This is the same question I asked my hubby while we were at the mall's infant wear section. He ain't got a clue also.
My hubby and I are very practical people. We only purchase stuff that we really need (and boy, whatta difficult task it was steering away from adorable baby girl clothes!). And since we thought the baby blanket was just an ordinary tiny blanket, we skipped buying it that day.
I only realized what a baby blanket is during one of our OB-Gyn visits. My OB-Gyn shares her clinic with a pediatrician. So obviously the waiting area's not only crowded with other preggy women like me, but also with other mums carrying babies.
All of the newborns were wrapped in blankets. But not just ordinary blankets, blankets with hoods! Then it dawned on me that these are the so called baby blankets!
With further research (and tons of questions thrown at my OB-Gyn), I learned its importance. Let's state the obvious, it keeps the baby warm. And I was told that the hood protects the baby's head from hamog during early morns and evenings.
"Hamog" if I'm not mistaken, is fog in English. So how come the elderly warn the parents "Baka mahamugan ang bata." (Transliterated: The baby might get fogged.) when there isn't really any fog happening (we live in the mountains however, so this applies to us)? Beats me.
I have read online that 30%, some say 45%, of a human's body heat is lost through the head (this is now considered a modern myth though). Could this be the reason?
A more important role of a baby blanket, when wrapped snuggly around a newborn, is that it gives a feeling of security. It imitates the womb's environment. It is believed to give the baby a deep sleep too (don't keep your hopes high, a newborn still wakes up every couple of hours to feed!)
Pointers in choosing a good baby blanket? Just make sure that it is of good quality (I got my bet on cotton). Not too thick during summer and not too thin during winter/rainy season (or again, if you live in the mountains like us).