Introduction: Overweight and obesity are among the most serious public health problems in the world. Today, about half of adult men, one third of adult women and one in five children are estimated to be overweight or obese. Being overweight is not considered as a disease, but it can lead to obesity, which puts the individual at high risk of suffering from several diseases such as diabetes type 2, high blood pressure. To define whether an individual is overweight, normal weight, obese or underweight, BMI value is used. Polycystic ovary syndrome (PCOS) is an endocrine disorder that affects women in fertitlity age. The syndrome is associated with several of risk factors such as insulin resistance, obesity, cardiovascular problems, and infertility. Imbalances in the hormones produced by ovaries can be a cause of PCOS.Currently, there are three prescription drugs in Sweden to treat obesity such as liraglutide (Saxenda®), bupropion/naltrexone (Mysimba®) and orlistat (Xenical®).Objectives: The purpose of this study was to investigate the effectiveness of using liraglutide as monotherapy or in combination with metformin to treat women who were overweight or obese and affected by polycystic ovarian syndrome.Method: This study is based on four randomized controlled clinical trials studies, which are taken from the PubMed database. Using these keywords “liraglutide, obesity, weight loss, BMI, treatment, metformin, PCOS”.Results: The greatest weight loss was observed in study 4 in obese women with PCOS, whichwere treated with the combination of both liraglutide 1.2 mg/day and metformin 1000 BID/day. A weight reduction of -9.23 ±1.23 after 12 weeks of treatment was observed. While less weight loss of -3.0 ± 0.6 kg was observed in study two, where obese women with PCOS were treated with liraglutide 1.2 mg/day and metformin 1000 mg BID/day as a monotherapy. In study 1, obese women with PCOS treated with the combination of both liraglutide 1.2-± mg/day and metformin 1000 BID/day had a weight loss of -6.5 ± 2.8 kg. The obese women with PCOS in study 3 were treated with liraglutide 3 mg/day and had a weight loss of -6.3 ± 3.7 kg butexperienced more severe GI adverse events.Conclusion: The four studies showed that short-term treatment with liraglutide, which is a GLP-1 receptor agonist, 1.2 mg/day together with metformin 1000 mg BID/day as a combination therapy is associated with significantly greater weight loss, BMI changes and with changes in waist circumference compared to when treated with liraglutide or metformin as a monotherapy