To study the relationship between on-farm welfare and reproductive performance in the sow, the TGI 35L Animal Needs Index was modified for use in Finnish pig production. The modified index had a maximal total score of 100. It was comprised of six categories: 'locomotion' (maximal score 21 for dry sows and 11 for lactating sows), 'social interaction' (12/8), 'floor quality' (16/9), 'stable climate' (16/21), 'feeding' (16/23) and 'health and stockmanship' (19/29). Index scorings were performed separately in farrowing, breeding and gestation units on 28 representative Finnish sow farms. One-year production parameters were collected. Multiple linear regression was used for statistical analysis. Total ANI-points varied between 36.5-68.0 for lactating and 39.5-86.0 for dry sows. Litter size increased with increasing scores for 'feeding' in the dry sow unit. Controlling for breed, high scores for 'health and stockmanship' and 'floor quality' shortened the reproductive cycle, probably because of good leg health. The number of weaned piglets per sow per year (PSY) increased with increasing scores for dry sow 'health and stockmanship', 'floor quality' and an interaction of 'feeding' in the farrowing and mating units. PSY increased with decreasing scores for farrowing pen 'climate'. High-quality floors and stockmanship appear to correlate positively with reproductive performance in the sow. Effects of a welfare-promoting feeding strategy on reproduction are contradictory.