Well then surely, if Granny fails to ensure that her and Grandpa's fertilized ovum sticks to her uterus, you can call it a natural process, but you ought to treat it! Strain the pee for the life ... it is after all the highest gift in our creation ... and darn well ensure that it is stuck back on the uterine wall where it surely belongs, and where it can form a placenta. To do any less is to allow a vulnerable life to perish (much like allowing a new-born baby to perish by failing to feed it, clothe it, protect it from the elements and predators, etc). Scientific knowledge brings with it responsibility to save life at all costs, no! Pro Life, Anti Culture Of Death, and all that, no! This is surely a natural consequence of your obsession with the single cell, and with equating it to a newborn baby, no!