Farnaz Shahdadian - MSc. Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
Reza Ghiasvand - Ph.D. Associate Professor of Nutrition. Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
Behnood Abbasi - Ph.D. Assistant Professor of Nutrition. Department of nutrition, School of Medical Sciences, Islamic Azad University, Science and Research Branch, Tehran, Iran.
Awat Feizi - Ph.D. Associate Professor of Biostatistics, Department of Biostatistics and Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran

Background and Aim: Polycystic ovary syndrome (PCOS) is a multifactorial endocrine disorder in women. Change in lifestyle, especially dietary pattern, might have a role in prevalence of PCOS. The limited number of studies has made it difficult to draw any conclusion about the dietary patterns with PCOS. This study aimed to investigate the association between dietary patterns with PCOS.Methods: This case-control study was performed on 225 new diagnosed patients and 345 healthy women in Isfahan, Iran. The presence of PCOS was confirmed by the expert gynecologists based on Rotterdam criteria. Usual dietary intake was assessed by a 168-items food frequency questionnaire. Dietary patterns were identified by principal component analysis.Results: Three major dietary patterns including western, plant-based, and mixed were identified that explained 53.93% of the variance of food intake. Top tertile of western dietary pattern significantly increased the odds of PCOS (OR, 2.03; 95%CI, 1.12-3.67), either before or after adjustments for covariates. After adjustments for potential confounders, the highest tertile of plant-based dietary pattern was related to higher odds of PCOS than the lowest one (OR, 2.32; 95%CI, 1.23-4.37). In addition, those in the second tertile of mixed dietary pattern were 66% less likely to have PCOS compared with the lowest one (OR, 0.34; 95%CI, 0.18-0.61).Conclusion: We found that western and plant-based dietary patterns were associated with an increased risk of PCOS. Also, moderate adherence to the mixed dietary pattern was associated with reduced risk of PCOS. To confirm our findings more studies with longitudinal design are required.

Dietary pattern; Polycystic ovary syndrome; Factor analysis