Just as you slip into sublime slumber, you hear your baby's cries. So you do the nocturnal boogie down the hall, make it all better, watch your lovely child nod off, and, if you're lucky, get back to your own bed.

But not back to sleep, at least not right away. And there's a good chance you'll be awakened at least once more during the night -- or expect to be, which means your sleep is pretty much wrecked anyway.

So it goes when you're a mom. If there's one thing you can count on after the stork swoops in, it's kissing regular nights of uninterrupted, blissful sleep goodbye. Unfortunately, catching winks here and there between cries and whispers isn't the same thing. "Four two-hour sleeps is not equal to one eight-hour sleep," says Thomas Roth, Ph.D., director of the Henry Ford Hospital Sleep Center, in Detroit. "You'll end up with fragmented, inefficient sleep, which is functionally the same as sleep loss."

The day after a night like that, you may find it harder to remember things and to concentrate on work -- or your kids. Studies show that it doesn't take much sleep loss to affect how you feel. "Even one hour less sleep in a night can decrease your alertness by a third the next day," says Clete Kushida, M.D., director of the Stanford University Center for Human Sleep Research. Although you're not likely to get sick because your slumber is disturbed for a few days, a chronic lack of quality sleep isn't good for your health: If it drags on for months, it can make the immune system less efficient and impair hormonal regulation -- making you more susceptible to hormone-related diseases like diabetes. (Just what you wanted to hear after having a baby, right?) So to feel and function at your best -- as a mom, as a wife, as a human being -- you need not only enough sleep but good sleep too.

Imagine a perfect night's sleep. (You have a right to fantasize, don't you?) You'll go through several complete cycles of REM (rapid eye movement) sleep, alternating with non-REM sleep. Both kinds are important to your well-being. There are four stages of non-REM sleep, with distinct differences in brain-wave patterns. In the first two stages, your snoozing is rather light, as blood pressure and body temperature drop a bit. Soon you drift to stages three and four, for the deepest and possibly most restorative rest of the night.

Between these non-REM cycles you have REM sleep, when almost all dreams occur. Getting enough REM enhances your memory and mental sharpness the next day. A REM/non-REM sleep cycle takes about 90 minutes. Among healthy adults, there should be four to six complete cycles per night.

As the night goes on, the balance between non-REM and REM stages shifts. During the first few hours, you spend more time in non-REM sleep, particularly in the restful third and fourth stages. Later on, in the early-morning hours, you spend more time in REM, for increasingly longer periods. That's the ideal, anyway. For moms of young kids, these nice, predictable cycles fly out the window. Your sleep patterns become topsy-turvy. When you finally drag yourself back to bed after tending to your baby, "you'll probably drift off into stage one or two of non-REM sleep," Dr. Kushida says. "But if you're sleep-deprived or if you wake up frequently, you can get dumped into any stage of sleep."

It's easy to miss out on the deepest stages of non-REM and the longer stretches of dream-producing REM. After a while, you might not even remember what a good night's sleep feels like. "One of the most ominous things about being sleep-deprived is that you stop realizing you're sleep-deprived -- it's like being drunk," says Roth. "If you don't realize it, you can end up behind the wheel of a car, which could be dangerous. Sleepiness is a signal from your body to be careful of what you're doing."

But you don't have to take it lying down! Here, four common sleep-sabotaging scenarios moms are most likely to encounter, and how to triumph over each:

Stacey Colino, who writes often on health for Parenting, had her second child earlier this year.

Nighttime Feedings

1. You're nursing your infant every two to three hours through the night.

No wonder you feel like a train wreck in the morning. You're not only waking up often, but you also feel like you're on call all night, listening for your baby's tiniest peep. "Your sleep is lighter than normal, you awaken or arouse more frequently, and you feel sleepier the next day," says Roth. "It's the anticipation of being called. This sort of sleep loss can have cumulative effects over time."

Solution: Wake up the baby for a feeding before you turn in for the night, or go to bed when she does. Synchronize your sleep with your infant's. And take turns with your partner when responding to your baby's cries, whether you're breast- or bottle-feeding. That way, you'll know you can sleep uninterrupted at least half the night. "I used to pump before bed," says Leesa Chalk Suzman, a mom of two in Scarsdale, New York. "I'd have my husband give the next bottle so I could get more than two hours of sleep in a row."

When it's your turn, keep the lights dim so it's easier to drift back to the land of Nod. "With my second child, my pediatrician told me I didn't have to change his diaper after every feeding, which really helped," recalls Mary Rose Almasi, a mother of two in Somers, New York. "I'd just nurse with my eyes shut and fall right back to sleep." Having her baby sleep in the same room made it easier.

