Puerperal psychosis
This is a serious condition that affects around 1 in 500 women and starts within days or weeks of childbirth. It can develop in a few hours and can be life-threatening, so needs urgent treatment. Other people will usually notice it first. You start to say strange things and become excitable and unpredictable. You may have rapid mood swings, strange or bizarre beliefs and may hear voices. This always needs medical help and support. You may have to go into hospital, but your baby should go with you.
It is more likely to happen if you, or someone in your family has had PND, or bipolar disprder (manic depression). Let your doctor or midwife know about this so you can have treatment to reduce the risk of it happening. Although puerperal psychosis is a serious condition, full recovery is possible with the proper treatment.
Ref : RCP