As the American economy changes and workers try to adapt, some day care centers are offering extended hours:

About 40 percent of the American labor force now works some form of nonstandard hours, including evenings, nights, weekends and early mornings, according to Harriet B. Presser, a professor of sociology at the University of Maryland. That share is expected to grow with the projected expansion of jobs in industries like nursing, retail and food service, which tend to require after-hours work.

At the same time, working hours are less predictable than they once were. ”There’s a greater variability and irregularity of schedules,” said Lonnie Golden, a professor of economics and labor studies at Pennsylvania State University. “In surveys, more and more people are no longer able to specify a beginning or end of the workday.”

Yet for years it has been a frustrating reality for parents that child care services have failed to keep pace with the changing workday, with many centers still keeping a rigid 8 a.m. to 6 p.m. schedule. Experiments with nighttime care have come and gone over the years, but lingering ambivalence about the concept led most centers to deem it financially untenable…

While overnight care is still relatively rare, evening hours are no longer so unusual, providers say. Donna McClintock, chief operating officer for Children’s Choice Learning Centers Inc., which runs 46 employer-sponsored child care centers across the country, said that demand for nontraditional hours had grown and that centers providing care after-hours care made up a large part of the company’s recent growth. About a fifth of the company’s centers have added nontraditional hours in the past few years, she said.

This sounds like an unanticipated consequence of a poor economy: childcare providers have to offer more hours as people have to accept different kinds of jobs or work additional jobs. What are the potential consequences of changing childcare schedules?