As oral arguments begin on a Supreme Court case that will shape the future of access to abortion in Texas, a startling truth stands out: No one actually knows how the law affects women's health.

The data on abortion in Texas after the law was passed in 2013 is anecdote-rich and data-poor. With 18 of the state's 41 providers no longer offering abortion care -- and more expected to close if the law is upheld -- researchers who track public health outcomes are still waiting for 2014 data to come out.

“It’s very hard to do this kind of real-time evaluation of the law change, because there’s such a delay” in the data, said Daniel Grossman, a professor in the department of obstetrics and gynecology at the University of California at San Francisco. “The Supreme Court will have decided this case before those stats are available.”

What Grossman and colleagues do know is what happened in the six months after the first provisions of the law began to take effect in 2013 -- the most preliminary snapshot of the aftereffects of the law. There was a 13 percent decline in abortions compared to the same period a year earlier and a small but concerning uptick in the rate of late, second-trimester abortions that Grossman says should be followed closely.

"We know some women are not getting the abortions they want, with a fall in the overall abortion rate," Grossman said. "And beyond that, we know that women are having trouble, having to travel farther, and that’s increasing the cost for women."

As researchers wait for public health data that will give a more complete picture of the law's effect on women and abortion, they have done their best to piece together how the law is affecting women's lives and choices. That has meant interviewing women across Texas about their experiences and performing "secret shopper" studies in which researchers call clinics and try to schedule abortions to gauge wait times.

In a study done by calling clinics each month to try and request an appointment, researchers at the Texas Policy Evaluation Project found an uneven effect. Wait times in some cities were stable -- Houston, for example, and San Antonio. But wait times have fluctuated or increased in some areas, such as Dallas and Fort Worth, and the analysis shows how even a single clinic closing or temporarily not offering abortion care could affect wait times.

In the Dallas-Fort Worth area, average wait times have increased. In June 2015, a high-volume abortion clinic closed, leaving only two facilities in Dallas; wait times jumped to nearly three weeks the following month, as one clinic in the city had to refuse appointments due to high demand.

Researchers have also tried to understand how diminished access affects women's experiences, collecting those in a study published in the journal Contraception.

In the Lower Rio Grande Valley, some women reported traveling long distances, leaving their homes at 3 a.m. to drive four hours and spending $75 on gas to have procedures done. Some women reported spending as much as $200 on hotels because the trip was so long, and one woman reported concerns about cramping and bleeding on a long, uncomfortable car ride home. Other women reported considered obtaining medicine from Mexico that could induce abortion.

The last abortion clinic in south Texas is under attack, legally speaking. (Whitney Leaming/The Washington Post)

One 23-year-old woman from Waco, a mother with two children already, made appointments at two clinics, but then both closed due to the law. She examined the ways she might induce an abortion herself, but was worried about the risks to herself and the baby and decided to carry the child to term because she didn't see other options.

"I was pretty upset, but I just decided that I guess I'll have to just ride it out. I didn't know what else to do, who else to call," she told researchers.

According to the Texas Policy Evaluation Project, at least 100,000 Texas women between the ages of 18 and 49 have attempted to end a pregnancy on their own. What isn't clear is whether that rate has increased after the law was passed, or what other effects the law has had on women's health.

In another study, researchers interviewed 18 women who attempted to induce abortion through methods that ranged from herbal home remedies to medications obtained in Mexico, finding that lack of access, lack of money, a family member's recommendation and stigma were the key reasons women chose to try this route.

One woman told the researchers that she contacted a clinic after her homemade herbal remedy failed. "So when I call to make the appointment, you know, I couldn't," she said. "I think the earliest they saw me was like a month from when I called because they're so busy."

She traveled 150 miles to get an abortion.

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