Obesity in women is one of the leading causes of health related disorder and has reached epidemic proportions not only in developed nations but also in developing countries like India. It is a life-threatening condition as it shortens life expectancy by being the harbinger of several chronic illnesses like diabetes mellitus, heart disease, hypertension, osteoarthritis and cancers. Apart from causing menstrual disorders, infertility and miscarriages, psychological issues, obesity has been associated with increased risk of almost every complication of pregnancy. Polycystic ovarian syndrome (PCOS) is a common endocrine disorder with a prevalence of about 6–10 % in women of reproductive age.The evaluation in obese patients with PCOS referred should include an endocrinologist evaluation to rule out pituitary or thyroid disease as the cause of anovulation and premature ovarian failure which is characterized by high FSH levels. Other causes of hyperandrogenic state like androgen producing neoplasms, congenital adrenal hyperplasia (high 17-OH progesterone) and Cushings syndrome should be excluded by appropriate evaluation.Endometrial aspiration can be considered in patients above 35 years to rule out endometrial carcinoma. Imaging in the form of ultrasonogram needs to be done to assess the ovaries for polycysts. But it needs to be understood that many PCOS patients may not have cysts and cysts may also be seen in 25 % of healthy women. Sustained weight loss is the only currently available definitive intervention expected to have a lifelong effect on reducing the long-term complications of PCOS. Eventually, any intervention directed at reducing obesity will not only improve the quality of life, but also correct the hyperinsulinism and improve fertility and the lipid and androgen profiles . It has been shown that a modest 5–10 % weight loss can lead to the resumption of ovulation within weeks and improving many features of PCOS. Bariatric surgery is the most effective approach for sustained weight loss in the morbidly obese with effectiveness confirmed in large prospective trials with substantial weight loss and improvements in metabolic effects . Bariatric surgery resulted in improved fertility especially in patients with PCOS where biochemical studies showed normalization of hormones after surgery . Regulation of the menstrual cycle and remission of T2DM occurred immediately, and improvement in hirsutism occurred relatively slowly. In fact >40 % improvement in the menstrual cycle and T2DM was noted within the first month with an approximate 25 % excess weight loss. Obesity increases the risk of both maternal and infant morbidity. Obese women who become pregnant face higher risk of developing gestational diabetes (GDM), pregnancy- induced hypertension, and pre-eclampsia. In obese women complicated by GDM, the pregnancy outcome is definitely compromised regardless of the severity of obesity or the treatment modality. They also have a greater incidence of having preterm labor, higher rates of cesarean sections and perioperative morbidity. Infants born to obese women are also expected to have increased rates of macrosomia and congenital anomalies, as well as life-long complications of obesity associated co-morbidities like T2DM, hypertension etc Obesity poses a significant risk to reproductive-aged women. Weight reduction before conception is the best way to increasing fertility and reduces obesity associated morbidity. When medical interventions fail, bariatric surgery is the most successful method of weight loss, effective increasing fertility and reducing obstetrical complications and maternal and neonatal morbidity comparing obese women. The majority of bariatric surgical procedures are performed in young women. There is a concern about safety and outcomes of pregnancies after weight loss surgery. Pregnancy after weight loss surgery is not only safe, but is associated with more favorable outcomes in comparison to obese populations who do not undergo weight loss surgery. An interval of 2 years is recommended from surgery to pregnancy. This delay helps avoid most of the potential nutritional complications. Optimal patient care is achieved in an experienced, multidisciplinary center. Early involvement of the bariatric surgeon in evaluating abdominal pain is critical because the underlying pathology may relate to the previous weight loss surgery. Although infertility is improved after weight loss surgery, reliable modes of contraception may be limited in this population.

• Weight loss is the key to improvement of PCOS.
• In those with PCOS and infertility artificial reproductive techniques have been more successful after weight loss.
• Bariatric surgery significantly improves all features of PCOS.
• Pregnancy has to be delayed at least from 12 to 18 months after the bariatric surgery
• All the health consequences associated with obesity in pregnancy is diminishes after bariatric surgery however the chance of IUGR has been higher in pregnancies after bariatric surgery necessitating close supervision.
• Regular followup and adequate nutrient supplementation before, during and after pregnancy is important to prevent nutrition related complications.