What is sibship and bipolar disorder?

Sibship is a medical term meaning a group of individuals born of the same parents. Factors associated with sibship include birth order, number of siblings or number of births in the family, and inter-birth interval periods. It is not known how these factors may be associated with risk for bipolar disorder. Also see the risk factor topic on familial factors.

What is the evidence for sibship as a risk factor for bipolar disorder?

Moderate to low quality evidence suggests no association between twin birth and bipolar disorder in adulthood.

October 2021

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Last updated at: 12:57 am, 29th October 2021
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Fact Sheet Technical Commentary

NeuRA Libraries

Title Colour Legend:
Green - Topic summary is available.
Orange - Topic summary is being compiled.
Red - Topic summary has no current systematic review available.