Dietary Patterns in Relation to Ovulatory Infertility: A Case-Control Study

Headnote

Keywords: Dietary Pattern, Nutrition, Infertility, Polycystic Ovarian Syndrome

Background: Previous studies have focused on a single or few dietary nutrients, and scarce data is available on dietary patterns related to infertility. Therefore, we aimed to investigate the relation between female ovulatory infertility and major dietary patterns among women attending fertility clinics.

Materials and Methods: This case-control study was conducted on 167 infertile women with PCOS and 251 controls. PCOS was determined by using 2003 Rotterdam criteria. Usual dietary intake was assessed using a validated 168-item semi-quantitative food frequency questionnaire. Major dietary patterns were identified using factor analysis.

Results: Two main dietary patterns, healthy dietary pattern and western dietary pattern, were identified. Healthy dietary pattern was high in green leafy vegetables, fruits, low fat dairy products, nuts, fish, poultry, vegetable oils and whole grains and the Western dietary pattern was high in red meat, processed meats, refined grain, French fries, high fat dairy products, snacks, starchy sweets, softdrinks and hydrogenated fats. Cases were statistically more overweight and abdominally fat than controls (P=0.00). No statistical significant difference was seen in total energy intake, nutrient intakes and dietary fiber between the two groups. Lower adherence to western dietary pattern was associated with decreased chance of infertility (OR=0.61; 95% CI: 0.41-0.91, P=0.01). The association remained significant even after taking other confounders into account (OR=0.62, 95%CI: 0.41-0.96, P=0.03). However, after adjusting for energy and macronutrient intakes, the association altered to marginally significant relation (P=0.07). Associations between having healthy dietary pattern and infertility regarding PCOS was not statistically significant (P=0.45).

Conclusion: Lower adherence to western dietary pattern may protect women in reproductive age against infertility. Further studies are needed to confirm the role of different dietary patterns on fertility outcomes.