Flat head syndrome also known as Plagiocephaly can be more common with twins or multiples as they are born earlier than singletons.
Babies, especially baby twins or those born prematurely, have very soft skulls in the first year of their lives. A flat spot on the back of the head usually develops as babies are put to sleep in one position all the time. With the “Back to Sleep Campaign” which encourages parents to put their babies to sleep on their back in order to avoid SIDS (sudden infant death syndrome) there has been a rise in flat spots on the head.
Please note that the “Back to Sleep Campaign” is very important and unless advised by your pediatrician all babies should sleep on their back. The best way to avoid the flat spots is to rotate babies sleeping positions. If the flat spot it persistent you need to mention the condition to the pediatrician as soon as possible and under severe circumstances a corrective helmet may be needed to reform the shape of the babies’ heads.
In most cases a baby’s skull will correct itself with re positioning and by 12 months you will notice a great improvement in the head.