McALLEN, Texas — The colorful murals outside the storefront clinic a few miles from the Mexican border celebrated “dignity, empowerment, compassion, justice.” Inside, there was a reminder posted on the wall for anyone who had begun to doubt it: “Abortion Is Legal in Texas!”

A 28-year-old woman peered anxiously at the sign and gently caressed a necklace with an image of St. Jude, the patron saint of lost causes and hopeless situations.

Her situation indeed felt difficult: three young children at home, a husband in prison, an unfinished college education. Another baby, she told herself, would send her struggling family straight over the edge. “I never thought I would be here,” said the woman, who before coming in had driven past a few anti-abortion protesters demonstrating outside and had to stop her car to throw up. “It took me a lot to be here today. I have not been able to sleep for a week, running this day over and over in my head. I just know I can’t have this baby.”

The reminder that some early-term abortions remain legal in Texas comes as the state’s remaining clinics navigate a recent law that threatens punitive lawsuits for anyone aiding abortions beyond about six weeks of pregnancy. A draft opinion from the U.S. Supreme Court that was leaked to reporters this week threatens to trigger an even more far-reaching law — passed by Texas lawmakers last year in anticipation of a day Roe v. Wade is overturned — that would subject abortion providers to potential sentences of life in prison or $100,000 fines.

Clinics like Whole Woman’s Health, the only abortion facility serving a population of a million people in the Rio Grande Valley, have been filled in recent weeks with women like the 28-year-old who are urgently trying to reconstruct their menstrual timetables and undergo ultrasound examinations to make sure they fall inside the six-week window.

By and large, the women at this clinic, located in the heavily Latino city of McAllen, about 10 miles north of the U.S.-Mexico border, reflect some of those across the country who are likely to face the most formidable consequences from new state limits on abortion.

Data shows that poor or low-income women make up 75 percent of all those seeking to end their pregnancies. About 60 percent of those seeking legal abortions are Black or Hispanic, federal data shows, and analysts say it is these women who most acutely face the dilemma of balancing low-paying jobs with unpredictable schedules, high child care costs and the hope of attending college part-time with the reality of another child to support.

While some clinics in Mexico may continue to offer help with abortions, many women living in McAllen and surrounding U.S. communities could otherwise face a drive of more than 800 miles to reach the nearest legal abortion clinic in Las Cruces, N.M., should Whole Woman’s Health and other Texas facilities be forced to close.

The young woman sitting in the waiting room, who like others interviewed for this article did not want to be named in order to protect her privacy, said she could expect judgment and little help from her husband, now doing time for murder, and from most members of her family, if they found out she had aborted a pregnancy.

Most of those interviewed said that the culture in the Rio Grande Valley, predominantly Mexican American and heavily Catholic, forces women considering an abortion to do so alone and remain forever silent about it afterward.

“You know, in our culture, being Mexican, it is not really supported,” the woman said. “You feel like you can’t tell anyone.”

In the waiting room, where most of the women avoided looking at one another, she fretted. “What must they think of me?” she murmured. Then she let out a nervous giggle, remembering that they were probably all there for the same reason.

Her three children, ages 11, 9 and 7, are all in school now, but she is a year away from getting the degree in criminal justice she needs to get a job that pays better than her clerical work.

On the one hand, she said, “I just want to continue my career,” and on the other, “I need to take care of my babies, the ones I have now.”

Then she missed a period, despite using birth control, and a situation that she said previously seemed hard now felt impossible.

She said she had initially worried about the Texas law that took effect Sept. 1 — a model now being adopted in other conservative states — that deputizes civilians to file lawsuits against any doctor who performs an abortion after fetal cardiac activity, about six weeks of pregnancy. Doctors measure the start of pregnancy from the first day of a woman’s last menstrual period, which is usually two weeks before a fetus is conceived. As a result, many women barely know they are pregnant by the time they are up against the six-week limit.

Though women are not supposed to be targeted under the law, she had read the recent news coverage about a woman who was accused of murder in nearby Starr County after having what was described as a “self-induced” abortion after six weeks. The woman was later released after a national outcry.

So when the doctor on duty at Whole Woman’s Health, Dr. Blair Cushing, informed the 28-year-old woman that she was under the law’s limit, at five weeks of pregnancy, her heart slowed down. “I didn’t want to be arrested too,” she said.

