I'm going to do a little shouting but read joyous note into it.

Breastfeeding causes osteoporosis later in life?   NO, NO, NO, NO, NO !
It does the OPPOSITE.
It gives FANTastic protection.  Levels of calcium in the bones do fall while
breastfeeding, BUT your bone mineralisation is BOOSTed and by 6 months after
weaning, your calcium levels are HIGHER than they would be if you had not
breastfed at all.  This then goes to hip fractures too.  From one study women
who had never breastfed had TWICE THE RISK of hip fractures than those who had
breastfed.  The LONGER the woman breastfeeds, the GREATER the PROTECTION.
Breastfeeding for longer than 9 months for each child can REDUCE your risk to
ONE QUARTER of that for non-breastfeeders.  Think of the deaths this would
save and the health care costs of osteoporosis and all its problems,  hip
fractures are often the beginning of the end of life for thousands upon
thousands of women.

Look at  Cumming & Klineberg 1993, Intl J Epidemiol. 22:684-91  This is an
Australian study.

I've now taken off my Town Crier's Cloak and put down the bell.
Yours, Helen Woodman, National Childbirth Trust Breastfeeding Counsellor.