Monothematic delusion of pregnancy as isolated first-episode psychosis in perimenopause

Dear Editor, Delusion of pregnancy is most often reported in schizophrenia spectrum or mood disorders with psychotic features, frequently accompanied by other delusional themes. A systematic review of 84 cases found schizophrenia as the predominant diagnosis, with antipsychotic-induced hyperprolactinaemia, lactation, metabolic syndrome, and fertility-related psychosocial stressors commonly implicated.[1] Delusion of pregnancy in late life is considered particularly rare, with the Industrial Psychiatry Journal recently describing a 21-year persistent delusion of pregnancy in a 74-year-old woman with affective illness and later persistent delusional disorder.[2] Against this background of chronic and polymorphic presentations, a brief, strictly monothematic delusion of pregnancy as an isolated first-episode psychosis in a perimenopausal, drug-naïve woman has important clinical implications. A 44-year-old married woman from rural India with four grown children and no wish for further offspring developed a 5-month history of fixed pregnancy belief after 2–3 months of missed menstrual cycles during perimenopause. She had no personal or family history of psychiatric or neurological illness, head injury, seizures, or substance use and was premorbidly anxious but well-adjusted. Despite a negative urine pregnancy test, pelvic ultrasonography, and specialist gynaecological examination, she persistently rejected findings and accused her husband of collusion, leading to marital conflict and social withdrawal. She reported distressing subjective abdominal “foetal movements” and embarrassment about “late pregnancy,” but maintained basic self-care with fragmented sleep and anticipatory anxiety; no objective pregnancy-like changes, such as galactorrhoea, abdominal distension, weight gain, or breast changes, were evident. Physical examination showed normal vital signs and body mass inde × 20.4 kg/m², with only mild anaemia (haemoglobin 10.8 g/dL); renal, liver, thyroid functions, fasting glucose, and serum prolactin were normal; pelvic ultrasonography revealed a simple ovarian cyst without gestation. Mental status examination demonstrated alertness, intact orientation, anxious, perplexed affect, and a strictly monothematic, unshakeable pregnancy belief without hallucinations, first-rank symptoms, formal thought disorder, or cognitive impairment. She fulfilled DSM-5[3] criteria for somatic-type delusional disorder, representing an isolated first-episode psychosis. The patient was treated with olanzapine 10 mg/day, fluoxetine 20 mg/day, and etizolam 0.5 mg/day. At one-month follow-up, there was almost complete resolution of the delusional belief with normalization of sleep and anxiety, and restoration of premorbid functioning, contrasting sharply with the 21-year chronic course reported in the elderly case.[2] This case distinguishes delusional pregnancy from pseudocyesis, wherein objective pregnancy-like somatic changes (abdominal distension, breast enlargement, amenorrhoea, weight gain) and wish-fulfilment dynamics, predominate rather than an isolated psychotic belief.[4-6] The perimenopausal onset, drug-naïve status, normal endocrine profile, absence of fertility stress, and embarrassment rather than desire for pregnancy suggest that oestrogen withdrawal and neuroendocrine instability may precipitate monothematic psychosis in vulnerable women, distinct from chronic late-life presentations and pseudocyesis.[1,2,4,5] In occupational and general hospital settings, clinicians encountering pregnancy beliefs in perimenopausal women with negative obstetric workup should consider somatic-type delusional disorder and initiate early low-dose antipsychotic treatment, as drug-naïve, first-episode presentations may remit rapidly with excellent functional outcome. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Authors contributions Concept and design of paper: SK, MZ, AA, SC. Data acquisition: SK, MZ, AA. Drafting the article and revising it critically for important intellectual content: SK, MZ, AA. Final editing and approval of the version to be published: SK, MZ, AA, SC. This manuscript has been read and approved by all the authors. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.