Background: There has been conflicting data regarding the relationship between obesity and progression free survival in patients with ovarian cancer. There has been some evidence to suggest that obesity results in altered tumor biology and a poorer prognosis in these patients. The aim of this study was to examine whether obesity is a risk factor for time to recurrence in primary epithelial ovarian cancer. Methods: A multicenter retrospective chart review was performed at Mercy Medical Center and University of Michigan Medical Center. 591 patients were diagnosed with primary epithelial ovarian cancer between 2004-2009. However, 221 patients were excluded from the analysis because of persistent or progressive disease, treatment with neoadjuvant chemotherapy, presence of synchronous tumors or incomplete follow-up data. 370 patients were eligible for analysis. Data collected included: height and weight at the time of surgery, age, race, medical co-morbid illnesses, tumor stage, grade and histology. Treatment related data such as number of cycles of adjuvant chemotherapy; and optimal versus suboptimal tumor debulking was also collected. Body mass index (BMI) was defined according to WHO 2004 criteria. Women with a BMI greater than 30 were categorized as obese. The diagnosis of recurrence was made by positive radiological or pathological diagnosis of cancer recurrence after patient had surgery, received adjuvant chemotherapy and had no clinical, radiological or serological evidence of recurrence during this time. The time to recurrence was then quantified in terms of months from the initial surgery. Survival analyses were performed with the Kaplan-Meier method and compared using log-rank testing. Time to recurrence was analyzed using Mann-Whitney U and Wilcox W tests. Results: 130 (35%) obese patients were compared with 240 (65%) non obese patients. A recurrence was documented in 125 (47.9%) non obese patients and 49 (37.7%) obese patients. Time to recurrence between both BMI groups was found to be identical, at 15 months (p=1.0). The progression free survival was similar in both obese and non obese subjects (p=0.118). Conclusions: Obesity does not impact the time to recurrence in patients with primary ovarian cancer.