Ha, this led me to this gem of "original research" in the article on primogeniture:
QUOTE
The term "uterine" implies the woman in whose uterus a fetus developed, which is usually, but not always, the woman whose egg was fertilized to form the embryo. Prior to the 1970s, these were always the same woman, as remains the case for naturally conceived children. However, in cases of surrogacy, in vitro fertilization, and egg donation, it is now possible for a baby born from the uterus of one woman to be the genetic offspring of the egg of another offspring. Therefore, it is now important to distinguish between forms of primogeniture in which inheritance is determined by the woman from whose ovary the egg originated, which could be called "ovarian primogeniture" for clarity, and forms of primogeniture in which inheritance is truly determined uterinely, i.e., by the woman in whose uterus a fetus developed.
The section is titled "Uterine (or ovarian) primogeniture" to reflect the idiosyncratic musings of the feckless author.
Wikipedia, always good for a laugh.