Early Riser

2. Your alarm is set for 7 a.m., but your little one wakes you up at 5:00.

Should you try to go back to sleep -- or cut your losses and get a start on the day? It's a tough call. If you're not too tired, it might be easier just to get up. But missing that last two hours of sleep means you'll miss much of the REM sleep that helps you focus and feel on the ball the next day. Wake up in the midst of that REM sleep, and you'll have problems focusing and thinking clearly.

Solution: If you're chronically sleep-deprived because your child rises before the sun, odds are you'll fall back to sleep pretty quickly, probably within five minutes, say experts. Do it: You need whatever extra shut-eye you can get, even if it's not the most restorative sleep. "When my daughter was a year old, I noticed that when I brought her into bed with us for the five a.m. feeding, she slept longer and more soundly, usually until seven," says Wendi Gilbert, coproducer of the video Sleep Like a Baby: What Every Parent Needs to Know About Babies & Sleep, and a mom of two in San Francisco. "It was never our plan to co-sleep, but at some point it came down to trying to get the most sleep possible."

But if you try to go back to sleep without success for 20 minutes or so, you may want to get up. The harder you try, the less likely you are to doze again. When you do arise, expose yourself to bright light as soon as possible, to reset your body's internal clock so that it registers daytime and helps you become alert. "When my daughter was a baby, I'd take a brisk walk with her first thing in the morning, then a shower," says Tracy Kinsey of Davie, Florida. "That always woke me up and got me ready to face my other job."

Little Sickie

3. A sick child sleeps fitfully -- and wakes you each time he tosses and turns.

This adds up to seriously fragmented sleep, and you end up with less deep and REM slumber. Don't be surprised if you then experience more vivid dreams than usual the following night. "You'll go into REM sleep much quicker the next night and have a higher percentage of REM sleep," says Jodi Mindell, Ph.D., associate director of the Sleep Disorders Center at the Children's Hospital of Philadelphia and author of Sleeping Through the Night. "It's a rebound effect -- your body is making up for what you lost the previous night." Even having just one night of frequent awakenings can make you more vulnerable to "sleep starts," the feeling of falling off a cliff as you drift off to sleep.

Solution: Share with your partner. But instead of taking turns to tend to your sick child, try to get five straight hours of sleep. One of you could go to bed at 9 p.m. and sleep until 2 a.m., while the other sleeps from 2 to 7 a.m. Unlike the nursing scenario, in which you take turns, here you establish nighttime duty by the clock. When you go to sleep knowing you don't have to wake up until 2 a.m., you'll be more likely to sleep through a little one's cries while your spouse tends to them.

"The more your sleep is consolidated, the more likely you are to get all the sleep stages you need," Mindell says. Which means you can actually feel like a functional adult the next day. With practice, you'll work out a solution that works for your family. "We got a giant stuffed rocking chair that was big enough for me to sleep in with my twin babies in my arms," says Diane Umansky, a mom of three in New York City. "Sometimes when the kids' noses are stuffed up, they can sleep comfortably only in an upright position, so the chair helps. Plus, this way I don't have to do the mommy shuffle during the night."

Bed Mates

4. Your preschooler has a habit of climbing into bed with you in the middle of the night -- and he kicks.

Research confirms what countless women have long known -- that a partner's or child's nocturnal noises, kicking, or tossing and turning can significantly compromise the quality of your sleep. And women are more easily disturbed than men. "The kicking can lead to micro-arousals, in which you wake up for a brief moment, which disrupts the continuity of sleep," explains Margaret Moline, Ph.D., director of the Sleep-Wake Disorders Center at New York Weill Cornell Medical Center. So you may reenter a lighter stage of sleep. You may not even remember waking up; often, these arousals last just 15 seconds or less. The next day, you wake up without feeling refreshed, but you don't know why.

Solution: It's easier said than done, but you need to get your child out of your bed. Wait until he falls back to sleep, then carry him back to his bed. Or put a twin mattress or a blanket and a pile of pillows on the floor near your bed, and invite him to stay in the room with you -- if he's quiet.

Ideally, you should teach your child to fall asleep by himself (without your assistance); it'll be that much easier for him to get himself back to sleep in the wee hours of the night. Having a lovey can also give your child a sense of security during the night. He'll get the comfort he craves -- and, hopefully, you'll get the zzz's you need.

