The reason I ask is I was not when my GP prescribed it for a likely milk allergy/intolerance.
I have since been told by two other GPs that soya formula contains high levels of plane oestrogens which could cause premature puberty- as early as age 7!, possible leaukaemia and cancer risks, severe dental problems etc.
I've done some digging around on the internet and am horrified by what I have found. Sure enough there is a mountain of research which corroberates what these doctors told me. One even said- "I wouldn't want one of my children on it for long."
It's also been suggested that these hormones could effect fertility and cause thyroid problems.
According to the Department of Health, Soya based formulas should only be prescribed by a GP suspecting a milk allergy etc after hydrolised formulas have been tried and refused (Pepti, Nutramigin etc) and even then not to be prescribed to infants under the age of 6 months!!