I'm not sure if you've seen this but it is an important aspect to consider:
I have read that females, generally, tend to have about 75% of the lower body strength of a man and 50% of the upper body strength of a man; that could, of course, relate to those that don't lift and train and progress, since we know that some female powerlifters are stronger than the average Joe etc.
With really lightweight females, BW of 125 lb (for example) a barbell alone (44 lb) is a good percentage of bodyweight being moved, and since most females are supposed to have lower bodyweights than their male counterparts, it's something to take in to consideration.
Increases in weightloads moved are a lot smaller incrementally; when I do deadlifts, and have done my warm-up, if I put 10kg increments on, I find it a struggle (I really notice that leap), whereas if I put 5kg increments on the bar and do less reps but more sets, I can get to the higher numbers that I want to reach without having felt like I just took a leap over a massive Gorge. When I hit my topmost lift, I then tend to add even smaller increments to the bar.
The info may be of some use, or give food for thought.