CLOSE PRINT

A Good Night's Sleep -- For You By Stacey Colino, Parenting Just as you slip into sublime slumber, you hear your baby's cries. So you do the nocturnal boogie down the hall, make it all better, watch your lovely child nod off, and, if you're lucky, get back to your own bed. But not back to sleep, at least not right away. And there's a good chance you'll be awakened at least once more during the night -- or expect to be, which means your sleep is pretty much wrecked anyway. So it goes when you're a mom. If there's one thing you can count on after the stork swoops in, it's kissing regular nights of uninterrupted, blissful sleep goodbye. Unfortunately, catching winks here and there between cries and whispers isn't the same thing. "Four two-hour sleeps is not equal to one eight-hour sleep," says Thomas Roth, Ph.D., director of the Henry Ford Hospital Sleep Center, in Detroit. "You'll end up with fragmented, inefficient sleep, which is functionally the same as sleep loss." The day after a night like that, you may find it harder to remember things and to concentrate on work -- or your kids. Studies show that it doesn't take much sleep loss to affect how you feel. "Even one hour less sleep in a night can decrease your alertness by a third the next day," says Clete Kushida, M.D., director of the Stanford University Center for Human Sleep Research. Although you're not likely to get sick because your slumber is disturbed for a few days, a chronic lack of quality sleep isn't good for your health: If it drags on for months, it can make the immune system less efficient and impair hormonal regulation -- making you more susceptible to hormone-related diseases like diabetes. (Just what you wanted to hear after having a baby, right?) So to feel and function at your best -- as a mom, as a wife, as a human being -- you need not only enough sleep but good sleep too. Imagine a perfect night's sleep. (You have a right to fantasize, don't you?) You'll go through several complete cycles of REM (rapid eye movement) sleep, alternating with non-REM sleep. Both kinds are important to your well-being. There are four stages of non-REM sleep, with distinct differences in brain-wave patterns. In the first two stages, your snoozing is rather light, as blood pressure and body temperature drop a bit. Soon you drift to stages three and four, for the deepest and possibly most restorative rest of the night. Between these non-REM cycles you have REM sleep, when almost all dreams occur. Getting enough REM enhances your memory and mental sharpness the next day. A REM/non-REM sleep cycle takes about 90 minutes. Among healthy adults, there should be four to six complete cycles per night. As the night goes on, the balance between non-REM and REM stages shifts. During the first few hours, you spend more time in non-REM sleep, particularly in the restful third and fourth stages. Later on, in the early-morning hours, you spend more time in REM, for increasingly longer periods. That's the ideal, anyway. For moms of young kids, these nice, predictable cycles fly out the window. Your sleep patterns become topsy-turvy. When you finally drag yourself back to bed after tending to your baby, "you'll probably drift off into stage one or two of non-REM sleep," Dr. Kushida says. "But if you're sleep-deprived or if you wake up frequently, you can get dumped into any stage of sleep." It's easy to miss out on the deepest stages of non-REM and the longer stretches of dream-producing REM. After a while, you might not even remember what a good night's sleep feels like. "One of the most ominous things about being sleep-deprived is that you stop realizing you're sleep-deprived -- it's like being drunk," says Roth. "If you don't realize it, you can end up behind the wheel of a car, which could be dangerous. Sleepiness is a signal from your body to be careful of what you're doing." But you don't have to take it lying down! Here, four common sleep-sabotaging scenarios moms are most likely to encounter, and how to triumph over each: Stacey Colino, who writes often on health for Parenting, had her second child earlier this year. Nighttime Feedings 1. You're nursing your infant every two to three hours through the night. No wonder you feel like a train wreck in the morning. You're not only waking up often, but you also feel like you're on call all night, listening for your baby's tiniest peep. "Your sleep is lighter than normal, you awaken or arouse more frequently, and you feel sleepier the next day," says Roth. "It's the anticipation of being called. This sort of sleep loss can have cumulative effects over time." Solution: Wake up the baby for a feeding before you turn in for the night, or go to bed when she does. Synchronize your sleep with your infant's. And take turns with your partner when responding to your baby's cries, whether you're breast- or bottle-feeding. That way, you'll know you can sleep uninterrupted at least half the night. "I used to pump before bed," says Leesa Chalk Suzman, a mom of two in Scarsdale, New York. "I'd have my husband give the next bottle so I could get more than two hours of sleep in a row." When it's your turn, keep the lights dim so it's easier to drift back to the land of Nod. "With my second child, my pediatrician told me I didn't have