While I agree with you Bags that being a SATH mother is just as important work as working outside the home, and an important part of our own personal development, at the time it certainly didn't feel like it. I remember feeling quite deflated and lacking confidence at that time of my life (30-37) and like others, my professional life took off in my forties and my confidence grew with it.
I started my own practice when I was 45 in a deprived area of North Tyneside, and asked advice from as many people as I could. One man expressed reservations about how my potential patients would react to having a woman in their midst, implying that they would prefer a man. Then he asked how old I was, and said 'oh if you're that old you'll probably be alright, but they wouldn't trust a younger woman.' So older women were seen as more competent and mature, not past it.
I think women who are 39 now are in a different place from many of us at that age, with many of them having only just started their families, rather than having mostly completed them.
I also think that it is their generation, not ours, which is fixated on appearance and sexual attractiveness in a way which makes our era look like one of innocence.