Men carry both the x and the y, its down to the cervical, uteral and male sperm ph that plays a part in determining sex.
Male sperm servive better in a higher ph (above 7 ) and the female sperm prefer a more acidic enviroment.
If the man has a lower ph or they have hot baths and wear tight briefs, they are more likely to produce girls.
Then if the women has very acidic cm you are more likely to have a girl.
If you want to try for a girl then bd upto 3 days before and not again until you have clearly ov'd
If the man has a high ph, which alot of men do ( between a 7-9 ) and doesn't have a bath ( males sperm are weak and die
) he has the chance of having either sex, it is then down to the women.
A womens ph needs to be over a 7 to have a higher chance of conceiving a boy, and they need to bd day before ov, day ov and day after.
You need to chart if you are trying to gender sway