Overview
- The Human Reproduction study released Tuesday reports that men who ate more ultra-processed foods had higher odds of subfertility and longer time to pregnancy, while women with higher intake had slightly smaller embryos and yolk sacs at seven weeks.
- Researchers tracked 831 women and 651 male partners in the Netherlands from 2017 to 2021, using early‑pregnancy food questionnaires and transvaginal ultrasounds to measure embryo size and yolk sac volume.
- A separate U.S. analysis of NHANES data, published Monday in Nutrition and Health, found that higher ultra-processed food intake was linked to lower odds of being classified as fertile among women, and the apparent benefit of a Mediterranean-style diet weakened after accounting for obesity.
- Scientists caution that both papers show associations rather than causation and point to plausible pathways such as fewer key nutrients in these foods, hormone‑disrupting chemicals from packaging, chronic inflammation, and shifts in the gut microbiome.
- Clinicians may widen preconception advice to include both partners and small, practical swaps that cut packaged snacks, sugary drinks, processed meats, and ready meals, though experts urge care to avoid blame and to focus on overall healthy habits.