Check out this interesting graph from the Lord of the Rings project that divides the population of Middle Earth into race and gender.
It was put together from the characters that feature in Lord of the Rings, The Hobbit and some of Tolkien’s posthumously published works including Silmarillion.
As you can see, men far outweighed the women in Middle Earth making up 81% of the characters described by J.R.R Tolkien. This is not to suggest that the population of Middle Earth was somehow oddly predisposed to bear male children, but rather that the majority of Tolkien’s protagonists were male. It makes sense I suppose, considering much of what he wrote about were epic battles and wars.
Source: LoTR Project