[Defect at uterine incision from prior Caesarean section]. / Defekt i uterotomi efter tidligere sectio.

A case of asymptomatic uterine fenestration in 26+3 gestational weeks in a patient who had previously undergone Caesarean section is presented. Controls were planned. In gestational week 34+1 the woman was hospitalized due to lower abdominal pain, but with otherwise normal objective parameters. Ten days later the patient had increasing pain, and a caesarean section was performed. Fenestration was confirmed. This leads to reflections on how to treat and observe such cases, and further discussion about whether early identification of risk patients by ultrasound is possible.