Bed sharing between a mother and her baby is an old and treasured practice in many parts of the world. It evolved to protect and feed babies through the night and is linked to many benefits for both mother and child. These include more breastfeeding, loving contacts, infant movement, awakenings, less crying and longer sleep than for babies who sleep alone.
Sadly, there are some situations that make bed sharing less safe, especially for young babies (under 4 months). The most serious is when there has been smoking in pregnancy. This smoking / bed sharing combination can lead to sudden infant death syndrome. While most babies survive this situation, some do not.
Bed sharing is common in NZ. The NZ Cot Death Study found that it was more common for Maori (66%) and Pacific (74%) babies than European (36%). Overall, 45% of the 1592 babies in the study shared a bed.
Also risky, is sleeping with a baby after taking drugs, after heavy drinking, if the adult is very obese or sleeps heavily, and sleeping with a baby on a sofa. We know from research studies that these things have led to accidental suffocation from overlaying for some babies.
One in three NZ babies is born to a woman who smoked in pregnancy. It is these babies, from smoking families, that face an extra and major risk for SIDS when they also bed share. It is not known for sure how or why this is so. It may be that damage from smoking in pregnancy makes some babies more vulnerable to problems during sleep.
One third of all deaths from SIDS is linked to this mix of practices – bed sharing with babies exposed to smoking. There is 5 times the risk of SIDS for such babies compared to babies not exposed to either practice.
Two of many chemicals from smoking that harm a baby during pregnancy are nicotine and carbon monoxide. They harm babies in many ways – ways we cannot see on ultra- sound scans or with our eyes. Nicotine harms a baby’s defence and survival mechanisms. It damages heart and lung functions that control how a baby responds to stress. Carbon monoxide stunts the growth and development of body organs. It damages how they work by reducing oxygen supply at a critical time. If there was smoking in pregnancy
It then becomes important for a baby's protection to delay sleeping together with a baby for the first 6 months of life. Bed sharing with a baby is safe when adults are aware and awake. It is when they have reduced awareness and are sleeping that the risk exists.
Parents have a lot of control over the safety of their baby’s sleep. Safe choices will depend on whether or not a baby is smokefree (during and after pregnancy), the state of awareness of the bed sharing adult and the sleeping place itself.