I am not sure if your friend is getting baby blues mixed up with post natal depression, as they are two totally different things. "baby blues" are what alot of people refer to as the few days after your baby is born when your hormone levels "dip" and cause a rush or feelings and possible anxieties. This is completely normal, but it doesnt happen to everyone, I think it is estimated that about 60 percent of new mums experience it. However, it does pass after a few days. Anything longer and more sustained than that needs to be checked as it could be post-natal depression, and as we know this is a serious, but treatable illness.
I also suffer from depression, but didnt have post natal hon. Try not to stress too much about it, but if heaven forbid you do feel it, then make sure you talk to those you love and trust and you will be fine.

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