A study of over 18,000 deliveries from Jordan found that previous caesarean section increased the risk of placenta praevia (the placenta growing low down in the womb where it partially or completely the baby’s exit) from 0.25% to 1.87%. The greater the number of previous caesareans, the more the risk increased. – 1.78% for one section, 2.4% for two and 2.8% for three or more.
The incidence of placenta accreta (where the placenta has invaded the muscle of the uterus and there is no clear separation) was also increased by a caesarean scar. This greatly increases the risk of haemorrhage when an attempt is made to remove the placenta.
If a women with placenta praeavia had no previous sections, the risk of placenta accreta was 9%, but if she had a previous caesarean scar it was 46%.
This finding confirms a number of others with similar results.
See also Caesareans Increase Future Risks from the Autumn 1998 AIMS Journal).
- Ziadeh S et al. Placental praevia and accreta: an analysis of two years’ experience, J Ob Gyn, 1998; 19: 584-6