Polycystic ovary syndrome can lead to metabolic abnormalities associated with insulin resistance, which can cause increased blood glucose. Patients with polycystic ovary syndrome take metformin because it increases glucose uptake and reduces hepatic glucose production, thereby reducing insulin resistance. The most common adverse reactions in patients with polycystic ovary syndrome who take metformin are gastrointestinal reactions, which may include diarrhea, bloating, and nausea. Contraindications to metformin include type 2 diabetes mellitus combined with acute severe metabolic disorders, severe infections, hypoxia, trauma, major surgery, pregnant and lactating women, people who are allergic to the drug or who have had a serious adverse reaction to the drug, and alcoholics. Patients with polycystic ovary syndrome need to consult a professional physician before taking metformin and follow the doctor’s instructions to standardize the use of medication.