What do we know about the cause of postpartum psychosis?

Hormones, especially estrogen, have a significant effect on mood. Estrogen raises serotonin. When estrogen drops precipitously, as it does premenstrually, postpartum, and at the onset of menopause – the brain serotonin levels drop. In women who are sensitive to low serotonin (because of genetics or previous episodes of significant depression) dropping the level will bring on symptoms of depression.

This principle can be demonstrated experimentally. By giving someone a drink of amino acid (from which tryptophan has been removed) the level of brain serotonin will temporarily go down. This is because tryptophan is the amino acid the brain uses to make serotonin. Only people with a vulnerability to becoming clinically depressed will show a depressive response to the serotonin level drop. This phenomenon contributes to premenstrual depression and menopausal (especially perimenopausal) depression.

Think about how dramatically hormone levels drop after child birth. This is why postpartum blues (brief symptoms of mild depression) is extremely common. The postpartum period is the highest risk period for full blown clinical depression.

Post partum psychosis is an extreme form of mood disorder in which underlying genetic vulnerability causes not only depression but a psychotic state. This fortunately only occurs in 1 out of 1000 births.

Psychosis is often confused with delirium. Delirium is a state of severe confusion and disorientation that can be brought on by toxins, severe infections, and many other causes. Every area of functioning is impaired. Psychosis means there is a distortion between conscious reality and external reality.

The most common symptoms of psychosis are hallucinations (seeing things or hearing things that aren’t there) or delusions (beliefs that aren’t true). A person can have one serious delusion that can affect their behavior but can be totally normal in other areas of functioning.

A woman who has had one postpartum psychosis is at a very high risk in any future pregnancies. It was for this reason that Andrea Yates was advised not to have any more children. So why did she and her husband ignore this? I don’t presume to know all the factors that they took into account. But I know she was never diagnosed as bipolar.  And they were never adequately educated about the physiology and medical science that we do have about what causes postpartum depression and psychosis.

Another factor in the Yate’s decision to continue to have children was their faith. They relied more on spiritual experience and counseling with their minister than medical advice. Unfortunately they had come under the influence of an extremist minister, and their medical advice was inadequate and not convincing.

Can they be faulted for not realizing all of this?  I think not. It is not unusual for a person of strong faith to at times feel caught between science on the one side and their faith on the other.

Many centuries ago St. Augustine showed more wisdom in this matter than many of our current experts. He said in effect science and religion aren’t in opposition. They are both ways of looking at and understanding one truth. When science and religion don’t agree we need to discourse and study so that the disagreement can be resolved – without feeling like you have to choose one or the other. Of course not all supposed science is valid and not all ministerial counsel can be trusted. Extremism of any type is dangerous.