Nashville — After struggling to pass a six-week abortion ban earlier this year, Tennessee lawmakers are now considering one of the most restrictive abortion laws in the country: a total ban on the procedure.

On Monday and Tuesday, the state's judiciary committee will hear testimony from more than 20 witnesses and debate an 11-page amendment to its stalled "fetal heartbeat" bill. If the changes are adopted, the legislation will ban abortion once a woman knows she's pregnant.

The committee, which has seven Republicans and two Democrats, is expected to accept the changes. The amended bill would be put up for a vote in January 2020, when the legislature reconvenes.

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This week's summer study comes as states have raced to pass legislation restricting abortion, hoping to challenge Roe v. Wade, the 1973 Supreme Court decision that protects access to the procedure. This year, six states -- Arkansas, Georgia, Kentucky, Louisiana, Mississippi and Ohio -- passed so-called "heartbeat" bills, legislation that bans abortion after cardiac activity can be detected in a fetus. Missouri passed an eight-week ban in May, and Alabama went a step further passing a near-total abortion ban.

Tennessee nearly joined those conservative states with House Bill 77, a "fetal heartbeat" bill that doesn't provide exceptions for victims of rape or incest.

It passed the state's House in March but stalled in the Senate when conservative leaders questioned the efficacy of the bill, said state Senator Kerry Roberts, who serves on the state's judiciary committee, in a telephone interview with CBS News.

"The pro-life people all agreed that they want to see restrictions on abortion, but they started disagreeing on how to do it," Roberts said.

Roberts told CBS News the intention of Tennessee's amended abortion bill isn't to immediately cut off access to the procedure. The point is to provide a legal challenge to Roe v. Wade, Planned Parenthood v. Casey and other Supreme Court precedent.

The original version of House Bill 77 reads similarly to many of the other "fetal heartbeat" bills introduced this year. All face court challenges and nearly all have been blocked from implementation by federal judges. The politicians behind those bills don't consider that a problem, but rather the first step toward a multi-year journey to the Supreme Court.

In Tennessee's Senate, lawmakers, including Roberts, questioned whether "fetal heartbeat" bans were the best vehicle to dismantle the federal protections surrounding abortion. Late in the legislative session, the 11-page amendment was introduced to convert the bill from an effective six-week ban to a near-total abortion ban, providing exceptions only if the procedure would save the mother's life or avert "serious risk of substantial and irreversible impairment of a major bodily function," according to the amendment's text.

"We want a vehicle to lead the Supreme Court to consider, I hope, overturning or at least chipping away at Roe v. Wade," Sen. Roberts said, adding that he doesn't expect the legislation to take effect.

Rather than cutting off access to abortion after cardiac activity is detected, the amendment redefines fetal viability. Federal standards, based on past Supreme Court decisions, consider viability to mean when a fetus can survive on its own outside the womb. In Tennessee, policy makers have proposed that viability is when a pregnancy can be detected.

"They use the findings section to say that a pregnancy is most likely viable at six weeks, but that is entirely different thing than whether the fetus can survive on its own," said Elizabeth Nash, a senior state policy researcher at the Guttmacher Institute, a reproductive rights and health research group, in a telephone interview with CBS News on Friday.

Nash isn't convinced that the amendments would make the bill any more effective at reaching the Supreme Court than any other abortion ban passed this year. However, the lengthy findings section, which accounts for nearly six pages, is a new tactic that could prove more effective. According to Nash, "some courts, including the Supreme Court, have given quite a bit of deference to the findings sections."

While the amendments are expected to be adopted, not all on the judiciary committee support them.

"It's idiotic," said Sen. Katrina Robinson, one of only two Democrats on the state's judiciary committee, in a telephone interview with CBS News on Thursday. "It's completely unconstitutional and our legislator has no right to do this."

Robinson, who has a nursing background and describes herself as "pro-let-me-make-my-own-decisions," expects the Monday and Tuesday sessions to be "long" and "grueling." She's not hopeful about changing any minds.

"These kinds of things, people already have their minds made up when they get there," she said. "The only thing I can try to do is make sure that the information on record is accurate."