Narrative reviewindependent cross-checkfull text checked I-INTB-23 in-depth review
Abdominal pressure in pregnancy
Intra-abdominal pressure, intra-abdominal hypertension, and pregnancy: a review.
Overview
Chun R, Kirkpatrick AW. Ann Intensive Care 2012 · PMID 22873421 · DOI 10.1186/2110-5820-2-S1-S5
Abdominal pressure is probably raised near term, but most women adapt to it; any role in pre-eclampsia is only a hypothesis. Cortisol is not discussed.
Does the study support the specific claim? Partly · Methodological quality: low
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Review IAP in pregnancy
- How was the study done?
Narrative review
- How many people, animals or samples were studied?
not applicable
- What was actually found?
Few IAP data in pregnancy (e.g. median 22 mmHg at term, 16 mmHg after delivery); pregnancy considered a compensated state; pre-eclampsia link hypothetical
- How large was the observed effect?
not applicable
- What do the results mean in everyday life?
The growing womb may raise abdominal pressure, but whether this causes complications is not known.
- What are the study's limitations?
Narrative review with a single case; no systematic search; measurement methods unvalidated in pregnancy
- What does it say about Elawady's specific claim?
Partly plausible; does not support his general explanation.
- Do the results apply to Germany and Europe?
Universal
- What can explicitly not be concluded from this study?
Cannot conclude that abdominal pressure (or cortisol deficiency, not studied) explains pregnancy health problems
Scientific in-depth review
1. Full reference
- Authors
- Chun R, Kirkpatrick AW
- Journal
- Ann Intensive Care
- Year
- 2012
- Identifier
- PMID 22873421 DOI 10.1186/2110-5820-2-S1-S5
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- full text
- Conflicts of interest and funding
One author (A.W. Kirkpatrick) is PI of a KCI Corporation-funded trial of vacuum therapy in open-abdomen management (no personal benefit) and chairs the WSACS Guidelines Committee; the other declares no competing interests. No specific funding statement.
2. Research question
What is known about intra-abdominal pressure (IAP) and intra-abdominal hypertension in pregnancy?
3. Study design and population
- Study design
- Narrative review – Narrative review with an illustrative case report (Annals of Intensive Care supplement on intra-abdominal hypertension, 2012)
- Population
Pregnant and peripartum women, particularly critically ill parturients; case of a 16-year-old at about 32 weeks with influenza A ARDS
- Country
Canada (authors, Calgary); literature international
- Period
Literature to 2012 (search method not described)
- Sample size
not applicable
- Inclusion and exclusion criteria
not stated
4. Methods and endpoints
- Exposure / intervention
Pregnancy / gravid uterus
- Comparator
not applicable
- Endpoints
IAP, IAH, possible links with pre-eclampsia
- Statistical methods
none
5. Actual results
- Results
Pregnancy physiology: functional residual capacity reduced by at least 20%, plasma volume +50%, cardiac output +30-50%. Few IAP data in pregnancy: one study of 100 healthy term parturients under spinal anaesthesia before elective caesarean found median IAP 22 +/- 2.9 mmHg (range 15-29), falling to 16 mmHg (11-24) after delivery; the authors' own study of 20 term parturients found higher bladder pressures fully supine than at 10 degree left tilt, suggesting the uterus may falsely elevate bladder-measured IAP. Consensus guidelines regard pregnancy as a chronically compensated state of IAH; authors state term pregnancy is likely associated with elevated IAP to which women have adapted. Links of IAH with pre-eclampsia/HELLP and with fetal effects are hypotheses supported only by case reports, historical observations and animal data. Case: ARDS complicated by probable unrecognised abdominal compartment syndrome relieved at laparotomy/caesarean section. Cortisol is not discussed.
- Absolute risks
not applicable
- Authors' conclusion
IAP and IAH in pregnancy have received almost no attention; normal IAP ranges across pregnancy are unknown, current measurement guidelines do not account for the gravid uterus, IAP should be measured in critically ill parturients and in OHSS, and the possible role of IAH in pre-eclampsia and fetal development requires research.
6. Strengths
- Written by experts of the field (WSACS); clear physiological framework
- Identifies measurement problems (position, bladder surrogate) and research gaps
7. Weaknesses
- Narrative review without systematic search or appraisal
- Evidence for IAH-pre-eclampsia link limited to hypotheses, two case reports and historical/animal data
- Single case report used for illustration (no causal inference possible)
- IAP measurement in pregnancy not validated
- Does not address cortisol or general pregnancy complaints
8. Risk of bias
- Orienting tool
- No standard tool fits (narrative review with case report); structured validity judgement
- Type of assessment
- structured assessment based on the full text by a single reviewer (no formal double review)
- Full formal assessment
- no
- Overall risk of bias
- high
- Rationale
Changed from not_assessable to high (structured judgement): as evidence for causal claims this narrative review carries high risk of bias; it is suitable only as hypothesis context. Simplified single-reviewer judgement; no formal tool applies.
| Domain | Judgement | Rationale |
|---|---|---|
| Evidence identification | high | No described search strategy or inclusion criteria. |
| Evidence appraisal | high | No critical appraisal of cited studies; reliance on case reports and hypotheses. |
| Interpretation | some concerns | Authors clearly label the pre-eclampsia link as hypothesis and call for research; advocacy for IAP measurement by WSACS-affiliated author. |
| Conflicts of interest | some concerns | Industry-funded trial (KCI) and WSACS leadership role of one author, disclosed. |
Full-text review (25 October 2026): Added design detail (narrative review plus case report), cited IAP values (22 +/- 2.9 mmHg at term; 16 mmHg post-delivery), statement that pregnancy is a chronically compensated IAH state, absence of any cortisol discussion, author COI (KCI-funded trial, WSACS role). Bias changed from not_assessable to high (structured judgement for causal use).
9. Assessment of the statistical interpretation
Only descriptive IAP values from small cited studies (e.g. median 22 mmHg at term before caesarean, 16 mmHg after delivery); no tests of association with maternal outcomes.
10. Relevance to the specific claim
Gives a kernel of plausibility to 'raised abdominal pressure in pregnancy', but only as a hypothesis for some complications.
11. Independent contrary findings
Established causes of pregnancy complications are multifactorial.
12. Transferability to Germany and Europe
Universal physiology.
13. Overall methodological judgement
Hypothesis-level source: raised IAP at term is likely a common, physiologically compensated state; a contribution of intra-abdominal hypertension to pre-eclampsia or fetal effects is unproven. It gives no support to cortisol deficiency as a cause of pregnancy problems.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | low |
| Risk of bias | high |
| Precision of results | not applicable |
| Directness | indirect |
| Reproducibility | unknown |
| Consistency with the overall evidence | unknown |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Normal IAP values in pregnancy; causal role in pre-eclampsia.
15. Linked fact checks
- Pregnant women develop health problems because pregnancy causes cortisol deficiency and raised intra-abdominal pressure. – Studies with mixed or unclear results