Are you too tired for sex?

(CNN) -- According to a recent study by the National Sleep Foundation, about one in every four married or cohabitating Americans claim they're so sleep-deprived that they're often too tired to have sex. It's not surprising why sleep trumps sex: Between work, family and social obligations, our need for shuteye often suffers. Add in problems such as financial stress, health issues and relationship woes, and you can see why sex tends to drop to the bottom of our "to do" list -- if it's on there at all. And when we do finally hit the sheets, many of us are more apt to hold onto our smart phone, tablet or other gadget than our partner's hand. Ian Kerner Ian Kerner "Many of us are multitasking throughout the day for extended periods of time -- constant stimulation that can allow for enriching experiences," says Amy Levine, sex coach and founder of Ignite Your Pleasure. "However, that can also take its toll on our sex lives."