Postnatal depression which persists beyond six months after birth and is severe, increases the risk of children exhibiting behavioural problems, achieving lower GCSE mathematics grades at 16 years and having depression at 18 years of age.
Postnatal depression which is persistent (whether moderate or severe) increases mothers’ risk of continuing to experience depressive symptoms beyond the postnatal year, with high levels found up until 11 years after childbirth.