When Kami Lewis Levin had her first child seven years ago, she wanted to make a clean cut from work while on maternity leave. But as a first-time mom who loved her job mentoring new teachers in New York City’s public school system, she didn’t know the best way to do it. So when her leave began, she just told the teachers to email her if they needed anything.

And email they did, often 20 to 30 times a day.

“Once you’ve built a relationship that’s so based on support and trust, it’s really hard to be like ‘I’m gone, I hope you have a great rest of your year,’” Levin recalls.

When her second child was born in 2008, Levin was in a different job, and again tried to keep her colleagues at arm’s length, especially after her newborn had trouble gaining weight. But amid a cratering economy, a new project launch at the office, and an easy connection to email via her iPhone, she found it hard to resist work’s “addictive” pull. Her colleagues didn’t help — Levin wrote a simple thank-you email for a baby gift only to receive a barrage of new messages. “It was like, ‘okay, she’s back online.’ ”

Levin’s experience isn’t unusual. For many women today, maternity leave is not the out-of-sight, out-of-mind experience it once was. More and more women are reaching positions of power that make signing off for three months more challenging. Marissa Mayer, who was named to Yahoo’s top job when she was six months pregnant, ignited a firestorm for saying her leave would be “a few weeks long” and that she would ”work throughout it.” But she’s only the most visible example of what other women in various entrepreneurial or professional roles have been increasingly trying to navigate for years.

In addition, a brutal job market means heightened concerns about going cold turkey on work email for three months. Even if legal protections are in place for jobs while on maternity leave, a teetering economy can leave many women feeling nervous. They’re not only willing to stay connected to work, they’re afraid not to be. “Job insecurity is pretty rampant,” says Ellen Galinsky of the Families and Work Institute, a research organization that studies workplace trends.

Finally, and perhaps most important, it’s hard to overstate the role technology has played in blurring the lines of our professional and personal lives. Between the prevalence of working remotely, telecommuting, and emailing from smartphones at night and on weekends, being “out of the office” no longer means what it once did. If employers expect people to respond from vacation — and surveys show many do — can expecting the same from someone on maternity leave be that far behind?

Legal experts and work-life gurus say it is, in fact, farther behind than we might think. More often than not, they say, it isn’t the employer who breaks maternity leave’s traditionally sacrosanct wall between home and office. It’s the woman on leave. “My number one observation is that the professional employee is ten times more likely than the employer to be pushing for communication,” says Garry Mathiason, chairman of the global employment law firm Littler Mendelson. “The assumption might be that the employer is trying to squeeze work out, but I’ve found that the employee — especially a professional looking at advancement — is incredibly reluctant to give up control.”

Cali Williams Yost, who consults for major companies on work-life balance issues, agrees: “I really do find in most organizations there is a respect for the maternity leave,” she says. “The confusion happens because people ask if you want to stay cc’ed on email while you’re away, and then you respond, and then it’s ‘oh I just have a quick question.’ ” Once women open the floodgates, often unintentionally, what might start as a trickle of email from the office can become a deluge.

It’s easy to see how it happens. For hard-working professional women accustomed to overloaded calendars and constant communication with colleagues and customers, the isolation of maternity leave can be a shock. After the birth of my first child, I used to joke with my husband that for the sanity of new mothers an iPhone should be just as mandatory as a car seat when leaving the hospital. Yes, bonding with your baby during middle-of-the-night feedings is a wonderful thing, but when you’re stuck in a chair nursing several hours every day, that smartphone can also feel like a much-needed lifeline to the outside world.

One reason employers may not be the one initiating contact more often — even as they squeeze more work out of everyone else — is fear. HR directors “are very careful that the contact is employee directed and not employer initiated,” says Dina Bakst, an attorney and co-founder of A Better Balance, an organization that advocates for the legal rights of caregivers in the workplace. She says employers are concerned they will violate the Family Medical Leave Act protections many women use during maternity leave.

For exempt or salaried employees, answering a few emails or passing along information is unlikely to create such a risk. But if they work anything more than “de minimis” amounts of time during the week, Mathiason says, it could technically trigger an obligation for employers to pay up. While it’s a legal anomaly that few women ever pursue, it raises enough concerns among employers that they tend to hold back.

What happens much more often, according to Mathiason, is that professional women are upset when they aren’t allowed to continue communicating with clients, directing projects or managing their teams while on leave. In fact, pregnancy-related litigation is actually up in recent years, he says, as more women come back from maternity leave, get laid off several months later for reasons that may be unrelated to their leave, and argue they weren’t kept in the loop while they were away.

As a result, the challenge leaders of organizations face today is to strike a balance between policy protections and the interest some women have in staying connected. “What we’re seeing is 20th-century workplace practices in a 21st-century world,” Yost says. “The always-connected workplace was overlaid on these old policies, so there’s a lot of misunderstanding.”

Leaders need to allow women to make choices about how much they want to communicate during maternity leave. But, says Leslie Perlow, a Harvard Business School professor and author of “Sleeping with Your Smartphone,” they also need to help their high-ranking female employees see what harm it causes when they try to micromanage things too much while they’re away. “It’s a very slippery slope,” she says. Reaching out regularly to a woman on maternity leave is “actually negative for the organization and the individual,” as the mother can end up feeling like she missed out on the precious first few months of her baby’s life, while the organization can lose out on a chance to develop additional leaders in her absence.

The way it works best is when women set clear boundaries while they’re away so that technology doesn’t “bulldoze the barriers,” as Levin puts it, between work and home. Were she to do it all over again, she hopes she would feel less stress and guilt about being away. “If you’re going to check in once a week, check in once a week and be like clockwork about it,” she says. “The clearer you can make it for yourself, the more respectful everyone’s going to be.”

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