Genetics

Phenotyping is key in all genetic association studies and designing clinical studies to assess the genetic contribution to pain and analgesic response in general, and in the context of obstetric pain is even more challenging. In addition, interpreting results, particularly when multiple genes are evaluated, requires large sample sizes and appropriate statistical analysis to avoid misconstrued finding. The genetic contribution to labour pain or even that of pharmacogenetics to explain differences in analgesic response is probably not simple and straightforward and we are at the beginning of our explorations. Firm recommendations to tailor opioid regimens based on patients’ individual genetic profile are not available and are unlikely to become available in the near future other than for the prescription of codeine. To help explore genetic variants that influence the progress of labour and other various obstetric outcomes, the concept of mathematical modelling of labour progress is extremely promising and may in the future allow identification of some important genetic contributions and will perhaps one day predict labour outcome and labour pain perception.