Cosleeping and Overlaying/Suffocation: Is there a chance I'll roll over and crush my child?
To claim that there is NO chance of an adult overlaying a baby would be irresponsible, but so would it be irresponsible to claim that an infant could never be killed while traveling in an automobile, or while sleeping alone in a crib which has an overly soft mattress, or crib slats which do not prevent the infant's head from passing between them. In each case, the dangers are significantly reduced - and the potential benefits of car travel or infants sleeping alone (where this is what parents want) can be realized -- when the safety precautions unique to each choice of behavior are regarded. In the case of automobile travel, strapping infants correctly into a consumer safety approved car sits, and not driving while under the influence (of drugs or alcohol) makes car transportation worth the relatively small risk such travel imposes.
No infant sleep environment is risk free. As regards cosleeping (in the form of bed-sharing) what we know to be true scientifically is that for nocturnal infant breast feeding and nurturing throughout the night both mothers and babies were designed biologically and psychologically to sleep next to one another. And while beds per se did not evolve mother-infant cosleeping most assuredly did-and not maximize infant and maternal health and infant survival! Infant-parent cosleeping with nocturnal breast feeding takes many diverse forms, and it continues to be the preferred "normal" species-wide sleeping arrangement for human mother-baby pairs. In the worldwide ethnographic record, mothers accidentally suffocating their babies during the night is virtually unheard of, except among western industrialized nations, but here there are in the overwhelming number of cases, explanations of the deaths that require reference to dangerous circumstances and not to the act itself.
Let me expand a bit on what we know to be true scientifically. Anthropological and developmental studies suggest that mothers and infants are designed to respond to the presence of the other, and no data have ever shown that among mother-baby pairs who cosleep for breast feeding in a safe cosleeping/bed-sharing environment that mothers are unable to sense the proximity of their babies in order to avoid smothering them. Our own laboratory sleep studies of cosleeping/bed-sharing mothers infant pairs (2 to 4 month olds) reveal that both breast feeding mothers and their infants are extremely sensitive throughout their night - across all sleep stages - to the movements and physical condition of the other. The healthy infant, which includes most infants, are able to detect instances, where for example, their air passages are blocked. They can respond very effectively to alert the mother to potential danger, and they have the physical skills to maneuver out of danger, under normal circumstances. That being said, modern societies and the objects on which we sleep and the social and physical conditions within which bed-sharing can and often does occur especially among the urban poor forces professionals to be very guarded when discussing bed-sharing and/or cosleeping. The truth is that there is no one outcome (good or bad) that can be associated with cosleeping in the form of "bed-sharing, but rather a range of outcomes (from potentially beneficial to dangerous and risky) depending on the overall circumstances within which the cosleeping takes place.
For example, the condition of the sleeping surface - the bed (in Western cultures) and the condition and frame of mind of the adult cosleeper (s), and the purposes for cosleeping --are very important in assessing the relative safety, dangers or potential benefits of sleeping with your infant or child. During my many years of studying infant-parent cosleeping/bed-sharing, I am unaware of even one instance in which, under safe social and physical conditions, a mother, aware that her infant was in bed with her, ever suffocated her infant. But just as is true for other aspects of infancy or childhood important precautions need to be taken if families elect to bed-share For example, bed-sharing should be avoided entirely if the mother smokes (either throughout her pregnancy or after) as maternal smoking combined with bed-sharing increases the chances of SIDS.
While there is evidence that accidental suffocation can and does occur in bed-sharing situations, in the overwhelming number of cases (sometimes in 100% of them) in which a real overlay by an adult occurs, extremely unsafe sleeping condition or conditions can be identified including situations where adults are not aware that the infant was in the bed, or an adult sleeping partners who are drunk or desensitized by drugs, or indifferent to the presence of the baby. In these cases often the suffocation occurs while the parent and infant sleep on a sofa or couch together.
In my own work I stress that a distinction must be made between the inherently protective and beneficial nature of the mother-infant cosleeping/breast feeding context, and the conditions (of the mother and the physical setting including equipment) within which it occurs - which can range from extremely safe to unsafe and risky.
While mother-infant cosleeping evolved biologically, it is wise to recall that beds did not; whether sleeping in a crib or in the adult (parental) bed, the mattress should be firm and it should fit tightly against the headboard so that an infant cannot during the night fall into a ledge face down and smother. Since contact with other bodies increases the infant's skin temperature, babies should be wrapped lightly in the cosleeping environment especially, and attention should be given to the room temperature. Obviously if the room temperature is already warm (say above 70 degrees F, the baby should not be covered with any heavy blankets, sheets or other materials A good test is to consider whether you are comfortable; if you are, then the baby probably is as well.
I would avoid cosleeping with a baby on a couch as too many that I know of slipped face down into the cracks between the pillow seats and were compressed against the back wall of the couch, or fell face down into the back part of the couch and suffocated. Personally, I would also avoid cosleeping on waterbed, although there may be some instances they are firm enough and lack deep crevices (around the frame) that could be deemed safe.
Under no circumstances should the baby sleep on top of a pillow, or have it's head covered by a blanket. Moreover, if another adult is in the bed, the second adult should be aware (made aware of) the presence of the baby, and it should never be assumed that the other adult knows that the baby is present. Parents should discuss with each other whether they both feel comfortable with the baby being in the bed and with them. I always suggest that if parents elect to cosleep in the form of bed-sharing each parent (and not just one) should agree to be responsible for the baby. Such a decision, by both sleeping adults, maximizes attention to the presence of the infant.
Toddlers or other little children should not be permitted to sleep in the adult bed next to an infant as toddlers are unaware of the dangers of suffocation. Moreover, it is safer not to permit an infant and a toddler to sleep alone together in the same bed.
Finally, it is not a pleasant thought to consider, but I always think that it is important to consider if, by chance, an infants died from SIDS while sleeping next to you, would you assume that you suffocated the infant, or would you know that you did not, that the infant died independently of your presence? If you are unable to believe that a SIDS could occur independent in the bed-sharing or bed-sharing/breast feeding context, just as it can under perfectly safe solitary sleeping conditions, then perhaps it might be best to have the your infant cosleep next to you on a separate surface, rather than actually in your bed. Regardless of what you decide, it is important to consider the possibility, no matter how remote and unlikely such a scenario may be. That SIDS can, indeed, occur, where safe bed-sharing, breast feeding and complete nurturing and care for the infant has occurred, makes this question worth discussing amongst you and your partner.
Let me end on a positive note: all else being safe, bed-sharing among nonsmoking mothers who sleep on firm mattresses specifically for purposes of breast feeding, may be the most ideal form of bed-sharing where both mother and baby can benefit by, among other things, the baby getting more of mother's precious milk and both mothers and babies getting more sleep - two findings which emerged from our own studies.