 The Oliviers returned to Britain , and in 1943 , Leigh toured through North Africa as part of a revue for the armed forces stationed in the region . Leigh performed for troops before falling ill with a persistent cough and fevers . In 1944 she was diagnosed as having tuberculosis in her left lung and spent several weeks in hospital before appearing to have recovered . Leigh was filming Caesar and Cleopatra ( 1945 ) when she discovered she was pregnant , then had a miscarriage . Leigh temporarily fell into a deep depression that hit its low point , with her falling to the floor , sobbing in an hysterical fit . This was the first of many major bipolar disorder breakdowns . Olivier later came to recognise the symptoms of an impending episode – several days of hyperactivity followed by a period of depression and an explosive breakdown , after which Leigh would have no memory of the event , but would be acutely embarrassed and remorseful . 
