How often do you find getting your teeth drilled is the highlight of your day? Perhaps only if you are a masochist — or a stressed new mom.

Karen, who asked that her full name not be used for privacy’s sake, shared with me how a three-hour dental procedure — something she’d normally dread –provided a rare oasis of relief from her 10-week-old son Julian’s persistent cries.

“It is all a haze now, but I know I spent many afternoons feeling completely helpless,” she recalls. “He was crying; I was crying.”

Karen barely remembered those early days when she was getting only four to five hours of sleep per night. She had postpartum depression, and she’s hardly alone. One in 7 new mothers is visited by this thief of their happiness.

What causes such suffering? Medical studies find that exhaustion and persistent crying are among the top PPD triggers. A Canadian study of over 500 new mothers found that Infant crying quadrupled a mother’s risk of PPD and deep fatigue increased it by over 20 times.

“I felt like a total failure,” Karen confessed, describing her inability to calm Julian’s cries.

Once feelings of inadequacy begin to creep in, a mother’s mood can spiral ever downward, accelerating from loneliness to fear and panic and even suicide and the tragic act of infanticide.

[See: 10 Weird Mind and Body Changes That Are Totally Normal During Pregnancy.]

The Nuclear Family: a Dangerous Experiment

Unfortunately, Karen’s experience is a very common response to a totally abnormal situation: the nuclear family. Today’s parents have to be rich to have a nanny or night nurse, but up until 100 years ago, all parents had several “nannies,” namely their moms, sisters, cousins and friends. Modern mothers and fathers are raising their children without the help of a “village,” and that extra burden is taking a toll on them both physically and mentally.

Recently, Baby Center and I surveyed over 1,000 new mothers. Almost 80 percent said they routinely felt tired or exhausted. They listed sleep deprivation as their biggest stress, ahead of lack of time or money.

To add to that challenge, many new parents have almost no baby-care experience. In centuries past, most new parents closely watched and directly helped in the care of their infant siblings, cousins and neighbors. Yet, in one of the most dramatic changes ever to occur in human society, many modern parents are raising babies despite never even having held an infant before giving birth to their own.

Often, exhaustion and the challenge of settling a crying baby drains away the expected joy of motherhood. And, added stressors like lack of support, traumatic delivery, prior depression and postpartum pain are enough to push even strong and resilient women over the edge.

Misunderstandings About PPD

The word “depression” conjures expectations of weepiness and melancholy. While sadness is common, it is often overshadowed by feelings of fear, anxious hypervigilance and dread. The problems can occasionally extend into intrusive, obsessive-compulsive thoughts or behaviors, like checking the baby’s breathing many times before going back to sleep, and even psychotic symptoms, including hearing hypercritical voices delivering messages like, “You’re a terrible mother!” For these reasons, professionals more accurately refer to postpartum depression as postpartum mood disorder.

Many new mothers hesitate to reach out because of guilt or fear of being stigmatized — or because they don’t even realize they may have PPD. Fortunately, Karen recognized that she was struggling, and she had the courage to seek help.

Karen’s doctors prescribed two medications and psychotherapy. However, they failed to erase her feelings of being exhausted, overwhelmed and demoralized. Finally, her therapist suggested a new technology to give her more rest and an expanded support system. It was a smart bed for babies, which I created in collaboration with MIT-trained engineers, as a non-pharmacologic solution for PPD. The bed shushes and rocks babies to boost sleep and automatically responds to fussing with increasing levels of white noise and jiggling — much as experienced caregivers would respond — to help calm upset infants.

That’s how I became familiar with Karen. Her therapist is leading research at UC San Diego evaluating this bed.

This smart bed has a special swaddle to keep babies safely positioned on their backs all night as recommended by the American Academy of Pediatrics. Karen described how this feature also promoted her healing, “Within a week, I was able to have precious segments of rest time each day while [Julian] napped. And the true cherry on the top is that I was able to relax while he was sleeping. I knew he was safe. I could decompress.”

[See: How to Promote Safe Sleep for Your Infant.]

Understanding PPD: The Science of Infant Sleep

Scientists have done hundreds of investigations to uncover the key triggers of PPD. One leading theory has been that it is provoked by the dramatic hormonal shift that occurs in women at delivery. Unfortunately, this does not explain why it is absent in so many women, why it may take months to develop and why people with no hormonal shifts (such as fathers and adoptive mothers) can also develop PPD.

On the other hand, many studies show a link between postpartum mood deterioration and maternal exhaustion and infant crying.

Of course, parents have long noticed that babies usually sleep better — and cry less — when shushed, rocked and swaddled (even though some are initially resistant to being wrapped). But, making these techniques effective with all babies has been very elusive.

In my early years of pediatric practice, I found that even after graduating from medical school I was helpless in caring for fussy and colicky babies. Puzzled why advanced science hadn’t found a solution, I began to read everything I could about colic. Through this research, I discovered an unknown inborn response — the calming reflex — that acts like a relative “off switch “ for crying and “on switch” for sleep. (I first introduced this concept in the parent guide, “The Happiest Baby on the Block.”) The calming reflex is activated when caregivers imitate five sensations that fetuses experience in the womb, the so-called “5 S’s:” swaddling (or snug holding); the side or stomach position; shushing (or white noise); swinging (or jiggly rocking); and sucking.

This reflex sheds light on why babies quiet when shushed and bounced, and why they fall asleep during bumpy car rides. It also explains why many babies wake more frequently when placed in quiet, flat, still beds, and why parents report better sleep using swaddling, white noise machines and rocking in rocking chairs. (It also clarifies why the drone and rocking experienced during train, plane and boat travel often leads to the drowsiness and sleep for adults and children alike.)

Solving PPD: a New Optimism

Over half a million women suffer from postpartum mood disorder each year, and as many as 25 percent of their partners also experience this form of mood disorder. The good news is that new, safer methods of swaddling, white noise and rhythmic motion may offer a breakthrough in boosting infant sleep and sparing new parents the trauma of PPD.

In addition to the UCSD research, studies are starting at the University of Michigan and the University of Amsterdam to test if — by boosting infant sleep and calming crying — we can reduce postpartum mood disorder and perhaps even prevent it.

If we succeed in improving infant sleep, we may be able to reduce other serious problems triggered by infant crying and parental exhaustion, including marital discord, child abuse and neglect, breast-feeding failure, infant sleep death, car accidents, cigarette smoking and obesity (in mothers and babies).

[See: 10 Things No One Tells You About Breast-feeding.]

Plus, we may be able to help lift the haze that often clouds the miraculous first year of a baby’s life and replace the vicious cycle of despair many parents face with a more rested, secure, confident, healthy and happy experience.

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Helping Babies Sleep Can Be Instrumental in Treating Postpartum Depression originally appeared on usnews.com