25% of women suffer some form of depression after child birth. From the ‘baby blues’, to post natal depression (PND), to post natal psychosis (PNP), which can result in infanticide and suicide. Luckily PNP only occurs in 0.05% of women. The depression is caused by the rapid drop in progesterone levels after the expulsion of the placenta. Serotonin levels drop too. Anti-depressants are not required, what is are large amounts of progesterone. From 800mg/day for PND up to 2400mg/day for post natal psychosis, the amounts Dr Katherina Dalton found effective.