The COMPARE study: Prevalence and COMplications of Postpartum Asymptomatic urinary REtention.

Objective:

The prevalence, complications and natural course of asymptomatic postpartum urinary retention.



Study design:

An observational prospective cohort study.



Study population:

Women who deliver vaginally in the participating hospitals of 18 years and older and have spontaneous micturition.



Intervention:

The volume of the first void after the delivery is measured in all women who deliver in the participating hospitals. After this, a non invasive abdominal bladderscan to measure the post void residual bladder volume (PVRV) will be done. Patients with an abnormal PVRV (≥ 150 ml) are asked to participate in the study; the natural course of asymptomatic postpartum urinary retention is followed by bladderscans. Patients with a normal PVRV are asked to participate in the control group.



Outcome measures:

Primary Objective: Micturition related quality of life after 3 months in women with asymptomatic postpartum urinary retention in a prospective cohort.

Secondary Objectives:

1. Prevalence of asymptomatic postpartum urinary retention;

2. Prevalence of urinary tract morbidity and care consumption in patients with asymptomatic postpartum urinary retention;

3. Identification of prognostic factors for asymptomatic postpartum urinary retention;

4. Costs related to asympyomatic abnormal post void residual volume.



Power/data analysis:

A difference of 8 points at the total score of the UDI-6 is considered to be clinically relevant. A standard deviation of 16 points is assumed to realize an effect-size of 0.5. To achieve a power of 90% for detecting a significant difference, ¦Á of 0.05, a total of 86 patients with asymptomatic urinary retention is needed when performing a 2-sided unpaired T-Test. Anticipating a drop-out of about 15%, we want to include 100 patients.

Postpartum urinary retention (PUR) is a complication with a varying prevalence, from 0.5 - 18%. For asymptomatic PUR, i.e. the ability to void but with a post residual volume (PVRV) of ≥150 ml, the estimation of prevalence is between 10-45%. Untreated and unrecognized urinary retention can lead to distension of the detrusor muscle of the bladder. This serious complication can cause denervation, urinary tract infections, pyelonefritis, urinary dysfunction, renal failure and even bladder rupture.

In most hospitals, the residual bladder volume postpartum after spontaneous micturition is not measured and recorded. Therefore, little is known about the natural course and potential long term complications. The abcense of standard screening for abnormal post void residual volume means that morbidity due to inadequate bladder emptying are underdiagnosed.

First measurement: After delivery;

Last measurement: Three months postpartum.

Patients will be bladderscanned after spontaneous micturition. All patients with a post void residual volume (PVRV) > 150 ml will be included; they will receive measurements of the PVRV until it has normalized. These patients will fill out questionnaires and come back after three months.

Patients with a PVRV less than 150 ml are asked to participate in the control group and will fill out questionnaires.