to change his diaper after every feeding, which really helped," recalls Mary Rose Almasi, a mother of two in Somers, New York. "I'd just nurse with my eyes shut and fall right back to sleep." Having her baby sleep in the same room made it easier. Early Riser 2. Your alarm is set for 7 a.m., but your little one wakes you up at 5:00. Should you try to go back to sleep -- or cut your losses and get a start on the day? It's a tough call. If you're not too tired, it might be easier just to get up. But missing that last two hours of sleep means you'll miss much of the REM sleep that helps you focus and feel on the ball the next day. Wake up in the midst of that REM sleep, and you'll have problems focusing and thinking clearly. Solution: If you're chronically sleep-deprived because your child rises before the sun, odds are you'll fall back to sleep pretty quickly, probably within five minutes, say experts. Do it: You need whatever extra shut-eye you can get, even if it's not the most restorative sleep. "When my daughter was a year old, I noticed that when I brought her into bed with us for the five a.m. feeding, she slept longer and more soundly, usually until seven," says Wendi Gilbert, coproducer of the video Sleep Like a Baby: What Every Parent Needs to Know About Babies & Sleep, and a mom of two in San Francisco. "It was never our plan to co-sleep, but at some point it came down to trying to get the most sleep possible." But if you try to go back to sleep without success for 20 minutes or so, you may want to get up. The harder you try, the less likely you are to doze again. When you do arise, expose yourself to bright light as soon as possible, to reset your body's internal clock so that it registers daytime and helps you become alert. "When my daughter was a baby, I'd take a brisk walk with her first thing in the morning, then a shower," says Tracy Kinsey of Davie, Florida. "That always woke me up and got me ready to face my other job." Little Sickie 3. A sick child sleeps fitfully -- and wakes you each time he tosses and turns. This adds up to seriously fragmented sleep, and you end up with less deep and REM slumber. Don't be surprised if you then experience more vivid dreams than usual the following night. "You'll go into REM sleep much quicker the next night and have a higher percentage of REM sleep," says Jodi Mindell, Ph.D., associate director of the Sleep Disorders Center at the Children's Hospital of Philadelphia and author of Sleeping Through the Night. "It's a rebound effect -- your body is making up for what you lost the previous night." Even having just one night of frequent awakenings can make you more vulnerable to "sleep starts," the feeling of falling off a cliff as you drift off to sleep. Solution: Share with your partner. But instead of taking turns to tend to your sick child, try to get five straight hours of sleep. One of you could go to bed at 9 p.m. and sleep until 2 a.m., while the other sleeps from 2 to 7 a.m. Unlike the nursing scenario, in which you take turns, here you establish nighttime duty by the clock. When you go to sleep knowing you don't have to wake up until 2 a.m., you'll be more likely to sleep through a little one's cries while your spouse tends to them. "The more your sleep is consolidated, the more likely you are to get all the sleep stages you need," Mindell says. Which means you can actually feel like a functional adult the next day. With practice, you'll work out a solution that works for your family. "We got a giant stuffed rocking chair that was big enough for me to sleep in with my twin babies in my arms," says Diane Umansky, a mom of three in New York City. "Sometimes when the kids' noses are stuffed up, they can sleep comfortably only in an upright position, so the chair helps. Plus, this way I don't have to do the mommy shuffle during the night." Bed Mates 4. Your preschooler has a habit of climbing into bed with you in the middle of the night -- and he kicks. Research confirms what countless women have long known -- that a partner's or child's nocturnal noises, kicking, or tossing and turning can significantly compromise the quality of your sleep. And women are more easily disturbed than men. "The kicking can lead to micro-arousals, in which you wake up for a brief moment, which disrupts the continuity of sleep," explains Margaret Moline, Ph.D., director of the Sleep-Wake Disorders Center at New York Weill Cornell Medical Center. So you may reenter a lighter stage of sleep. You may not even remember waking up; often, these arousals last just 15 seconds or less. The next day, you wake up without feeling refreshed, but you don't know why. Solution: It's easier said than done, but you need to get your child out of your bed. Wait until he falls back to sleep, then carry him back to his bed. Or put a twin mattress or a blanket and a pile of pillows on the floor near your bed, and invite him to stay in the room with you -- if he's quiet. Ideally, you should teach your child to fall asleep by himself (without your assistance); it'll be that much easier for him to get himself back to sleep in the wee hours of the night. Having a lovey can also give your child a sense of security during the night. He'll get the comfort he craves -- and, hopefully, you'll get the zzz's you need.