*Editor's note: This story has been updated with testimony from the first day of trial.

Texas abortion providers were in court Thursday to try to block part of a new state law restricting the most common second-trimester abortion procedure. 

Kicking off a trial expected to last several days, arguments in Whole Woman’s Health, et al. v. Ken Paxton, et al. began at 9 a.m. in the Austin courtroom of U.S. District Judge Lee Yeakel. Lawyers for the state and abortion providers bypassed opening statements and immediately began calling witnesses to testify on the procedure, called dilation and evacuation.

Presiding over a packed courtroom, Yeakel had to pause the proceedings early on to ask a scrum of onlookers, clustered by the courtroom’s entrance, to filter in.

The Texas Tribune thanks its sponsors. Become one.

At issue is part of Senate Bill 8, a state law passed earlier this year, that bans dilation and evacuation abortions — deemed the safest way to terminate a second-trimester pregnancy by medical professionals — unless the fetus is deceased. The lawsuit was filed in July by the Center for Reproductive Rights and Planned Parenthood on behalf of several women’s health providers in the state. Whole Woman's Health is the lead plaintiff.

During the dilation and evacuation procedure, doctors use surgical instruments to grasp and remove pieces of fetal tissue – a process proponents of the law have called inhumane and described as “dismemberment abortion.”

Providers say an effective ban on the method would subject women to medically unnecessary and untested procedures. Doctors would face criminal charges for violating the ban; the only exception would be in cases of medical emergency.

Three doctors who have provided abortions were called to the stand Thursday, all witnesses for the plaintiffs who said requiring fetal demise would add unnecessary risks without providing any benefit to the woman.

"The way I do my procedures currently, and the standard of care is that we don't need to do that," said Bhavik Kumar, medical director of Texas’ Whole Woman’s Health clinics. "So without knowing any additional benefit, especially if the benefits aren't outweighing the risks, it's not something I would recommend to any of my patients."

Besides health risks, the requirement would make getting an abortion “even more burdensome,” Kumar said. Already, “all of my patients face burdens in accessing care” due to existing regulations in the state that reproductive rights’ advocates say are costly and onerous.

The Texas Tribune thanks its sponsors. Become one.

Mark Nichols, an Oregon-based doctor who worked with a local Planned Parenthood affiliate, said dilation and evacuation is a safe procedure but that the demise requirement would lead providers to “essentially experiment” on patients. Three methods for causing fetal demise were discussed Thursday, including digoxin – a drug used to treat certain heart conditions.

Nichols said using digoxin to cause fetal demise early in the second trimester was “uncharted territory.” Other methods for causing demise were also dismissed as risky, unrealistic or unneeded by the witnesses.

In a statement, Attorney General Ken Paxton wrote, “Senate Bill 8 reasonably prohibits live dismemberment of babies still in the womb, a brutal, gruesome and inhumane procedure that involves an abortionist tearing a fully formed child apart limb by limb until its death."

John Seago, legislative director for Texas Right to Life, said the issue "gets on some people's moral radar, even if they like to be called pro-choice ... When they look at the details of the abortion procedure, it doesn't sit well with them."

The ban had an effective date of Sept. 1, but Yeakel blocked its implementation with a temporary restraining order that remains in effect.

SB 8 also prohibits hospitals and clinics from donating aborted fetal tissue to medical researchers and requires health care facilities to bury or cremate fetal remains from abortions, miscarriages and stillbirths.

Reproductive rights groups point to the law's provisions as part of an ongoing strategy to restrict abortion access in the state.

After the SB 8 lawsuit was filed in July, Texas passed three other abortion-related measures during the special legislative session this summer that will increase reporting requirements for abortion complications and require women to buy a supplemental insurance plan if they want coverage for an abortion — called a “rape insurance” policy by opponents.

The Texas Tribune thanks its sponsors. Become one.

The lawsuit over the dilation and evacuation ban is just one of several recent actions abortion rights advocates have taken against Texas.

In June 2016, the U.S. Supreme Court struck down parts of a Texas law that required abortion clinics to meet the same standards as ambulatory surgical centers and required doctors performing the procedure to have admitting privileges at nearby hospitals.

Days after the high court’s decision, the Texas Health and Human Services Commission quietly proposed new rules requiring abortion providers to cremate or bury fetal remains.

And the state tried to kick Planned Parenthood out of Medicaid after outcry over heavily edited videos released in 2015 by an anti-abortion group that appeared to show Planned Parenthood officials in Houston and across the nation discussing how their providers obtain fetal tissue for medical research. Though the videos have been widely debunked, abortion opponents claim they are evidence of Planned Parenthood employees admitting to selling fetal tissue.

A federal judge blocked the fetal remains rule in January of this year, and in February ruled Texas can't kick clinics affiliated with Planned Parenthood out of the state’s Medicaid program. The state is appealing both rulings.

Disclosure: Planned Parenthood has been a financial supporter of The Texas Tribune. A complete list of Tribune donors and sponsors is available here.

Read related Tribune coverage: