The second requires the use in so-called medication abortions of what many doctors called an outdated, less effective and more dangerous drug protocol. Under guidelines based on research studies, the two-drug combination is widely used through the ninth week of pregnancy and accounts for about one in five abortions nationwide.

Under the Texas law, clinics would have to follow, instead, a regime described in the original Food and Drug Administration approval in 2000. Based on initial studies, it required doses three times those of the current protocol and an extra visit to the clinic and was recommended only through seven weeks of pregnancy.

“Politicians are interfering with the personal medical decisions of women who already have the least access to birth control and preventive health care,” said Cecile Richards, president of the Planned Parenthood Federation of America, one of the groups bringing the suit.

Gov. Rick Perry, who has said he hopes to make abortion “a thing of the past,” signed the legislation in July after calling a special session of the Legislature to pass it. The bill came under a national spotlight when Wendy Davis, a Democratic state senator, temporarily derailed passage in the Republican-controlled Legislature with a filibuster.

In a written comment on the lawsuit Friday, Lt. Gov. David Dewhurst attacked abortion rights groups for pursuing “an agenda that disregards the value of human life and accepts subpar medical care for women undergoing a serious surgical procedure.”

Mr. Perry and Republican leaders described the law as important to protect women’s health. Opponents called it an unconstitutional attack on abortion rights and a thinly disguised effort to shutter clinics.

“This law is part of a coordinated national strategy” by anti-abortion groups seeking “to make it impossible to obtain an abortion,” said Jennifer Dalven, director of the Reproductive Freedom Project of the American Civil Liberties Union, another party to the suit along with the Center for Reproductive Rights.

The suit, Planned Parenthood et al. v. Abbott, was filed Friday morning in Federal District Court for the Western District of Texas, in Austin. The goal is to obtain a preliminary injunction to prevent the two measures from taking effect.

Emily Horne, a legislative associate with Texas Right to Life, said that “I believe the law will be found constitutional” and that “over all it’s a great thing for women’s health.”

Similar laws are under litigation in several other states and in most cases have been blocked. In Alabama, Mississippi, North Dakota and Wisconsin, courts have said that requiring physicians to have admitting privileges was an unjustified obstacle to abortion rights.

Courts in North Dakota and Oklahoma have struck down laws imposing the earlier drug protocol for medication abortions, but one remains in effect in Ohio.

Friday’s lawsuit does not challenge two other hotly disputed provisions of the Texas law — a requirement