This was taken from this article https://www.consumerhealth.org/articles/display.cfm?ID=20000501001338:
HORMONAL IMBALANCES IN INFANTS Speaking of the estrogenic compounds in soy, a recent study of infants fed soy formula found that these infants had concentrations of estrogen compounds in their blood 13,000 to 22,000 times higher than babies on milk-based formula or breast milk.
FEMINIZATION OF MALES One can only surmise what the long-term biological effects of the exposure of infants, especially male infants to such high levels of adult female hormones might be. The baby boy in the first six months of his life has a testosterone tide with testosterone levels as high as an adult male. This testosterone programs him to grow into a man, to have 3-D spatial thinking, to have differences in all of his organs, including the reproductive organs. You don't see the results or the effects until he reaches puberty. We are finding now, in medical literature, a tremendous amount of alarm about the number of boys who are reaching puberty with undeveloped sexual organs with penises the size of little babies.
EARLY MENARCHE IN FEMALES We are also finding more and more girls having puberty before the age of eight. Fifty per cent of African American girls have pubic hair and breast development before the age of eight. And 3% have this development before the age of three. This is an obscene tragedy. A study of girls in the Dominican Republic who had this early menarche found one correlation; they were given soy formula as infants. We really have a tragedy in the making on our hands; we also have liability class action suits that can hopefully destroy this industry.
If you research you will find more.
My sister brought this to my attention because her little girl is seriously allergic to cow's milk. She was put on soy, when she went into hospital still being ill the specialist there said they couldn't believe she was put on soy as it is well known that soy proteins are the same as cow, therefore cause the same problems. This isn't releavant if your baby is lactose intolerant. She then did further research into soy and was really upset about what she found out, and also that it was a Dr that had put her baby on it in the first place.
Anyway, just look into it.