%) obtained an abortion during the first 12 weeks of pregnancy; however, adolescents (i.e., women aged less than or equal to 19 years) were more likely than older women to obtain abortions later in pregnancy (Table_29) and (Table_30). The percentage of women who obtained an abortion early in pregnancy (i.e., at less than or equal to 8 weeks of gestation) increased with age. The percentage who obtained an abortion late in pregnancy (at greater than or equal to 16 weeks of gestation) decreased with age for women up to 25-29 years of age, and then remained stable for women in older age groups (Figure_5). Black women were more likely to obtain an abortion later in pregnancy than were white women or women of other races (Table_29) and (Table_30). Although Hispanic women were slightly more likely than non-Hispanic women to have had an abortion at less than or equal to 8 weeks of gestation, the overall differences between Hispanic and non-Hispanic women in the timing of abortions were minimal (Table_29) (Table_30) (Table_31) and (Table_32).

More than 99% of abortions at less than or equal to 12 weeks of gestation were performed by using curettage (primarily suction procedures) (Table_33) and (Table_34). After 12 weeks of gestation, the most frequently used procedure also was curettage, although it usually was reported as dilatation and evacuation (D&E). About the same proportion of intrauterine instillations involved the use of saline or prostaglandin; these procedures were used primarily at greater than or equal to 16 weeks of gestation.

CDC received reports of 32 possible abortion-related deaths for 1991 (i.e., the most recent year for which such data were available). A review of these cases indicated that 18 of the 32 women died from abortion-related causes (Table_35). Eleven of the deaths were associated with legal induced abortion; one death, illegal induced abortion; and six deaths, spontaneous abortion. Possible abortion-related deaths that occurred during 1992-1994 are being investigated.

All deaths reported to CDC for 1972-1990 that had been classified as "spontaneous abortion-related" were reviewed. Seven of these deaths had occurred during 1979-1989 among women at greater than or equal to 20 weeks of gestation. Because these deaths did not meet the criteria for spontaneous abortion-related deaths, they were reclassified as not abortion-related (i.e., pregnancy-related).

The case-fatality rate for legal induced abortion in 1991 was 0.8 deaths per 100,000 legal abortions. During 1980-1991, annual case-fatality rates for legal induced abortion-related deaths were less than or equal to 1.2 deaths per 100,000 legal induced abortions (Table_35) , (Figure_6).

DISCUSSION

In the United States, the annual number of abortions has decreased each year since 1990 (i.e., the year in which the number of abortions was highest) (Table_2)) (2,6,7). In 1994, the national abortion-to-live-birth ratio was the lowest recorded since 1976. The abortion ratio had increased steadily from 1970 through 1980, decreased slightly during 1981-1983, increased to its highest level in 1984, then remained fairly stable until 1987, before beginning to decline (Table_2 , (Figure_1). This decline in the abortion-to-live-birth ratio probably resulted from several complex factors, such as reduced access to abortion services, changes in contraceptive practices, attitudinal changes concerning abortion and/or carrying unplanned pregnancies to term, and the decreased number of unintended pregnancies (9-12).

Induced abortion rates in the United States for 1993-1994 were a) higher than rates reported previously by Australia and Western European countries and b) lower than rates reported by China, Cuba, Eastern European countries, and the New Independent States of the former Soviet Union (13). In addition, for 1994, the legal induced abortion rate in Canada was exactly half the rate in the United States (10.5 abortions per 1,000 women aged 15-44 years vs. 21 per 1,000, respectively), and the abortion-to-live-birth ratio in Canada also was approximately half the ratio in the United States (186 abortions per 1,000 live births vs. 321 per 1,000, respectively) (14). Both abortion rates and birth rates among teenagers have been higher in the United States than in most Western European countries and some Eastern European countries (15).

