In one instance, the federal lawsuit alleges, the pregnant woman was placed in solitary confinement for having a library book that had pictures and envelopes inside it.

In another instance, a pregnant inmate had three pairs of shoes instead of two.

In none of the instances in which five pregnant women were held for up to 22 days in solitary confinement at the Allegheny County Jail were any of them accused of any kind of violence while incarcerated.

They now are suing, alleging cruel and unusual punishment, as well as due-process violations, for being held in cells for up to 24 hours a day without adequate prenatal care or nutrition. Three of the women still are inmates at the jail.

“Anecdotally, they’re using [solitary confinement] as the first and last resort for discipline or to express disappointment,” said Bret Grote, the lead attorney on the lawsuit filed Monday in U.S. District Court.

The 26-page complaint demands that jail administrators immediately stop placing pregnant women in solitary confinement and adhere to constitutional obligations for health and safety of pregnant women, including providing a healthy diet, prenatal vitamins and necessary supplements.

The complaint also asks that the administration be required to provide hearings for inmates prior to being subjected to solitary confinement — which sometimes occurs in the infirmary or traditional cells and is often a status at the jail rather than a physical location.

County spokeswoman Amie Downs said the county does not comment on pending litigation.

She did, however, share the jail’s policy for using solitary confinement. According to Warden Orlando Harper, who is a defendant in the complaint, pregnant inmates who commit minor jail infractions can be placed in solitary with medical clearance.

Pregnant inmates who commit major infractions, such as placing medication in the cheek and not swallowing it, “fighting [and] serious contraband recovery,” are transferred to the infirmary, where they are segregated but given 24-hour monitoring and a “recreation plan to ensure adequate out of cell time will be provided.”

“The conditions of solitary confinement and inadequate nutrition faced by pregnant women at ACJ are causing severe psychological anguish, constant hunger and putting them and their pregnancies at risk of permanent harm,” Mr. Grote said. “The Constitution does not permit this.”

Attorneys for the women are asking that the complaint be certified as a class-action, although it is unclear how many women are currently pregnant in the jail. Recent reports showed there were 34 in October, 38 in July and 13 in February and March.

The lawsuit also names as defendants Allegheny County, deputy wardens Simon Wainwright and Monica Long, and Sgt. Jesse Andrascik.

It was filed by the Abolitionist Law Center, the Pennsylvania Institutional Law Project, the American Civil Liberties Union of Pennsylvania and attorney David Fawcett with ReedSmith.

The lawsuit cites recommendations from the U.S. Department of Justice and the National Commission on Correctional Health Care that advise against keeping pregnant women in restrictive housing, not only because of their medical needs but also because they are “especially susceptible to its harmful psychological effects.”

Among the concerns outlined in the lawsuit is nutrition.

According to the lawsuit, the “pregnancy diet” at the jail is “nutritionally inadequate even for pregnant inmates in general population.”

It consists of three meals a day plus an evening snack. A typical meal, the complaint said, is a thin hamburger between two slices of bread with no toppings, less than a half-cup of canned fruit, less than a half-cup of canned vegetables and a half-pint of milk. The evening snack might be an egg and some peanut butter.

The complaint alleges that pregnant women routinely don’t receive those portions and often do not get any evening snack.

In a grievance filed June 8 — 12 days after she was put in solitary confinement — plaintiff Mersiha Tuzlic, 29, complained that she was in solitary even though her case was still being investigated.

“I’ve been extremely compliant and haven’t complained, even though I’ve only received one hour of rec and one shower this entire time,” she wrote. “I feel really grimy and unsanitary. I’m pregnant, restless, neurotic and emotional. The captain who put me in investigatative status isn’t responding to my inquiries. I don’t know what else to do. I just want to sit in the gym for a while. I’m claustrophobic, and it’s getting to me. If there’s anything you can do at all — anything — please consider helping me! I’m high-risk pregnancy as is, and this is driving me nuts. Thank you for listening.”

The administration’s response was, “If this is a problem, don’t come to jail.”

A report given to Jail Oversight Board members this month expressed concern about the high number of pregnant women housed at the jail and their access to proper nutrition and health care.

Board members Terri Klein and county Controller Chelsa Wagner made an unannounced visit to the jail on a Friday evening in October. In a written report, they expressed concerns about the women’s diets.

Allegheny County Common Pleas Judge Joseph Williams, who is the outgoing board chair, said no judge wants to put a pregnant woman in jail.

“Just from a business model, they’re expensive, they’re risky,” he said.

In addition to Ms. Tuzlic, the women named as plaintiffs in the complaint are Elizabeth Seitz, 28; Riva DePasse, 27; Jill Hendricks, 38; and Kiari Day, 27.