Polycystic ovary syndrome (PCOS), one of the most common endocrine disorders in reproductive‐aged women, is associated with metabolic disturbances. The present study aimed to examine changes in body weight (BW) and glucose and insulin tolerance in a prenatally‐androgenized (PNA) rat model of PCOS compared to control with increasing age. Pregnant rats in the experimental group were subcutaneously injected with 5 mg of free testosterone on the 20th day of pregnancy, while the control group received the solvent. Female offspring of both groups, PNA rats (rat model of PCOS) and control, were examined in terms of changes in BW, glucose and insulin tolerance at 3, 6, 12 and 20 months of age. BW at birth (6.53 ± 0.89 vs. 5.60 ± 1.18 g; P = 0.038), 15 (25 ± 1.15 vs. 22.36 ± 3.98 g; P = 0.019) and 30 (59.37 ± 10.19 vs.49.9 ± 9.39 g; P = 0.022) days of age was significantly increased in the rat model of PCOS compared to control, but no significant differences were observed in BW of the rat model of PCOS compared to control at 60 (P = 0.155) and 75 (P = 0.932) days or at 3 (P = 0.239), 6 (P = 0.782), 12 (P = 0.755) and 20 (P = 0.092) months of age. Rat model of PCOS showed impaired glucose tolerance (IGT) at 3 months of age (P = 0.020) and insulin resistance (IR) with increasing age (3–20 months of age) compared to control. Increased BW before puberty, IGT at 3 months of age and IR with increasing age were observed in our rat model of PCOS. This rat model may contribute to a better understanding of underlying mechanisms of changes in BW, IGT and IR in future studies.