No principle is as unpopular as "Survival of the Fittest" (even "Collective Toil" is 40/60 versus "Accept Darkness") and I wanted to be able to say exactly why, so me and my buddy Jeff decided to crunch the numbers.
The image above is the top-line summary of some spreadsheet-fu Jeff whipped up to answer the question.
The sheet is public, if you're interested in taking a look.
Long story short, "Survival of the Fittest" takes the natural (i.e. single die) 30% probability of female survivor death and increases it to 51% while "Protect the Young" reduces the probability of that outcome to 9%.