What to watch with HbA1c and fertility?

HbA1c reflects average blood glucose over 2–3 months. Elevated levels (≥5.7% prediabetes, ≥6.5% diabetes) are linked to fertility issues: in women, they may indicate insulin resistance or PCOS disrupting ovulation; in men, they impair sperm quality (motility, DNA fragmentation). A normal HbA1c (<5.7%) is favorable but not a standalone fertility predictor. Caveats: HbA1c does not capture short-term glucose spikes and can be skewed by anemia or hemoglobin variants. For fertility planning, combine HbA1c with fasting glucose and oral glucose tolerance test. Lifestyle interventions (diet, exercise) can lower HbA1c and potentially improve fertility outcomes. Evidence: human-observational, moderate.