Since male producing sperm deteriorate in conditions that are highly acidic, you should adjust your PH levels through your diet to create harsh conditions for male producing sperm.
Before you raid the supermarket, purchase PH test strips to test your baseline acidity so that you can assess how much work you need to do. Some women tend to be more acidic and others are more alkaline, but you can change that by simply adjusting your diet.
Dig into foods that are high in calcium and magnesium, like fresh fruits, pasta, milk, chocolate, Brazil nuts and leafy green vegetables. If you really want to up your odds to conceive a baby girl, stay away from salty food and food that is high in potassium.
If you wish to speed up the process of achieving the right pH level, douching with a solution of two tablespoons of white vinegar and water does the trick as well.