The Helen Hayes Theater, now being renovated after being sold to the nonprofit Second Stage Theater, is also getting a major upgrade: The cramped women’s room, which had five toilets, has been demolished and will reopen with 10; the men’s room, which had one toilet and three urinals, will reopen with two toilets and four urinals. The theater is also adding two bathrooms with access for those with disabilities.

And more is ahead: Jujamcyn Theaters plans to add three additional women’s stalls, one men’s stall and three urinals to the St. James, as well as reconfigure that building’s lobby to allow bathroom lines to flow better, as it expands the theater between a run of “Present Laughter” and the much-anticipated stage adaptation of “Frozen.” The Nederlander Organization expects to renovate the Palace Theater, currently home to a revival of “Sunset Boulevard,” as part of a development project that will involve lifting the theater 29 feet and will create more space for bathrooms. And the Shuberts anticipate renovations at three theaters: the Ambassador, the Cort and the Lyceum.

The challenge is clearly visible these days at many shows, including “Waitress,” a hit musical that, with a story about empowerment, a song about pregnancy testing and a joke about estrogen asphyxiation, is drawing a heavily female crowd.

At one evening performance last week, the line for women zigzagged from one side of the mezzanine to the other and back again, contained by ropes, organized by ushers, overflowing into stairwells, hemmed in by a bar. Two ushers controlled the line; a third stood at the bathroom entrance directing women to specific stalls.

“We do this eight times a week,” an usher said. “We have a system.”

As the lights dimmed for Act II to begin, an usher sent six women still waiting in line to the men’s room.

That scene has been playing out throughout the run of the show — at a matinee performance last year, several women sitting in the orchestra section bolted down the aisle as soon as “Bad Idea,” the final song in the first act, began to play; during the intermission, ushers were radioing stage managers to give updates about the line progress.