We often discuss the importance of choosing organic fruits and vegetables when possible to minimize pesticide exposure with the idea that pesticide exposure may negatively impact fertility and a developing baby. Animal studies have shown that ingestion of pesticides reduces litter size. Until now the studies in humans were limited to studies of women with occupational pesticide exposure or those who lived in or near agricultural areas. In these studies, pesticide exposure was linked to increased risk for infertility and adverse pregnancy outcomes. A new study published in October 2017 looked specifically at women going through fertility treatments to determine the impact of pesticide exposure from dietary fruits and vegetables on pregnancy and live birth rates.
A group of 325 women underwent 541 ART (assisted reproductive technology) cycles. Prior to initiation of fertility treatment, the women filled out a food frequency questionnaire to assess their intake of specific fruits and vegetables. Each fruit and vegetable was assigned a scored based on the pesticide residues from US Department of Agriculture data. Intake of organic versus conventional fruits and vegetables was also assessed.
Here were the results. Total fruit and vegetable intake was unrelated to probability of implantation, clinical pregnancy, or live birth. Women with highest intakes of high pesticide residue fruits and vegetables (≥ 2.3 servings/day) had an 18% lower likelihood of clinical pregnancy and 26% lower likelihood of live birth compared to women with the lowest intakes of high pesticide fruits and vegetables (<1 serving per day). High pesticide residue fruit and vegetable intake was also associated with increased risk of pregnancy loss. Higher intakes of low pesticide residue fruits and vegetables intake were associated with lower risk for early pregnancy loss. The authors then used a model to estimate the impact of replacing high pesticide fruits and vegetables with low pesticide fruits and vegetables. Based on this model, replacing 1 serving per day of high pesticide fruits and vegetables with 1 serving of low pesticide fruits and vegetables would result in a 79% higher odds of clinical pregnancy and 88% higher odds of live birth. The possible mechanisms for the effect of pesticide exposure of pregnancy and live birth rates include the possibility that pesticide exposure may cause placental dysfunction induced by oxidative stress, and/or may cause decreased cell division, cell death, and/or impaired implantation.
The bottom line is, according to these results, higher intake of pesticides from fruits and vegetables may reduce the likelihood of having a live birth when undergoing fertility treatment. Taking steps to reduce your pesticide exposure from fruits and vegetables in your diet is a helpful step to optimizing your chances of success and a healthy pregnancy. How can you reduce your pesticide exposure from fruits and vegetables? Choose organic when possible. When you’re choosing which fruits and vegetables to buy organic, the Dirty Dozen are the highest priority to buy organic, while the Clean 15 tend to be lower in pesticide residues, so they aren’t as high priority to buy organic versions. Check out the Environmental Working Group’s Guide to Pesticides in Produce to view the Dirty Dozen and Clean 15 lists and for more information.
Reference: Chiu Y, Williams PL, Gillman MW. Association between pesticide residue intake from consumption of fruits and vegetables and pregnancy outcomes among women undergoing fertility treatment with assisted reproductive technology. JAMA. 2017.