There is some confusion about the best position for a newborn baby to sleep in: on her back, on the side or on her stomach.
We are talking of course only about the first few months of life, before baby has the ability to turn on to her side and on to her stomach when she will choose the best and most comfortable position for her to sleep in.
On the stomach
We were earlier advised that babies were to be put on their stomach to sleep, because they sleep more soundly that way. This also takes care of stomach distension or mild colic, when they are laid on their stomachs to sleep it was thought.
However, later research revealed that this position of sleep is not safe for the baby, and it increases the chance of suffocation for the baby. This sleep position is also associated with an increased risk of Sudden Infant Death Syndrome, commonly known as cot death.
On the back
Research has proved that this is a far safer sleep position for the baby[baby sleep], since lying on the back reduces the risk of SIDS by up to 50%. It is possible that a baby finds this position less comfortable, in which case, swaddling the baby snugly will make, her feel a lot more comfortable and secure.
On the side
A newborn is not able to turn on to her side yet; nor is she able to maintain that position if she is put in it. However, many babies can sustain that position in sleep particularly if they are supported by a small bolster or rolled up blanket tucked up into their sides.
If your baby is comfortable and sleeps well on her back then let her do so, and when she is awake let her lie on her stomach for some stretches of time, to help with muscle development. She will also find it more interesting and will give her a physical and visual different perspective.
Sometimes it may be indicated that a baby be made to sleep on her stomach; this may particularly be the case if a baby has any kind of respiratory problems and/or upper airway malformations. If a baby also spits up a lot, it may be recommended that she be put to sleep on her stomach for her own safety.
If a baby is simply unable to get comfortable on her side or her back, you can consult with the doctor to see what the precautions to be taken are, if a baby is to be put to sleep on her stomach, such as a firm mattress etc.