If a woman needs a hysterectomy is it better to leave the ovaries and if so why?

It's better, otherwise you go straight into menopause. I had a hyster when I was 27. The plan was to take everything, except one ovary, that way I could still produce Estrogen, and not be menopausal. Didn't work out that way, so I was hot flashing prior to leaving the hospital. Did hormone replacement for several years, adjusting the dosage in the beginning, because it was either too much/too little, bad,bad headaches with Estrogen. Now, I take Estroven, over the counter. Sometimes, I hit the health food aisle, and get Black Cohosh, it works great with hot flasher/night sweats, irritability. WalMart's version is called Estrablend, half the price of the Estroven.