Blood flow to the scarred gravid uterus at 22–24 weeks of gestation
Article first published online: 1 OCT 2013
© 2013 Royal College of Obstetricians and Gynaecologists
BJOG: An International Journal of Obstetrics & Gynaecology
Special Issue: Management of pregnancy after caesarean section
Volume 121, Issue 2, pages 210–215, January 2014
How to Cite
Blood flow to the scarred gravid uterus at 22–24 weeks of gestation. BJOG 2014;121:210–215., , , .
- Issue published online: 26 DEC 2013
- Article first published online: 1 OCT 2013
- Manuscript Accepted: 29 JUL 2013
- Regional Health Authority of North Norway
- Maternal haemodynamics;
- previous caesarean section;
- uterine artery blood flow;
- uterine artery Doppler
To compare uterine artery volume blood flow (Quta), vascular resistance (Ruta), pulsatility index (Uta PI), and the fraction of maternal cardiac output (CO) distributed to the uteroplacental circulation in pregnant women with and without a previous caesarean section.
Cross-sectional observational study.
University hospital in Norway.
Thirty-two pregnant women with previous caesarean section and 32 matched controls.
Ultrasonography was used to measure uterine artery diameter and blood flow velocity between 22+0 and 23+6 weeks of gestation. Impedance cardiography was used to assess maternal haemodynamics.
Main outcome measures
Quta, Ruta, Uta PI, and the fraction of maternal CO distributed to the uteroplacental circulation.
The mean Quta was 356.26 ± 213.72 ml/minute in cases and 456.41 ± 209.70 ml/minute in controls (P = 0.038). Ruta was significantly (P = 0.026) higher among cases compared with controls (0.32 ± 0.20 versus 0.22 ± 0.14 mmHg/ml/minute), but the Uta PI did not differ between the groups (0.93 ± 0.23 versus 0.92 ± 0.47; P = 0.929). The fraction of maternal CO distributed to the uteroplacental circulation was 5.75 ± 3.68% in cases and 8.45 ± 5.02% in controls (P = 0.014).
Uterine artery volume blood flow and the fraction of maternal cardiac output distributed to the uteroplacental circulation are lower, and uterine vascular resistance (but not Uta PI) is higher, in women with previous caesarean section compared with the control group.