NEW YORK — Abortions have declined in states where new laws make it harder to have them — but they’ve also waned in states where abortion rights are protected, an Associated Press survey finds. Nearly everywhere, in red states and blue, abortions are down since 2010.
Explanations vary. Abortion-rights advocates attribute it to expanded access to effective contraceptives and a drop in unintended pregnancies. Some foes of abortion say there has been a shift in societal attitudes, with more choosing to carry their pregnancies to term.
Several of the states that have been most aggressive in passing antiabortion laws — including Indiana, Missouri, Ohio, and Oklahoma — have seen their abortion numbers drop by more than 15 percent since 2010. But more liberal states such as New York, Washington, and Oregon also had declines of that magnitude, even as they maintained unrestricted access to abortion.
Nationwide, the survey showed a decrease in abortions of about 12 percent since 2010.
In New England, Rhode Island and Connecticut have seen the most significant decreases. The number of abortions in Rhode Island between 2010 and 2013 decreased from 4,181 to 3,251. That represents a 22.2 percent drop, the highest in the region. In Connecticut, the number of abortions between 2010 and 2014 decreased from 13,438 to 10,629 — a 20.9 percent drop.
Abortions in Maine between 2010 and 2014 dropped 12.6 percent, while abortions in Vermont and Massachusetts between 2010 and 2013 dropped 8.7 percent and 6.5 percent, respectively. New Hampshire does not compile comprehensive abortion data.
One major factor has been a decline in the teen pregnancy rate, which in 2010 reached its lowest level in decades. There’s been no official update since then, but the teen birth rate has continued to drop, which experts say signals a similar trend for teen pregnancies.
The AP obtained the most recent abortion numbers from the health departments of all 45 states that compile such data on a comprehensive basis. (Other states not compiling such data are California, Maryland, New Jersey, and Wyoming.) With one exception, the data were from either 2013 or 2014 — providing a unique nationwide gauge of abortion trends during a wave of antiabortion laws that gathered strength starting in 2011.
Among the groups most active in promoting the restrictive laws is Americans United for Life. Its president, Charmaine Yoest, suggested that the broad decrease in abortions reflected a change in attitudes among pregnant women.
‘‘There’s an entire generation of women who saw a sonogram as their first baby picture,’’ she said. ‘‘There’s an increased awareness of the humanity of the baby before it is born.’’
Yet five of the six states with the biggest declines — Hawaii at 30 percent, New Mexico at 24 percent, Nevada at 22 percent, and Rhode Island and Connecticut — have passed no recent laws to restrict abortion.
Advocates for abortion rights said the figures demonstrate that restrictive laws are not needed to reduce the number of abortions significantly. That can be achieved, they said, by helping more women obtain affordable, effective contraception, including long-lasting options such as IUDs and hormonal implants.
Judy Tabar, chief executive of Planned Parenthood of Southern New England, said accessible, effective birth control and comprehensive sex education programs are the most important factors in reducing the need for abortion.
She said the drop in abortions in Connecticut, Rhode Island, and elsewhere is due in large part to provisions in the federal Affordable Care Act that enable women to access contraception without a co-payment.
‘‘When birth control is affordable, women are more likely to choose the most effective method,’’ she said, citing IUDs and hormonal implants.
Elizabeth Nash, a state-issues expert for the Guttmacher Institute, a research group that supports abortion rights, said a total of 267 abortion restrictions have been enacted in 31 states since 2011. Among them are measures that ban most abortions after 20 weeks of pregnancy, impose hospital-like physical standards on abortion clinics, and require doctors who perform abortions at clinics to have admitting privileges at nearby hospitals.
While some of the laws have been blocked by lawsuits, most have taken effect, contributing to closure of about 70 abortion clinics in a dozen states since 2010. States with the most closures, according to state officials and advocacy groups, include Texas with 27, Michigan and Arizona with about 12, and Ohio with at least four. Two closed in Virginia, including one that was the state’s busiest.
The only states with significant increases in abortions since 2010 are Republican-led Louisiana and Michigan, which have passed laws intended to restrict abortion. Louisiana — where abortions increased 12 percent between 2010 and 2014 — was recently honored by Americans United for Life as the No. 1 state in taking steps to reduce access to abortion.
In Louisiana and in Michigan, where abortions rose by 18.5 percent, increases were due in part to women coming from states where new restrictions and clinic closures have sharply limited abortion access.