The Rev. Patrick J. Mahoney, of the Christian Defense Coalition, speaks Monday of the death of a local woman who died from possible abortion complications. A memorial, prayer vigil and a press conference were held by various anti-abortion groups. (Michael S. Williamson/The Washington Post)

The Maryland Office of Health Care Quality is investigating the death of a woman who visited a controversial abortion clinic in Germantown before dying last week at a local hospital.

More than 150 demonstrators gathered near the clinic Monday to step up their efforts to draw national attention to the case, asserting that the clinic’s leader, LeRoy Carhart, was directly responsible for the woman’s death and that she had come to his office for a multi-day abortion procedure when she was 33 weeks pregnant.

“We will not rest until this clinic is shut down and the license of LeRoy Carhart is revoked. God let it be so,” the Rev. Patrick Mahoney, director of the Christian Defense Coalition, said at the demonstration.

The circumstances leading to the woman’s death remained unclear Monday. State and county officials confirmed that she had visited the abortion clinic and that she died Thursday morning at Shady Grove Adventist Hospital, but they offered no details.

Antiabortion demonstrators seized upon the incident to try to sway public opinion about late-term procedures. Many of their specific claims about the case could not be immediately verified.

About 150 people attended a memorial, prayer vigil and a press conference Monday by various anti-abortion groups in Germantown, Md. (Michael S. Williamson/The Washington Post)

Speakers at the rally said the woman, 29, arrived at the clinic Feb. 3 from New York. They asserted that she had recently learned of medical problems with the baby she was carrying. “It was a perfectly healthy young woman that died,” said Michael Martelli, executive director of the Maryland Coalition for Life.

Carhart did not respond to requests for an interview.

His facility has become a touchstone for the abortion debate nationwide. Opponents have launched regular demonstrations there, accusing Carhart of regularly performing late-term and dangerous abortions. Abortion-rights advocates say Carhart, who lives in Nebraska but flies to Maryland to operate the clinic, courageously performs procedures that other physicians won’t.

The Maryland Office of the Chief Medical Examiner has conducted an autopsy of the woman, but a complete review could take a month or more. The medical examiner’s office reviews about 10,000 cases a year. The family of the dead woman, preparing to bury her this week, could not be reached for comment. An online gift registry linked to her and her husband indicated that her pregnancy had been wanted.

Still unclear was whether the woman was as far along in her pregnancy as the demonstrators say and, if so, why she sought an abortion so late. The gift registry indicated a due date of March 20. Also unknown was the nature of the fetus’s medical condition and whether the health or life of either mother or child was at risk.

In Maryland, late-term abortions — those that occur when the fetus is developed enough to survive — are legal when the life or the health of the mother is at stake or when the baby develops a fetal abnormality. Many other states, including Virginia, allow such procedures only when the health or life of the mother is at risk and only when two doctors draw the same conclusion.

In the Germantown case, Martelli said, the woman and her family were staying at a local hotel during the multi-day procedure. The woman was taken to Shady Grove on Thursday morning, he said, and died a short time later.

Tricia Nay, the medical director of the state’s Office of Health Care Quality, confirmed the office is looking into the matter. “We are aware of this incident, and we do have an ongoing investigation,” she said.

Carhart, one of the few doctors in the nation who openly acknowledges performing abortions late in pregnancies, began practicing in Germantown in late 2010. Since then, antiabortion activists have tried to talk to patients as they make their way to his facility, which is in the middle of a nondescript office park. One of those activists said Monday that she had tried to speak with the woman last week on one her visits to the clinic but was unsuccessful.

On Monday, opponents of abortion carried signs with statements such as “A fetus is a child” and “Life is not a choice.” One demonstrator held up a large photograph of the woman who died, identifying her by name next to the abbreviation “R.I.P.”