The more you suck the milk with a breast pump, the less you suck it may be due to the following reasons: 1. For example, not having a good rest after giving birth, being too tired or not having enough sleep can lead to a decrease in milk secretion or not having a good adjustment in diet and drinking less soup. It is recommended to drink more chicken soup, fish soup, meat soup, bone soup to promote milk secretion and make more and more milk.