You’re back to work, coffee in hand, hanging in there because you’ve read that babies start to sleep through the night by around 4 months. Apparently your baby missed that chapter. When will she let you get enough rest? That’s what neuroscientist and sleep researcher Polly Moore, PHD, wondered after she had her first child. When she noticed that her baby seemed to get tired after being awake for about 90 minutes rather than randomly, she created a biological-rhythm-based strategy that leads to more predictable naps and bedtimes. “Nighttime awakenings start to recede once babies get the rest they need during the day,” says Dr. Moore, author of The 90-Minute Baby Sleep Program. In a nutshell, here’s her “naps” program for you to try and to share with your caregiver: Note the time when baby wakes up. Add 90 minutes. Play, feed or pursue other activities during the 90 minutes, then Soothe your baby back to sleep by rocking or other methods you’ve found to work. Repeat the cycle if your baby wakes again.