There is a small but fascinating medical literature on delusional pregnancy that reports cases of people who, in the context of psychotic mental illness, come to believe they are expecting a child. Interestingly, the cases are not solely women of child bearing age – delusional pregnancy has also been reported in men and the elderly.
In fact, almost as many cases of delusional pregnancy have been reported in men as in women. Unfortunately, no studies have been done on how common this delusion is or what it is associated with, so it’s not clear whether men are equally as likely to have a delusions of pregnancy, or whether it’s just because these cases seem more unusual and is more likely to be published.
Below is one of the cases from a classic 1994 article on delusion of pregnancy from The British Journal of Psychiatry:
B was a 39-year-old, single, female schizophrenic patient with treatment-resistant psychotic symptoms including delusions of pregnancy of 20 years’ duration and amenorrhoea for the previous 18 years. On examination she was convinced that she had a triplet pregnancy – two boys and a girl – of four months gestational age. She reported that they moved about inside her abdomen and also talked to her.
When she was 19, her dancing partner kissed her and she believed that he had been repeatedly impregnating her by means of the same kiss. Regarding her previous pregnancies she believed that their father did not want her to deliver them and hence he ‘withdrew’ them. She did not have any physical symptoms of pregnancy other than amenorrhoea and attributed this to the ‘supernatural nature’ of the pregnancy.
In a curious twist, a recent article reported on a patient who had the delusional denial of pregnancy – where she was clearly heavily pregnant but had the delusion that she was not.
It’s important to note that these cases are not the same as ‘phantom pregnancies’, something medically named pseudocyesis, where a women can show the signs of expecting a child (swollen breasts, enlarged abdomen etc) without actually being pregnant.
This is not a delusion, as the patient can be well aware that they are not actually pregnant or will accept the possibility that they are not when the results of medical tests come though.
Indeed, ‘phantom pregnancy’ can be due to clear disturbance to the hormones – one case was due to a brain tumour that disrupted the endocrine system – but other cases seem to be related to the strong desire to be pregnant.
However, even this has its male equivalent. Couvade syndrome is where men experience some of the physical effects of pregnancy (morning sickness, aches, weight gain) in response to their partner’s pregnancy.
Link to classic 1994 paper on delusion of pregnancy.

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