The Lower Rio Grande Valley is a fertile floodplain nearly the size of Connecticut on the southernmost tip of Texas and home to a Latino-majority population of 1.3 million. Dubbed the Texas tropics by guidebooks, the Valley is a paradise for bird-watchers and citrus growers — and one of the poorest regions in the country. Its four counties are among the 100 poorest in the United States. Starr County is the third-poorest in the nation, with an annual per capita income of just $7,609; per capita incomes in the other three Valley counties hover around $10,000. An estimated 350,000 Valley residents live in "colonias," rural slums along the U.S.-Mexico border that often lack basic amenities such as paved roads, running water and streetlights. Nearly 40 percent of Hidalgo County residents rely on food stamps.

There were 2,634 abortions, the vast majority performed at clinics, in the Lower Rio Grande Valley in 2011, the last year for which data are available. Demographers estimate that the new law will cause more than 22,000 Texas women to forgo abortions in 2014.

The region is a microcosm of the abortion-rights battles playing out around the nation. Since 2010, anti-abortion activists have stepped up their efforts to restrict abortion access by imposing medically unnecessary regulations on abortion providers. Bills requiring abortion providers to have admitting privileges at local hospitals were introduced in nine states this year and were enacted in four: Alabama, Wisconsin and North Dakota, in addition to Texas. So far, courts in Alabama, Wisconsin and North Dakota have blocked their laws from going into effect, pending court challenges, but the 5th Circuit ruled that Texas' law could go into effect while Planned Parenthood challenges it in court.

According to Roe v. Wade, states may not pass laws preventing women from terminating a pregnancy in the first trimester, and states may pass laws restricting abortion in the second trimester only for the sake of the mother's health.

But the Supreme Court's 1992 ruling in Planned Parenthood v. Casey set new standards. While states could not impose an "undue burden" on a woman seeking to end any pregnancy before the fetus is viable, a 24-hour waiting period, parental consent for minors and "informed consent" were not considered undue burdens. "Informed consent" laws may require abortion seekers to view color photographs of aborted fetuses or to listen to a prepared script linking abortion to breast cancer and suicide — which is not supported by medical literature.

Consequently, over the years, anti-abortion activists have fought to restrict the procedure piecemeal through state-level legislation that makes it more difficult to get an abortion without technically making it illegal.

The anti-abortion legal group Americans United for Life says that several years of "aggressive legislative action" have transformed Texas into one of the most abortion-unfriendly states in the country. In 2000, Texas imposed a parental-notification requirement for minors. Since 2004, Texas has required that abortions after 16 weeks be performed in ambulatory surgical centers, which offer hospital-grade operating rooms suitable for gastric-bypass surgery or back surgery outside a hospital. (Abortion has complication rates comparable to wisdom tooth extraction and other procedures that are routinely performed in medical offices and clinics. Fewer than 0.05 percent result in complications serious enough to require hospitalization.)

Two years later, the state tightened the maternal-health exemption for third-trimester abortions and switched from parental notification for minors to parental consent. In 2011 the state imposed mandatory ultrasounds and a 24-hour waiting period between the scan and the procedure. This July, Gov. Rick Perry signed into law the sweeping House Bill 2, which requires that all abortion providers have admitting privileges at a local hospital, mandates an outdated protocol for medication abortions and bans all abortions after 20 weeks. The law also requires that all abortions be performed in outpatient surgery clinics, but that requirement doesn’t take effect until October 2014.

The legal challenge brought by Planned Parenthood and a coalition of Texas abortion providers focuses on two requirements that came into effect first: local admitting privileges and medication abortions. U.S. District Judge Lee Yeakel ruled that the admitting-privileges requirement lacked any medical justification and granted an injunction to hold that requirement in abeyance until Planned Parenthood's lawsuit could be decided. However, on Oct. 31, a three-judge panel from the 5th Circuit overruled Yeakel and brought H.B. 2's admitting privileges provision into effect immediately. Planned Parenthood asked the Supreme Court to block the law until the 5th Circuit could hear the case this month, but on Nov. 19 the Supreme Court refused to put H.B. 2 on hold while the conservative 5th Circuit makes up its mind.

The Valley used to have two abortion providers — Whole Woman's Health McAllen (WWHM) and Reproductive Services of Harlingen — but now it has none that currently offer abortions, because their doctors lack admitting privileges. (Emergency rooms are required to provide the same care to all patients, regardless of whether their doctors have admitting privileges there. While the doctors at WWHM are applying for privileges at local hospitals, Reproductive Services of Harlingen's physician has already been turned down by all the hospitals in his area.) Even if Planned Parenthood wins its lawsuit, abortions will still have to be performed in ambulatory surgical centers by this time next year, which means that neither clinic can continue to operate in its current facility.