The proportion of women who become pregnant unintentionally has dropped significantly since the late 1980s, and the decline is pushing down the rate of abortions.
A study released Saturday by the Alan Guttmacher Institute, a New York-based organization that conducts research on reproductive issues, reported a 16 percent decrease in unintended pregnancies between 1987 and 1994. The change is primarily a result of improved use of contraceptives, according to the study’s author.
But the prevalence of unintended pregnancies nevertheless remains common, with American women reporting that nearly half of pregnancies were unplanned.
The report comes in the midst of renewed attention to the controversy over abortion in this country, as organizations on both sides of the debate mark the 25th anniversary this week of the Supreme Court decision legalizing abortion.
The federal government reported last month that abortion rates declined steadily over the 1990s and had fallen 20 percent since 1980. The abortion rate - the number of abortions per 1,000 women age 15 to 44 - was 20 per 1000 women in 1995, down from 25 in 1980.
Federal researchers and others attributed the lower abortion rate to improved contraceptive use, in combination with other factors, including the aging of the baby boom generation into a less fertile age bracket, changing attitudes toward abortion and diminished access to abortion in some parts of the country.
The new research on unintended pregnancies confirms that abortions are primarily down not because more women are giving birth to babies they would have aborted before, but because women are avoiding pregnancy in the first place.
“Women are using contraception more and more effectively than in the past,” said Stanley K. Henshaw, the Guttmacher researcher who wrote the study.
He said fewer women are taking the risk of having sex without using any contraceptive, and some women are using more effective methods, particularly Norplant implants and Depo Provera injections.
Teenagers, he said, are increasingly using condoms, “probably largely in response to fear of AIDS.”
The study found that from 1987 to 1994 the rate of unintended pregnancy dropped from 54 to 45 pregnancies per 1,000 women of child-bearing age. Unintended pregnancies are most common among younger women, age 18 to 24, and those who are unmarried, low-income and African American or Hispanic.
The study reports that 48 percent of women between 15 and 44 have had at least one unplanned pregnancy. Also, it found that 58 percent of women who had an abortion reported that they had been using a contraceptive during the month they became pregnant.