Brockington (Reference Brockington2016) highlights the co-occurrence of eclampsia and postpartum psychosis as an important diagnostic consideration. We agree and have described in our previous work the importance of performing thorough physical, neurological and laboratory examinations of every patient with first-onset postpartum psychosis as this might lead to a diagnosis with treatable causes and co-morbidities (Bergink et al. Reference Bergink, Burgerhout, Koorengevel, Kamperman, Hoogendijk, Lambregtse-van den Berg and Kushner2015b ). In addition to eclampsia, clinicians should consider the postpartum occurrence of autoimmune disorders (e.g. thyroiditis), encephalitis (e.g. NMDA encephalitis), infections (e.g. endometritis, mastitis) and rare inborn errors of metabolism.

Most women with first-onset postpartum psychosis will exhibit one of two disease courses (Bergink et al. Reference Bergink, Boyce and Munk-Olsen2015a ): an isolated postpartum psychosis with vulnerability to affective psychosis only after birth or postpartum psychosis as an expression of bipolar mood disorder with non-perinatal episodes (Chaudron & Pies, Reference Chaudron and Pies2003; Di Florio et al. Reference Di Florio, Munk-Olsen and Berginkin press). The diagnostic criteria for puerperal bipolar disorder and Donkin psychosis as described by Brockington (Reference Brockington2016) have neither been validated nor field tested, and therefore are not currently suitable for implementation in population-based epidemiological studies.