Delusion of Pregnancy: An Updated Systematic Review

Delusion of pregnancy (DoP) is a rare psychopathological symptom characterised by the fixed, delusional conviction of being pregnant in the absence of objective evidence. The systematic review by Bera and Sarkar remains, to this day, the principal quantitative reference on the phenomenon, based on 84 cases published up to August 2014. The aim of the present work is to update this case series by including literature published between September 2014 and August 2026, and to analyse any clinical and aetiological differences that emerge relative to the original sample. Thirty-two new cases were identified from 18 publications, extracted using the same categorical grid employed in the original study and integrated with the 84 historical cases (combined sample, n = 116). All comparisons between the original and updated subsamples reported below are descriptive and exploratory; no inferential statistical testing was performed, and the reported percentages should not be interpreted as validated effect sizes. The general profile of the disorder—female predominance, schizophrenia as the most frequent underlying diagnosis, monofetal presentation, good overall treatment response—is substantially confirmed. The most marked differences between the two subsamples concern a higher proportion, among recently published cases, of organic/geriatric presentations (28.1% vs. 4.8%) and coenaesthopathic processes (43.8% vs. 20.2%); however, sensitivity analysis indicated that both differences are substantially attenuated (to 14.8% and 33.3%, respectively) once a single five-case series is excluded, suggesting that publication-level clustering, rather than a genuine population-level temporal trend, plausibly accounts for much of this apparent shift. The data suggest, on an exploratory basis, the clinical usefulness of distinguishing a primary form, of complex delusional origin, from a secondary form due to somatic misinterpretation—a distinction presented here as a hypothesis-generating proposal, not as a validated clinical typology, with potential implications for the diagnostic assessment pathway and for pharmacological and psychotherapeutic treatment approaches, to be confirmed through prospective, controlled study designs.