|Posted by email@example.com on May 1, 2014 at 9:40 PM|
Judging by my e-mail inbox and the conversations I share with parents and health professionals, infant sleep has become a veritable industry. An industry, it seems, that is driven by fear—particularly the fear that if we dare to respond to little night howls with too many cuddles (or, heaven forbid, cuddles in parental beds), our babies may never learn to sleep alone.
When my own babies were small, neither social ideology nor wakeful babies caused me a lack of sleep; my babies slept snuggled up with me at night. My choice to co-sleep wasn’t based on research studies, it was simply “best practice” for our family… and how we all got the most sleep. Now there is a plethora of research about infant sleep, and I find it fascinating to compare this research to my own experience.
Recently, as I searched for some long-term evidence on the benefits of parent-infant co-sleeping, I came across a study by James J. McKenna and Thomas McDade called “Why Babies Should Never Sleep Alone: A review of the co-sleeping controversy in relation to SIDS, bed-sharing and breastfeeding.” The study, which involved college-age subjects, found that males who had co-slept with their parents between birth and 5 years not only had significantly higher self-esteem, they experienced less guilt and anxiety and reported greater frequency of sex. For women, co-sleeping during childhood was associated with less discomfort about physical contact and affection as adults. The co-sleepers had higher self-esteem than those who slept alone as children.
Although I am uncertain how to objectively validate my own (or my kids’!) experience in terms of this research, I concur with the wealth of evidence that supports co-sleeping as an integral part of mother-infant bonding. (In this article, co-sleeping is defined as mother and baby sleeping within sensory proximity of each other. This includes but is not limited to bed-sharing.)
Science confirms what instinct has always sung in the hearts of mothers: Nature prepares mothers and babies to be able to commence their attachment as soon as the baby is born. Immediately after a natural birth, certain hormones that are part of the birth process remain at high levels within the mother’s and baby’s bodies and play a crucial role in the formation of their relationship. If this delicate balance of hormones is allowed to function in the very first moments after birth—by keeping mother and baby warm, in skin-to-skin contact with each other, and free of distractions—they are exquisitely, chemically, primed to fall in love with each other.
Two of the major players in this hormonal cocktail are oxytocin, the hormone of affectionate bonds—also known as “the love hormone”—and prolactin, a hormone critical for the initiation of lactation, which is often referred to as “the mothering hormone.” Oxytocin is involved in whatever facet of love we consider—it is released during lovemaking and also has been shown to evoke maternal behavior if injected into the brains of virgin rats. Oxytocin itself is part of a complex hormonal balance. A sudden release of oxytocin creates an urge toward loving, which can be directed in different ways, depending on the presence of other hormones. This is why there are different types of love. When oxytocin is found with a high level of prolactin, for example, the urge to love is directed toward babies.
Fortunately, whatever the birthing experience, it seems nature allows more than a single chance to cement the foundation for a loving relationship and to reinforce the bonding process. Learning to love is an ongoing process for mother and baby, and hormones continue to play an important role, day and night.
As a woman breastfeeds, for instance, she receives doses of oxytocin (which stimulates the milk ejection reflex) and prolactin (which has a calming effect on her as she breastfeeds). Endorphins, the hormones of pleasure and transcendence, are also released during breastfeeding and encourage the mother to continue. In turn, endorphins are transferred through the mother’s milk to her baby, giving the child a sense of contentment as he or she breastfeeds. Since prolactin levels are highest during night feeds, it makes sense to consider that proximity to her infant at night would elevate the love a mother feels for her infant. Perhaps, without pressure to teach their babies to sleep all night as soon as possible, mothers could appreciate night-time breastfeedings as an extra opportunity to bond with their babies.
For any mother snuggling a baby against her body, nuzzling her face into her infant’s baby-fine hair and smelling that sweet newborn breath, research verifying that mothers and babies feel best when they are close to each other would hardly seem necessary. However, there is indeed scientific evidence that mothers and babies are hardwired to the experience of togetherness.
One argument in favor of continuous mother-baby togetherness maintains that infants get to know and bond with their mother through all of their senses—eye contact, the sounds of the mother’s voice, her touch and smell.
Attachment, the process of learning to love, is a behavioral system that operates 24 hours a day. It does not deactivate during sleep, where infants spend up to 60 percent of their time. As obstetrician Michel Odent observes, “It takes only the most elementary observation to see that a baby needs its mother even more during the night than in the daylight. In the dark, the baby’s predominant sense—sight—is at rest. Instead, the baby needs to use its sense of touch through skin-to-skin contact, and its sense of smell.”
According to Professor James McKenna, director of the Mother-Baby Behavioral Sleep Laboratory at the University of Notre Dame, co-sleeping is a safe and even potentially life-saving option, as long as parents provide a safe sleeping environment (see sidebar). Professor McKenna has extensively studied mothers and babies both co-sleeping and sleeping separately and his research demonstrates what co-sleeping mothers will attest to: When mothers and babies sleep together, they tend to get into the same sleep cycle. The mothers, even in deep sleep, were aware of their babies’ positions and would move to avoid lying on them or impeding their breathing. Although the co-sleeping babies spent less time in deep sleep and aroused more frequently (though not necessarily waking completely), their mothers actually got more sleep than the mother-baby pairs sleeping in separate rooms.
As a researcher in SIDS (Sudden Infant Death Syndrome), Professor McKenna explains that these small transient arousals may lessen a baby’s susceptibility to some forms of SIDS, which are thought to be caused by failure to arouse from deep sleep to re-establish breathing patterns. The babies in his studies who sleep with their mothers also tend to sleep on their backs or sides and less often on their tummies— another factor that could reduce the risk of SIDS. Professor McKenna advises, “From an evolutionary and biological perspective, proximity to parental sounds, smells, gases, heat and movement during the night is precisely what the human infant ‘expects,’ and in our push for infant independence, we are forgetting that an infant’s biology cannot change quite as quickly as cultural child-care patterns.”
For mothers who enjoy sharing sweet dreams with their babies, the research is affirming: Touch and proximity are essential elements of bonding; the hormonal status that enhances bonding is at its most effective during nighttime breastfeeding; continued breastfeeding maintains the release of hormones essential for mother-infant bonding; and breastfeeding is more likely to be successful for a longer duration when mothers and infants co-sleep.
If, despite the evidence, you are facing criticism (“You will never get him out of your bed!”), take heart: My children are no longer sleeping with me. However, now that they are of college age, according to research, it seems they could well be sleeping with somebody else!
author: Pinky McKay, IBCLC
Samford Chiropractic Centre