The risk of infertility and dietary inflammatory index, a case-control study in Iran

Infertility is defined as the inability to conceive after 12 months of unprotected sexual intercourse and affects 15% of couples globally. Diet influences inflammatory factors, potentially affecting ovarian reserve and thus may have a role in infertility. The present study aimed to assess the association between infertility and the Dietary Inflammatory Index (DII).

This case-control study was conducted at Al-Zahra Hospital, Rasht, Iran, on 123 infertile women and 123 healthy participants. Food intake was assessed using a validated FFQ. The DII was calculated, and logistic regression analysis was performed to assess the relationship between DII and ovarian reserve.

Individuals with a higher DII had a greater risk of infertility compared to those with a lower DII (OR = 2.08, CI 95% = 1.024-4.248, P = 0.043) after adjustment for age, weight, body mass index, intake of anti-inflammatory supplements, suffering from underlying disease, smoking, alcohol consumption, and physical activity. Further adjustments for infertility duration, thyroid disorders, FSH, LH, and number of fertilities did not change the results.

The dietary inflammatory index (DII) was positively associated with infertility. A higher inflammatory diet may increase the likelihood of infertility. Further research is needed to fully understand this connection.