F53 vs F54

Both can present as a mood or behavioural change beginning shortly after childbirth.

• F53 applies when the mental or behavioural disturbance is itself the primary disorder, with no separate diagnosed physical disease it is affecting.
• F54 applies when an actual physical disease has been diagnosed (such as postpartum thyroiditis) and psychological or behavioural factors are documented as affecting that disease's course or management.
• Checking whether a specific physical disease has actually been diagnosed, separate from the mood or behavioural change itself, is the decisive step.
• The presence of physical signs pointing to a diagnosable medical condition (e.g. thyroid findings) should prompt consideration of F54 over a primary F53 diagnosis.

What weakens F53: Evidence of an actual diagnosed physical disease with a documented link to the psychological/behavioural change weakens F53 and favours F54; the absence of any diagnosed physical disease favours F53.

Both can begin within the puerperium window; the decisive factor is whether a separate physical disease has been diagnosed, not the timing itself.

A vignette should specify whether any physical disease has actually been diagnosed and linked to the presentation, not just that the presentation began postpartum.

Whether a specific physical disease has been diagnosed, and whether psychological/behavioural factors are documented as affecting its course.

Diagnosing a primary puerperium-associated disorder without checking whether an underlying diagnosed physical disease better explains the presentation.