When a child wants to climb a tree for the first time, do you wait until they've developed the capability completely on their own, or do you help them, steady them, and be there in case they fall?
The same is true of walking. Probably since the beginning of communication, people have expressed different opinions about this. But long before that, babies have wanted to walk long before they were able to do so on their own, and parents have played the little game of holding their hands/wrists (not just hands) and doing so with their delighted child. Because it pleases their child, and there's nothing wrong with it. When the baby is tired, they'll signal that it's time to stop by not supporting their weight.
There is nothing wrong with it. In fact, on the used-worldwide Denver Developmental Milestone Screening Test, there's a specific entry for this - BEAR WEIGHT ON LEGS - starting at 2 months. Obviously at two months they can't pull their way up to the standing position. In this case, they stand on your lap while you hold them by the torso. I have always asked this question in my well-baby check ups. No one has ever asked if it was bad for the baby. I don't know where or when this myth arose, but it is a myth.
It is not only not harmful for the baby, but a normal part of gross motor development.
Edited to add: As to the use of the baby walker (which I didn't address in my answer; I referred to holding a baby's wrists to help them walk when they so desire), Pediatricians do warn against them for fear of injury. There are also studies that report that walking on their own is delayed by one to two weeks.
From the American Academy of Pediatrics position paper:
Because data indicate a considerable risk of major and minor injury and even death from the use of infant walkers, and because there is no clear benefit from their use, the American Academy of Pediatrics recommends a ban on the manufacture and sale of mobile infant walkers. If a parent insists on using a mobile infant walker, it is vital that they choose a walker that meets the performance standards of ASTM F977-96 to prevent falls down stairs. Stationary activity centers should be promoted as a safer alternative to mobile infant walkers.
The Academy does admit that parents perceive their babies derive pleasure from walkers. The point is they don't think the risk is worth the benefit.
Again, in the AAP practice guidelines for injury prevention in the first year of life, the pediatrician is directed to ask:
- Do you ever place your baby in an infant walker?
and the following is the recommendation given to discuss with the patient:
Do not place your child in a walker. Every year, more than 8,000 injuries occur to children in walkers.
As a physician, I do not recommend baby walkers because babies do get injured in them. I believe the media hype is frenzied, but that is my personal opinion. Nonetheless, I would no more recommend them than I would recommend allowing one's child to crawl unsupervised at the top of an open staircase, because of the risk of injury (not because I think crawling at the top of an open staircase retards motor development or intellect.)