I sometimes hear from women who have just married (or are seriously dating a man) and they are trying to gauge which baby gender this man might help them to produce. Some people may find this desire petty or silly. But I understand this inclining. Many women have dreamed about the child that they might have all their lives. And, many are already married and committed to the relationship no matter what gender might be in their future. So, although they are curious about which gender they are more likely to produce, it's not as if they are going to end the relationship if they do not get the gender they want.
I heard from a woman who said: "I was married six months ago In a few more months, we want to start trying to have a baby. take to make sure that he can conceive a girl? Or to tell me which sex he's most likely to conceive? "
This woman may be happy to know that, barring some sort of injury or illness, a health man is said to produce equal amounts of Y perm (which produces boys) and X sperm (which produces girls.) This is one factor in ensuring that the birth rates are close to equal. She was something happy to hear this, but she was also a little disappointed that she could not do some sort of diagnostic test that was going to tell her what gender might be in her future.
It's my opinion that there is a test that you can take, but it test the woman, not the man. You can test the mother-to-be's PH. A woman who is more acidic is said to have a better chance of having a female baby because that same acid discourages the Y sperm. The test is simply done at home with a PH tester. They typically come with a chart to tell you where you fall in terms of being acidic or alkaline.
Many people mistakenly assume that if they test and find that they are acidic, then they are absolutely going to have a girl without question. Or, they assume that an alkaline reading means a boy. It does not. It only means that you have a vaginal environment that is more conducive to one type of sperm over another. Your husband, partner, or boyfriend will still probably deposit equal amounts of Y to X sperm. But, your vaginal environment may discourage some of those sperm. Still, it's likely that both X's and Y's remain, regardless of the vaginal environment. That's why it's important to do more than one thing to influence your baby's gender.
Timing your conception before ovulation (for a girl) or after it (for a boy) is one more way to discourage those sperm that you do not want hanging around and fighting for the egg. Plus, the sexual positions that you use can be classified as girl or boy friendly. All three of things are important because each one will help to discourage or get rid of the sperm that you do not want so that more than the sperm that you do want (in this woman's case, it was the X or girl sperm) have the best chance of being the first one to make it to the egg and then producing the gender that you prefer.
So to answer the question posed, while a doctor can certainly test your husband's sperm count and general health, most men have both boy and girl producing sperm in roughly equal numbers. But testing the woman's PH can tell her if her vaginal environment is more or less friendly to girl sperm. If this woman tested and found that she was alkaline (which is more friendly to boy sperm) she could change her diet or try a douching regimen to become more alkaline. And, she could conceive before ovulation as well as use the correct sexual positions.