Serial Mom, besides the John Waters movie starring Kathleen Turner, is a term where a woman immediately seeks to become pregnant soon after giving birth as soon as possible. They feel that their lives are meant for having children, even when they're having issues with income and keeping the kids they have clothed and fed. The women can be married or single, and may inform their significant other that they are on birth control when they are not.
I've known two women who were like this. One was married to a husband she never saw because he worked multiple jobs, although they had to see each other at least once every ten months to conceive another child. The other was on welfare and had a different father for each of her nine kids. For some of her children she didn't even know the name of their father. She felt a biological urge to remain pregnant because she felt like someone wanted and was depending on her. While I'm not sure what this would fall under in the DSM-V, it must certainly be part of several mental health issues that may be treated with therapy and/or medication.
There are also some religions that promote very large families, several which have had their own television shows.
Iron Noder 2017