As in previous years, the abortion ratio in 1993 and 1994 differed substantially by age (2,6). Although the abortion ratio was highest for adolescents, the percentage of legal induced abortions obtained by women aged less than or equal to 19 years decreased steadily from the mid-1980s through 1994 (i.e., from 26% in 1984 to 22% in 1990 and to 20% in 1994) (7,16). Since 1980, the abortion ratio has declined for most age groups -- particularly for women aged less than or equal to 19 years and greater than or equal to 35 years. In 1994, the abortion ratio for women aged 15-19 years was the lowest ratio CDC had ever recorded for that age group. Other studies indicated a decrease in pregnancies among women aged 15-19 years during 1991-1992 (17). Factors such as an overall decrease in the number of abortions, changing access to abortion services (10), and ongoing changes in abortion laws (e.g., parental consent or notification laws and mandatory waiting periods) -- all of which are likely to disproportionately affect adolescents -- could have affected this decline in the abortion ratio (18,19).

In 1993 and 1994, the abortion ratio for black women was more than twice the ratio for white women, and this differential has increased since 1986. In addition, the abortion rate for black women was approximately three times the rate for white women. Race-specific differences in legal induced abortion ratios and rates may reflect differences in factors such as socioeconomic status, contraceptive use, incidence of unintended pregnancies, and access to family planning and contraceptive services.

The abortion-to-live-birth ratio for Hispanic women during 1993 and 1994 was slightly lower than that for non-Hispanic women. Other published reports indicate that pregnant Hispanic women are less likely than pregnant non-Hispanic women to obtain an abortion (20). However, the abortion rate per 1,000 Hispanic women was higher than the rate for non-Hispanic women, a finding that is consistent with several previously published reports (20,21). For women in all age groups, fertility was higher for Hispanic than for non-Hispanic women (8).

For 1994, a total of 34 states, the District of Columbia, and New York City reported Hispanic ethnicity of women who obtained abortions. Because of concerns regarding the completeness of such information in some states, data from only 22 states, the District of Columbia, and New York City were evaluated to determine the number and percentage of abortions obtained by women of Hispanic ethnicity. These geographical areas represented approximately 44% of all reproductive-aged Hispanic women in the United States during 1994 (CDC, unpublished data). One published report of a study that used abortion data obtained from CDC also suggests that the number of Hispanic women who obtain abortions may be underestimated (21). Thus, the number, ratio, and rate of abortions for Hispanic women in this surveillance summary might not be representative of the overall Hispanic population in the United States (i.e., these data might reflect utilization of abortion services only in the states used for this analysis).

The percentage distribution of abortions by gestational age was stable from 1980 through 1994, with slight increases toward the earliest and latest gestational ages (Table_1). Since 1992, most reporting areas have reported gestational age, in weeks of gestation, for abortions performed at less than or equal to 8 weeks (2). These data will assist in monitoring trends in legal abortions as new medical and surgical methods of terminating pregnancy are implemented, because these new methods are primarily for termination of pregnancies at less than or equal to 8 weeks of gestation (22-25).

In this and previous reports, age was inversely associated with timing of abortion (2,26,27). Younger women were more likely to obtain an abortion later in gestation than were older women.

From 1972 to 1994, the percentage of abortions performed by curettage (which includes D&E) increased from 89% to 99% ((Table_1|)), and the percentage of abortions performed by intrauterine instillation and by hysterectomy and hysterotomy declined sharply (from 10% to 0.5% and from 0.6% to less than 0.01%, respectively). From 1974 through 1994, the percentage of second-trimester abortions performed by D&E increased from 31% to 94%; the percentage of second-trimester abortions performed by intrauterine instillation decreased from 57% to 4% (28). The increasing reliance on D&E probably has resulted from the lower risk for complications associated with the procedure (29,30).

