Two days after an Arizona law placed a ban on abortions after 20 weeks, a three judge panel of the 9th U.S. Circuit Court of Appeals blocked the law, which was set to take effect Aug. 2. Enforcement remains temporarily suspended.

Abortion advocates strongly opposed the initial ruling, claiming that the law interferes with women's health and welfare. Critics said women should be allowed to have an abortion later in their gestation if they discover a complication in the pregnancy. U.S. District Judge James Teilborg upheld the law, ruling that it did not interfere with reproductive rights because a woman may still have an abortion prior to 20 weeks. The law also correctly addressed the ethical problem of an unborn child's ability to experience pain after the 20 week gestation, the judge said.

"Defendants presented uncontradicted and credible evidence to the court that supports this determination," Teilborg wrote in his ruling.

But the 9th Circuit decided the law needs further review--a process that could take months. While the court deliberates, the law will stay off the books.

The law is intended to provide better care for women, and regulate abortion - not block it. Aside from the 20-week ban, the law also requires better regulation of abortion methods that are considered life threatening, an ultrasound for the mother at least 24 hours in advance of an abortion, and consent forms for minors considering abortion. The law does provide an exception for the 20-week ban in cases of medical emergency.

"Though the 9th Circuit's stay is regrettable, all it has done is give itself time to fully consider the case. Once it does, it should see the merits of the district court's decision and uphold Arizona's law," said Steven H. Aden, an attorney for the Alliance Defending Freedom.

Arizona Gov. Jan Brewer signed the measure into law in April, but it has yet to be implemented due to legal disputes. Brewer has had a consistent pro-life stance throughout her political career. She said in a statement after Teilborg's ruling that her heart goes out to any woman who is in circumstances where she has to consider abortion.

The New York-based Center for Reproductive Rights said Teilborg's ruling ran counter to U.S. Supreme Court rulings by effectively banning abortion before viability, not just regulating it. It will force women to wait until an emergency to consider abortion, or it will not give woman enough time to consider whether they want to terminate complicated pregnancies, they say.

Arizona is not the first state to adopt a ban, but it is the first to face a court challenge over the law. North Carolina has long had a 20-week ban. Nebraska in 2010 enacted a ban. Alabama, Idaho, Indiana, Kansas and Oklahoma followed in 2011. Along with Arizona, Georgia and Louisiana approved 20-week bans this year, though Georgia's law doesn't take effect until 2013.

The health risks of having an abortion after 20 weeks significantly increase, including the risk of death during the procedure. Last month a 24-year-old woman died from complications during a second trimester abortion. The biggest concern of the law is to protect women from the serious health issues that arise during abortion procedures.

"The Mother's Health and Safety Act imposes common sense restrictions to prohibit most abortions after 20 weeks of gestation, knowing that health risks to the mother increase with time, and the unborn child will feel pain at this age," Brewer said in a statement issued after the court's decision.

The Associated Press contributed to this report.