1. Is this milk stored in glass or plastic? off smells from plastic are
common, especially after freezing for some time.

2. This sounds to me as if enzymatic breakdown of fats into free fatty
acids is liberating some smells the mother deems noxious, but which could
be within the range of normal. Rancidity occurs with oxidation.  All milk
smells of maternal diet and tastes of it too. What's the fat intake of this
mother like? Quantity and quality? I'd ask someone like Prof Margit Hamosh,
a lipid biochemist, to comment here. In fact I've just asked Bob Gibson,
lipid biochemist extraordinaire (the RA Gibson of the studies showing
auditory and visual acuity to be better in breastfed infants, linked with
LC PUFAs in breastmilk).Will let the list know if he adds anything to this.

Key test for me would be whether the baby drinks the stuff and with what
results. If the kid turns up his nose at it, I'd worry about it. If not, it
may well be normal for her. As described, it's highly unlikely to harm the
baby.

3.If it isn't that, and it's a rotten rather than sour smell, one would
have to wonder about bacterial contamination. But the likelihood is very
low, given the bacteriostatic and bacteriocidal properties of breastmilk in
these conditions.

As for Vitamin K: I have a whole chapter on this just waiting to get
organised into my next book. It's not easy to summarise it briefly, but if
I were a mother well-fed in pregnancy, had a baby that was thriving and
growing fat on breastmilk alone, and was not ingesting hepatotoxic
compounds, I would not be worried about vitamin K, injections or oral. The
history of this controversy reveals its environmentally induced or
iatrogenic nature. Which is not to say that we should all stop using
vitamin K instantly, just that we should take a good hard look at the
matter and identify the fraction of infants at risk and treat them, not
medicate the whole population. Wait till the chapter is done:I really can't
write more on this now.

Maureen Minchin