Cohort studycited by the Tayebat archiveabstract only checked A-BAR-22 standard review
Pregnancy after weight-loss surgery
Outcomes of pregnancy after bariatric surgery.
Overview
Johansson K et al.. N Engl J Med 2015 · PMID 25714159 · DOI 10.1056/NEJMoa1405789
Less gestational diabetes and fewer large babies, but more small babies.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Pregnancy
- How was the study done?
Matched cohort
- How many people, animals or samples were studied?
670 exposed
- What was actually found?
Mixed
- How large was the observed effect?
SGA OR 2.20; GDM OR 0.25
- What do the results mean in everyday life?
Pregnancy after surgery needs monitoring
- What are the study's limitations?
Few deaths
- What does it say about Elawady's specific claim?
Mixed
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Causality
Scientific in-depth review
1. Full reference
- Authors
- Johansson K, Cnattingius S, Näslund I, Roos N, Trolle Lagerros Y, Granath F, Stephansson O, Neovius M
- Journal
- N Engl J Med
- Year
- 2015
- Identifier
- PMID 25714159 DOI 10.1056/NEJMoa1405789
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
COI: not stated in record | Grants: none listed
2. Research question
Pregnancy outcomes after bariatric surgery
3. Study design and population
- Study design
- Cohort study – Matched population-based cohort (Swedish Medical Birth Register)
- Population
Singleton pregnancies
- Country
Sweden
- Period
2006-2011
- Sample size
670 post-surgery pregnancies, up to 5 matched controls each
4. Methods and endpoints
- Exposure / intervention
Prior bariatric surgery
- Comparator
Pregnancies matched on presurgery BMI etc.
- Endpoints
GDM, LGA, SGA, preterm, stillbirth/neonatal death
5. Actual results
- Results
GDM 1.9% vs 6.8% (OR 0.25); LGA 8.6% vs 22.4% (OR 0.33); SGA 15.6% vs 7.6% (OR 2.20); gestation -4.5 days; preterm 10.0% vs 7.5% (NS); stillbirth/neonatal death 1.7% vs 0.7% (OR 2.39, 0.98-5.85).
- Absolute risks
not reported
- Authors' conclusion
Reduced GDM and excessive fetal growth; shorter gestation, increased SGA, possibly increased mortality.
6. Strengths
- Population-based, matched
7. Weaknesses
- Small number of deaths
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
9. Assessment of the statistical interpretation
10. Relevance to the specific claim
Shows both benefits and harms in pregnancy.
11. Independent contrary findings
12. Transferability to Germany and Europe
European.
13. Overall methodological judgement
Mixed evidence.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | low |
| Directness | indirect |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- Sleeve gastrectomy (and bariatric surgery in general) is a lethal operation that kills patients / shortens life. – Studies with mixed or unclear results
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
Listed in the archive bibliography only; the archive gives no specific interpretation.
- A. What was actually studied?
Pregnancy outcomes
- B. What did the authors find?
Mixed benefits and harms
- C. What conclusions do the authors themselves draw?
As found
- D. What does the archive derive from it?
Not used in narrative.
- E. Is this derivation scientifically justified?
Not applicable; mixed results.
- Adequacy of the interpretation (by the archive)
- not applicable