Some women do not produce enough milk and have the true inability to produce enough milk, but it is very rare, and usually related to hormone disorders or underdeveloped breast tissue, the mom common scenario is that women have a decrease in supply due to preventable factors, such as not nursing frequently enough, a baby with a poor latch who does not drain the milk well, a variety of other problems,and the less you take out, the less you make. Chances are you will be just fine in terms of milk supply. Nurse baby on demand, get help from a LC if you are having latch problems. The baby is the best pump there is, but if you are going to work and need a pump anyways, try renting a hospital grade pump, the better the pump, the more milk you will get. The best thing you can do to have a good supply is to latch baby deeply, and nurses as often as baby wants to. The more you nurse, the more milk you will have.