No proof of that either. If youre referring to problems with androgen and testosterone production during gestation then youd see a higher rates of homosexuality in intersex disorder victims and we dont.
Obviously gestation is very complex and has different stages. The connection between the development of the genitals and parts of the brain is certainly not fully understood. Studies of finger-length ratios suggest that male homosexuals might even have a higher-than-normal level of testosterone in utero. I would assume that with intersex cases the problem is often the opposite.
It is well established that a group of women whose mothers took a particular drug to avoid miscarriage grew up to be unusually promiscuous. I have met one of these women (dated her sister). So clearly the pre-natal environment can affect one's adult sexual nature.