Remarkably, there has been very little detailed research on clinical practice in Russia and its neighbours in what was the USSR, even though it is known that the USSR was isolated from many international developments, in particular evidence-based medicine. In this study we examine obstetric practice, an area of practice where there is an extensive body of evidence on the appropriateness of many interventions. The study is undertaken in Tula, a region 200 km south of Moscow. Building on earlier detailed analyses of data from the facilities in the region, it reports a series of structured interviews with 52 obstetricians from all 19 facilities in the region, designed to identify patterns of prescribing, supplemented by 36 more detailed re-interviews to explore reasons for the differing practices. The study demonstrates a widespread divergence from internationally accepted practice. Maternity care is extremely medicalised but many non-evidence based medicines are used. Some are heavily marketed by large pharmaceutical companies, some were widely used during the Soviet period but never evaluated, and a few are not known to be used anywhere else in the world. For several conditions, the most widely used drugs are clearly inferior to alternative products and some are used for indications quite different from those in other countries. This study contributes to the growing evidence that much of the care provided in Russian maternity units is ineffective or potentially dangerous but also begins to offer some explanations for why this is, including a lack of access to information and a lack of awareness of the concept of evidence-based practice.