Jeanne:  Although a mother who goes through early menopause due to surgery
is at greater risk for osteoporosis, it is due to the longer period of
time that she spends in the postmenopausal state, i.e. a longer time for
her bones to be deprived of estrogen as compared with the average
menopausal woman, who starts the process on average about 10 years later.
So in looking at this woman's overall risk for osteoporosis, breastfeeding
for 6-12 months or even 2-3 years is not likely to seriously affect her
risk.  As usual, we have to look at the overall risk, to her and to her
baby, of artificial feeding.  In my opinion, she should breastfeed first,
then take the estrogen.
As for hysterectomy, that is certainly not required prophylactically as
this doctor's suggestion implies.  Instead, estrogen is prescribed
together with progestogen to protect the uterus from cancer.  Hope this
helps, Alicia Dermer, MD, IBCLC, in Central New Jersey.