INTRODUCTION: Definition of polyhydramnios is an AFI >24cm on any linear array real time obstetric ultrasound OR Single amniotic fluid pocket more than equal to 8cm on obstetric ultrasound. Polyhydramnios has been long since recognized as known complication of pregnancy. With the advent of ultrasonography, the diagnosis and management of polyhydramnios has been easy and better. AIMS AND OBJECTIVES: To evaluate the various maternal and foetal causes of polyhydramnios and to study the maternal outcome in terms of intrapartum and postpartum complications and foetal outcome in terms of maturity and occurrence of congenital anomalies in pregnancies complicated with polyhydramnios. MATERIAL AND METHODS: The study was conducted in the Department of Obstetrics and Gynaecology, Civil hospital, B.J. medical College, Ahmedabad. It was a prospective observational study of 50 cases of polyhydramnios, carried out between the period of June 2017 to January 2018. RESULTS: In the present study we found that: Incidence of mild polyhydramnios was 72%, moderate was 18% and severe was 10%. Polyhydramnios was idiopathic in 61% of the cases and 31% cases were due to anomalies, PIH was the most common maternal complication followed by preterm labour and malpresentation. Looking at the neonatal outcome 31% had congenital anomalies. CONCLUSION: It is hence concluded that polyhydramnios is a common condition complicating pregnancy. It is mostly an idiopathic condition and among known aetiologies most common is congenital foetal malformations. With increase in severity of polyhydramnios the maternal and perinatal outcomes tend to deteriorate. Each patient with sonographically diagnosed polyhydramnios should be completely investigated for anomalous baby and other possible etiological entities.