There is no definitive answer to this question as doulas' earnings can vary greatly depending on a number of factors, such as their experience level, the services they offer, the geographical region they work in and the clientele they serve. However, some doulas may be able to earn more money than others by specializing in certain areas or offering unique services. For example, those who work with high-risk pregnancies or provide postpartum support may be able to command higher fees than those who only provide labor support. Additionally, doulas who are certified lactation consultants or have other credentials may also be able to charge more for their services.