Since CDC's surveillance of abortion mortality began in 1972, the annual number of deaths associated with legal induced abortion has decreased by 54% (as of 1991) (31). In 1972, 63 women died as a result of induced abortion. Of those deaths, 24 were associated with legal abortion and 39 with illegal abortion. In 1991, 12 women died as a result of induced abortion: 11 of these deaths were associated with legal abortion and one with illegal abortion. The case-fatality rate decreased approximately 80% between 1972 (4.1 deaths per 100,000 legal induced abortions) and 1991 (0.8 deaths per 100,000 legal induced abortions). These rates, consistent with previously published data for the 1970s and mid-1980s (32-34) indicated that the risk for death from legal induced abortion continues to be extremely low.

The numbers, ratios, and rates of abortion from this analysis are conservative estimates because the numbers of legal abortions reported to CDC for 1993 and 1994 were probably lower than the numbers actually performed. Totals provided by central health agencies are often lower than those obtained by direct surveys of abortion providers (2). For example, the total number of abortions reported to CDC for 1992 * was approximately 11% lower than that reported by The Alan Guttmacher Institute (AGI), a private organization that directly contacts abortion providers to obtain information concerning the number of abortions performed (11). However, since 1987, there has been a decrease in the percentage difference in the number of abortions reported to AGI compared with the number reported to CDC. In addition, not all states collected and/or reported information (e.g., age, race, and gestational age) concerning women who obtained a legal induced abortion during 1993 and 1994; therefore, the numbers, percentages, rates, and ratios derived from this analysis may not be representative of all women who obtained abortions in those years.

Despite these limitations, findings from ongoing national surveillance of legal induced abortion are used for several purposes. First, data from abortion surveillance are used to identify characteristics of women at high risk for unintended pregnancy. Second, ongoing annual surveillance is essential to monitor trends in the number, ratio, and rate of abortions in the United States. Third, statistics on the number of pregnancies ending in abortion are used in conjunction with birth statistics to estimate pregnancy rates (e.g., pregnancy rates among teenagers) (1) and other outcome rates (e.g., the rate of ectopic pregnancies per 1,000 pregnancies). Fourth, abortion and pregnancy rates can be used to evaluate the effectiveness of family planning programs and programs for preventing unintended pregnancy. Fifth, ongoing surveillance provides data for assessing changes in clinical practice patterns related to abortion (e.g., longitudinal changes in the types of procedures and trends in gestational age at the time of abortion). Finally, these data are used as the denominator in calculating abortion morbidity and mortality rates.

Induced abortions are linked usually to unintended pregnancies, which often occur despite use of contraception (19,35,36). In 1995, approximately 31% of live births to women aged 15-44 years were associated with unintended pregnancy (i.e., either mistimed or unwanted at conception) (12). In one study during 1994 and 1995, 58% of women who underwent an abortion reported that they "currently used" contraception during the month of their last menstrual period; however, the use of contraception might have been inconsistent or incorrect (21). Therefore, education regarding improved contraceptive practices, as well as access to and education regarding safe, effective, and low-cost contraception and family planning services, can help reduce the incidence of unintended pregnancy and, therefore, reduce the use of legal induced abortion in the United States (37).

Recently passed welfare-reform legislation -- the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 *

may increase the interest in accurate state-based surveillance of induced abortion. In addition, some states have recently instituted programs that emphasize the prevention of unintended pregnancy, particularly among adolescents. To help guide these efforts, an ongoing, accurate assessment of induced abortion is needed in all states to determine the number and characteristics of women who obtain these procedures.

Additional statistical and epidemiologic information about legal induced abortions is available from CDC's automated Reproductive Health Information System. This system provides information by fax, voice recordings, or mail; telephone (404) 330-1230.

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Includes state health departments and the health departments of New York City and the District of Columbia.
These terms were defined in detail in CDC's abortion surveillance reports for 1977 and 1978 (3,4).
After excluding states for which ethnicity was unknown for greater than 15% of women who obtained an abortion.
The most recent year for which The Alan Guttmacher Institute reported data concerning abortion.

Figure_1