Menopause

I happened to come across one article in The Star paper yesterday on the title above. It mentioned that women will only experience menopause at the average age of 50-51 years old. As far as I know, my understanding of menopause is simply when the monthly period for women comes to a stop. I got 2 curiousity here which I need your valuable comments,

Firstly, when women come to menopause, will they still enjoy normal intercourse & sex life? And why there will be mood swing?

Secondly, in the article it said 75% of pregnancy after the age of 40 is not plan. Why is it so? Why women are afraid to get pregnant after the age of 40? Any special reason? And even menopause, can a women get pregnant via in-vitro way? Meaning bayi tabung uji.

Please comment, thanks.