Objectives To examine the association between doctors’ sex and receiving sanctions on their medical registration, while controlling for other potentially confounding variables.

Design Cross-sectional study.

Setting The General Medical Council (GMC)'s List of Registered Medical Practitioners (LRMP) database of doctors practising in the UK.

Population All doctors on the GMC's LRMP on 29 May 2013. The database included all doctors who are or have been registered to practise medicine in the UK since October 2005. The exposure of interest was doctor's sex. Confounding variables included years since primary medical qualification, world region of primary medical qualification and specialty.

Outcome measures Sanctions on a doctor's medical registration. Sanction types included warnings, undertakings, conditions, suspension or erasure from the register. Binary logistic regression modelling, controlling for confounders, described the association between the doctor's sex and sanctions on a doctor's medical registration.

Results Of the 329 542 doctors on the LRMP, 2697 (0.8%) had sanctions against their registration, 516 (19.1%) of whom were female. In the fully adjusted model, female doctors had nearly a third of the odds (OR: 0.37, 95% CI: 0.33 to 0.41) of having sanctions compared to male doctors. There was evidence that the association varies with specialty, with female doctors who had specialised as general practitioners being the least likely to receive sanctions compared with their male colleagues (OR: 0.26, 95% CI: 0.22 to 0.31).

Conclusions Female doctors have reduced odds of receiving sanctions on their medical registration when compared with their male colleagues. This association remained after adjustment for the confounding factors. These results are representative of all doctors registered to practise in the UK. Further exploration of why doctors’ sex may impact their professional performance is underway.