The term I would use for such a woman, Mr. Scott, is "privileged." She's privileged because her husband evidently earns enough that she can afford not to work. She may be making a good choice and she may be making an ignorant one depending on how whether she lives in a common law state or a community property state. The common law system provides that property acquired by one member of a married couple is owned completely and solely by that person. Marital property in community property states are owned by both spouses equally (50/50).  
'Natural selection' is the process whereby organisms better adapted to their environment tend to survive and produce more offspring. It is not the opposite of the concept of family planning.  Women have the right to make medical decisions for themselves. I assert that to think otherwise is backward and potentially quite dangerous.