Dr. Cushing instructed her to take a single dose of mifepristone, the size of an aspirin, during an office visit the next day and a second dose, four tablets of misoprostol, within 48 hours.

The doctor read out a list of risks associated with medication abortion, which can include excessive bleeding, potential for retained tissue inside the uterus, infection and an allergic reaction to the medication.

Under state law, the doctor was required to show the patient her ultrasound scan, which at such an early stage of pregnancy usually shows little more than the gestational sac, the bag of fluid where the embryo is growing.

The law also requires doctors to talk to patients about the possibility of waning fertility and an increased risk of breast cancer for those who have abortions, a risk discounted by many experts who have studied it. Dr. Cushing said the materials she was required to discuss with her patients were intended “to try to mislead and scare women.”

The abortion itself, the doctor told the woman, would feel like a heavy menstrual period. “She told me, ‘You are early, there is really nothing there,’” the woman recalled after the initial consultation. “I feel OK. I’m trying to get through it. This is the right decision for me now.”

Not everyone follows through. Dr. Cushing and other medical providers said they have seen instances of women changing their minds after visiting the clinic.

“We understand that this is a very personal decision,” Dr. Cushing said. “That’s exactly what I tell patients. I want you to feel very confident about your decision. This isn’t something that you can take back.”

Another health worker, who began working at the clinic three months ago, said she sometimes shared with her patients that she had an abortion at the age of 18 when she was 10 weeks pregnant. Like many of her patients now, she said, she feared that a pregnancy could hurt her chances of getting a better job.

She had also worried about being ostracized by her family and neighbors if anyone found out, she said.

“Down here, we are raised Catholics and Christians and we don’t talk about sex in general,” she said. “We don’t talk about it because it’s taboo here.”

Across the Rio Grande Valley, churches talk about alternatives to abortion and often pledge to help women who face challenging pregnancies.

The Rev. Derlis Garcia, director of the Pro-Life Office with the Catholic Diocese of Brownsville, which includes McAllen, said the priority of the church was to protect the life of the unborn. Many of the region’s churches and centers open their doors to women who may be considering an abortion and offer counseling and support for those who have terminated their pregnancies.

“As Catholics in the Rio Grande Valley, we have deep concern for the most vulnerable, the baby in her womb,” Father Garcia said. “We care deeply as well about mothers in difficult circumstances.”

Since passage of the abortion law in September, the number of people seeking consultation at the clinic — on an average day, about 20 to 40 — has not shrunk, Dr. Cushing said. But the number of patients being turned away has increased, about 40 percent of those who come in. Many arrive past the six-week mark.

A 25-year-old woman who arrived at the clinic said she was worried she might be past that cutoff. The woman has a 1-year-old and 5-year-old, works at a low-wage job during the day and attends classes online. There was no room in that schedule for another pregnancy, she said. “Watching them grow up, balancing school and like balancing work and with everything going on, I think a third one is going to be too much,” she said.

Because she tends to have irregular periods, she explained, she took three pregnancy tests “after my body felt different” three weeks earlier. The first came out negative. The next two did not.

She sat quietly waiting her turn at the clinic, its walls decorated with portraits and quotes of inspiring women, including Michelle Obama, the former first lady, and Selena Quintanilla, the Tejano singer. On the wall of another room was a large quote from Jessica Farrar, a former Texas state representative: “We will not stop standing, we will not stop fighting.”

Alisha Moreno, a medical assistant, sat across from the woman and walked her through her next two days under the abortion pill regimen.

“That first pill stops the growth of the pregnancy,” Ms. Moreno told her.

She would be given ibuprofen and medication to treat nausea.

“After that, between an hour to two hours, you are going to start expelling the pregnancy out.” she went on. “So you’re going to be experiencing cramping, pain and passing of blood clots, maybe the size of your fists, or maybe less, just because you are early in your pregnancy.”

The woman nodded, signaling she understood before signing a form stating that she had walked into the clinic of her “own free will.” But she could not shake her nervousness. As she prepared to leave, Ms. Moreno offered to walk her to her car.

The woman smiled and politely accepted.

Robert Gebeloff contributed reporting.