There has already been talk this year about whether there is a fatherhood penalty and the fact that mothers effectively pay to return to work but recent research has now compared working mothers against other working women. That research concludes that mothers earn about 3% less per hour for each child they have compared to childless women in the same role. 

This is an interesting observation. As it stands, mothers have very few avenues to challenge this type of practice as an equal pay or sex discrimination claim would only be of relevance if they are comparing themselves against a man (not another woman). 

Further, much of the recent focus on rebalancing pay and opportunities for mothers has been on the gap between working mothers and men (for example, the new gender pay reporting requirements). In light of this research, will there be shift to look specifically at mothers against the rest of the workforce generally?