Markers for mental unhealth during pregnancy - predictors for delivery outcome Background: Population based studies report increasing mental ill-health levels of women in reproductive ages. Routine ante- and perinatal data is registered by the Nurse Midwife, and forwarded to the Medical Birth Registry of Sweden. No standard variables exist for identifying mental health status. An electronic medical registry (EMR) as a perinatal record system is in use since 1997, at Malmö University Hospital, Sweden. It holds variables possible for follow-up studies and is searchable for free-text. The EMR is used by all clinical staff involved with the pregnant woman. Objectives: To identify markers for mental unhealth in pregnancy in registry data to predict delivery outcome. Description: Patient records from 2001 to 2006 with 22,053 pregnancies were selected. Theoretical markers of mental unhealth related words were identified and tested in a sub-sample. A free-text-search among all 22,053 patient records was performed to identify the occurrence of each of the selected markers. Results: Ten words relating to mental health instruments were chosen for the free-text database search. Occurrence of reported words as "panic", “anxiety” and “stress” showed an increase OR for instrumental delivery and acute Caesarean section. The phrase "anti-depressive" seems to lower the OR for these outcomes. Preliminary data indicate an increased risk of obstetric complications at delivery associated with some of the markers for mental unhealth for nulliparous women. Ethical approval, no. 350/2007.