Placenta praevia and accreta: analysis of a two-year experience.

OBJECTIVE: Our purpose was to determine the relationship between previous caesarean section and subsequent development of placenta praevia and placenta praevia with accreta.

METHOD: A retrospective review of the case records of all women delivered with the diagnosis of placenta praevia during the 2-year period from January 1, 1995, to December 31, 1996, at the tertiary referral centre, Princess Badeea Teaching Hospital, in north Jordan.

RESULTS: There were 18, 651 deliveries in the study period. 65 (0.35%) had placenta praevia, 21 (32.3%) of whom had a history of previous caesarean section. The incidence of placenta praevia was significantly increased in those with a previous caesarean section (1.87%) compared with those with an unscarred uterus (0.25%); p < 0.0001). This risk increased as the number of previous caesarean sections increased: 1.78% for one previous section; 2.4% for two, and 2.8% for three or more. The incidence of anterior placenta praevia and placenta accreta was significantly increased in those with previous caesarean scars. In the group without antecedent of caesarean section, accretism risk was 9%, with one section or more 40.8% (p < 0.005).

CONCLUSION: There is a high association between anterior placenta praevia, placenta accreta and previous caesarean section. This was enhanced with the increasing number of previous caesarean sections. Patients with an antepartum diagnosis of placenta praevia who have had a previous caesarean section should be considered at high risk of developing placenta praevia and accreta.