Tech companies shower their employees with perks like dry cleaning, massages and haircuts. But there is one group for whom working at a tech company can be much more difficult than working elsewhere: parents.

Facebook hosts all-night hackathons. Google has weekend laser tag retreats. Many start-ups have no parental leave policy at all, so the first employee to have a baby has to ask the company to create one.

Then there are the subtler messages. Yahoo’s chief executive, Marissa Mayer, was vocal about returning to work two weeks after she gave birth. Later, Yahoo told employees they could no longer work from home. Workers with children say they are often the only such employees on teams of 20-somethings.

The strains around these issues have burst into public view in recent weeks. In a gender discrimination trial against Kleiner Perkins Caufield & Byers, a top venture capital firm, two former partners were declined board seats because they were pregnant or going on maternity leave, according to testimony. In a lawsuit against Facebook, a former technology partner said her boss admonished her for volunteering at her child’s school one day a month, which she said was allowed by company policy. Microsoft mandated sick leave among its contractors after complaints that some were not given such benefits.