BACKGROUND: Traumatic brain injury is a leading cause of death and disability. 
Progesterone is a potential neuroprotective drug to treat patients with 
traumatic brain injury.
OBJECTIVES: To assess the effectiveness and safety of progesterone in people 
with acute traumatic brain injury (TBI).
SEARCH STRATEGY: We searched: the Cochrane Injuries Group's Specialised Register 
(to April 2010), Cochrane Central Register of Controlled Trials 2010, Issue 1 
(The Cochrane Library), MEDLINE (Ovid) (1950 to April week 1 2010), EMBASE 
(Ovid) (1980 to week 14 2010), LILACS (to 17 April 2010 ), Zetoc (to 21 April 
2010), Clinicaltrials.gov (17 April 2010 ), Controlled-trials.com (17 April 
2010).
SELECTION CRITERIA: We included published and unpublished randomised controlled 
trials (RCTs) of progesterone versus no progesterone (or placebo) for the 
treatment of acute TBI.
DATA COLLECTION AND ANALYSIS: Two authors independently screened search results 
to identify the full texts of potentially relevant studies for inclusion. From 
the results of the screened searches two authors independently selected trials 
meeting the inclusion criteria, with no disagreement.
MAIN RESULTS: Three studies were included with 315 patients. All three studies 
reported the effects of progesterone on mortality. The pooled relative risk (RR) 
for mortality at end of follow-up is 0.61, 95% confidence interval (CI) 0.40 to 
0.93. Three studies measured disability and found the RR of death or severe 
disability in patients treated with progesterone was 0.77, 95% confidence 
interval (CI) 0.62 to 0.96. Two studies presented data on intracranial pressure 
and adverse events. One study presented blood pressure and temperature data. 
There was no substantial evidence for the presence of heterogeneity.
AUTHORS' CONCLUSIONS: Current clinical evidence from three small RCTs indicates 
progesterone may improve the neurologic outcome of patients suffering TBI. This 
evidence is still insufficient and further multicentre randomised controlled 
trials are required.