There is one clinical trial.
The purpose of this study is to try to understand why the experience of labor differs among women. The investigators want to understand why some women have longer or shorter labors and why the amount of pain women experience is different. The investigators hope to be able to consider women more individually in terms of their pain and progress of labor.
and the investigators also have found that catechol-O-methyltransferase (COMT) rs4633 genotype TT resulted in a slower latent phase rate, and oxytocin receptor rs53576 genotype GG transitioned to active labor earlier .