I had a great start with 3 women and 2 men, but strangely the first 4 babies born were boys. At this point I'm a bit concerned, because my females are all over 40 and my males are getting closed to 50. When's the end of "breeding"?

I did get two girls finally, but there's still a 10 year gap with boys/girls. I'm hoping it won't cause problems.