The association between maternal intra-abdominal pressure and hypertension in pregnancy

Pregnancy leads to a state of chronically increased intra-abdominal pressure (IAP) caused by a growing fetus, fluid, and tissue. Increased intra-abdominal pressure is leading to state of Intra-Abdominal Hypertension (IAH) and Abdominal Compartment Syndrome. Clinical features and risk factors of preeclampsia is comparable to abdominal compartment syndrome. IAP may be associated with the hypertension in pregnancy (HIP).

The study aimed to determine the antepartum and postpartum IAP levels in women undergoing caesarean delivery (CD) and association between hypertension in pregnancy, and antepartum and postpartum IAP levels in women undergoing CD.

Seventy pregnant women (55 normotensive, 15 HIP) undergoing antepartum, non-emergency CD, had their intravesical pressure measured before and after the CD, the intravesical pressure measurements obtained with the patient in the supine position were considered to correspond to the IAP. Multivariable linear regression models were used to study associations between intraabdominal pressure and baseline characteristics in normotensive pregnancies and hypertensive pregnancies.

In normotensive pregnancies at mean gestation age of 38.2 weeks (95%CI 37.9 to 38.6), mean antepartum IAP was 12.7 mmHg(95%CI 11.6 to 13.8) and the mean postpartum IAP was 7.3 mmHg (95% CI 11.6 to 13.8). Multivariable linear regression models showed HIP group antepartum IAP positively associated with coefficient value of 1.617 (p = 0.268) comparing with normotensive pregnancy group. Postpartum IAP in HIP group positively associated with coefficient value of 2.519 (p = 0.018) comparing with normotensive pregnancy group. IAP difference is negatively associated with HIP (coefficient -1.013, p = 0.179).

In normotensive pregnancies at term, the IAP was in the IAH range of the non-pregnant population. Higher Antepartum IAP and Postpartum IAP are associated with HIP. Reduction of IAP from antepartum period to postpartum period was less with HIP.