Study	Reason for exclusion
Ahokas 1998	Not an RCT: a case report study of two women (oestrogen as treatment).
Ahokas 1999a	Not an RCT: a case report study of two women (oestrogen as treatment).
Ahokas 1999b	Not an RCT: a case report study of two women suffering from puerperal psychosis (oestrogen as treatment).
Ahokas 2000	Not an RCT: a pilot study that included 10 women suffering from postpartum psychosis recruited consecutively. No randomisation process was reported (oestrogen as treatment).
Ahokas 2001	Not an RCT: an open label study that included 23 women (oestrogen as treatment).
Ball 1999	Not an RCT: a case report study (oestrogen as treatment).
Cizza 1997	A letter to the editor commenting on the Gregoire trial. No original data.
Dalton 1985	Not an RCT: an open study that included 100 women who self‐selected to receive treatment and were compared with untreated women (progesterone as prophylaxis).
Dalton 1989	Not an RCT: an open study that included 215 women with a previous history of postpartum depression who were encouraged to receive both injections and suppositories of progesterone for 8 weeks. Details of the intervention were unclear and the different dosage of progesterone were used by women. There was no uniform scoring system used to examine a recurrence of postpartum depression (progesterone as prophylaxis).
Kumar 2003	Not an RCT: an open study that included 29 pregnant women with a history of bipolar and schizoaffective disorder. Variable oestrogen doses were used (oestrogen as prophylaxis).
Sichel 1995	Not an RCT: an open label study that included 11 women with a history of either non‐psychotic major depressive episode or manic postpartum psychosis (oestrogen as prophylaxis).
Van Der Meer 1984	The methodology of this study was inadequate. The sample size was only 10 women and no randomisation or blinding details were provided (progesterone as prophylaxis).

RCT: randomised controlled trial