Aim of study: To evaluate tubal patency in repeat breeder Holstein cows with the purpose of estimating the frequency of oviduct obstruction as a cause of the repeat breeding syndrome. Area of study: Lugo (NW Spain) Material and methods: In 50 repeat breeding cows, a solution of the dye phenol-sulphon-phthalein (PSP) was instilled into one uterine horn with the aid of a balloon catheter. Urine was collected 15, 25 and 45 min post-PSP infusion. Urine of a reddish color was used as indicator of tubal patency, as the PSP had passed across the oviduct into the abdominal cavity and was eliminated in urine. The other oviduct was evaluated on a different day. Main results: Of the 50 cows tested, 44% had some degree of oviduct obstruction: 4% had bilateral oviduct occlusion, 20% unilateral oviduct occlusion, 16% bilateral oviduct stenosis and 4% unilateral oviduct stenosis. No significant relationship could be established between tubal impermeability and postpartum reproductive or metabolic diseases. Research highlights: Tubal stenosis or occlusions were frequent and they are likely to contribute to the repeat breeding syndrome in dairy cows; thus, tubal patency should be routinely evaluated in repeat breeders. The PSP test is easy to perform, well tolerated by animals, and allows evaluating both oviducts separately. Xunta de Galicia, Spain: Programme for consolidating and structuring competitive research groups: GRC2015/003. Xunta de Galicia, Spain: Project ‘RUMIGAL: Rede de estudo multidisciplinar dos ruminantes en Galicia R2014/005 SI