Preterm birth (delivery < 37 weeks of gestation) is an important risk factor for the later development of hypertension and chronic kidney disease. The exact cause of this association is unknown, but likely relates to impaired kidney development in early life. We have previously shown that preterm birth can result in the formation of glomeruli with shrunken capillary tufts in the kidneys of human preterm neonates. We have also shown, in lambs, that preterm birth and/or postnatal mechanical ventilation lead to substantial reductions in glomerular capillary length and filtration surface area at 3 days after birth. If this persists, it has the potential to cause glomerulosclerosis and renal dysfunction. Therefore, in this study we aimed to determine the long-term impact of preterm birth on glomerular morphology in adult sheep. Singleton male sheep were delivered moderately preterm at 132 days (~0.9) of gestation or at term (146 days of gestation). The ewes assigned to deliver preterm were administered 11.4mg betamethasone at 48 and 24 hours prior to birth, and the preterm sheep did not require mechanical ventilation postnatally. After weaning, the Preterm (n=6) and Term (n=6) sheep were maintained in natural grass paddocks and were euthanised at 14.5 months of age (early adulthood). The right kidney from each sheep was perfusion-fixed, and stereological methods were used to determine mean renal corpuscle and glomerular volumes, and glomerular capillary length and surface area in the outer, mid, and inner regions of the renal cortex. Glomerulosclerosis, and interstitial collagen levels in the medulla and cortex, were assessed histologically. Sheep born preterm were on average 2.5 kg lighter at birth than those born at term (p=0.0001), but at 14.5 months of age there was no difference between the Term and Preterm sheep in body or kidney weight (Term: 128 ± 8 g, Preterm: 121 ± 5 g, p=0.45). Renal corpuscle volume was significantly (p=0.03) larger in the Preterm sheep than the Term sheep (e.g. mean for inner cortex – Term: 0.0018 ± 0.0001 mm3, Preterm: 0.0024 ± 0.0003 mm3) with the Preterm sheep exhibiting enlarged Bowman’s spaces; however, there was no difference in glomerular volume between groups. Similarly, preterm birth did not impact mean glomerular capillary length or surface area per glomerulus in adult sheep. There was also no difference between groups in interstitial collagen levels, or glomerulosclerosis index. Although there is some evidence of morphological changes in the kidneys following preterm birth, findings suggest that moderate preterm birth per se does not adversely affect total renal filtration surface area or result in renal disease in early adulthood. It is now important to determine whether glomerular capillarisation is similarly normalised in preterm-born adults that were exposed to mechanical ventilation in the neonatal period.