Abortion may be legal in America, but US states are throwing up more and more barriers to the practice. So an upcoming decision from the Supreme Court is hotly awaited.

By the end of this month, the nation's highest court is expected to hand down a ruling on an issue that is highly divisive for Americans.

It will concern the state of Texas, specifically, but could reshape how is carried out in the rest of the United States.

As states put up more and more restrictions, the eight members of the court—one of nine seats on the bench is vacant—will either halt this trend or issue a decision that encourages it.

A narrow majority of 56 percent of Americans believe that abortion should be allowed in most or all instances, according to recent study by the Pew Research Center.

Around 41 percent feel the opposite way, with higher numbers among conservative Republicans (68 percent) and white evangelical Christians (69 percent).

The historic 1973 Supreme Court decision known as "Roe v. Wade" that legalized abortion has been the target of repeated attacks by these groups.

But according to the Guttmacher Institute, which is pro-choice, the past five years have accounted for 27 percent of the more than 1,000 restrictions placed on abortion in America in the past four decades.

The pro-choice camp—which advocates letting women choose contraception or elect to end an unwanted pregnancy—is squared off against the so-called pro-life camp which opposes abortion.

'Pro-life' camp strengthened

Since 2010, the latter has been boosted as Republicans scored electoral victories in many US states. Conservatives who want to overturn "Roe v. Wade" go so far as to say the United States has become pro-life.

The restrictions take many forms: bans on the most commonly used medical techniques, long waiting times imposed on women who want abortions, administrative red tape for doctors who perform them, and the granting of legal status to fetuses from the moment of conception.

In many places anti-abortion activists have set up fake clinics—billed as crisis pregnancy centers—that lure in women seeking an abortion, and put them under psychological pressure to forego the procedure.

The bottom line is that at least 57 percent of women of child-bearing age now live in a state considered to be hostile to abortion, says the Guttmacher Institute.

"Since 2011, anti-abortion advocates have pushed for the passage of state-level restrictions on abortion. More recently, they have also begun to propose anti-abortion bills at the state-level that purport to promote women's rights," said Sital Kalantry, a professor at Cornell Law School.

Such is the case in Texas. There, a law passed in 2013 obliges clinics offering abortions to have surgical facilities on par with those of hospitals.

The law, which is said to aim to protect women's health, also obliges doctors who perform abortions to have admitting rights at a local hospital.

'Abortion desert'

These restrictions—which are being weighed by the Supreme Court—have prompted more than half of the abortion clinics in Texas to shut down, advocacy groups say.

"It appears that the current principal political strategy of the anti-abortion activists is to impose such significant burdens on abortion providers that most, if not all of them, have to close their doors," said Michael Dell, a specialist lawyer.

US media have begun to speak of an "abortion desert" in the South, from Florida to New Mexico, and in the Midwest, based on the accounts of hundreds of women forced to travel hundreds of miles to get an abortion.

Besides the distance, these women confront the challenge of having the time and money to make such trips.

Many fear the restrictions will lead women to turn to backstreet abortionists—or perform dangerous self-abortions.

"We do not have research findings that tell us whether the tide of new restrictions is leading more women to turn towards ," said Sarah Roberts, an assistant professor of medicine at the University of California, San Francisco.

But the cost to women of being forced to go ahead with an unwanted pregnancy is well-documented.

"Women unable to have abortions experience more violence, are more likely to be in poverty, and have more physical health consequences than who have abortions," said Roberts.