Background
Objectives
Methods/design
Search strategy
Establishment of the International Weight Management in Pregnancy IPD Collaboration
Study year | Country | Study characteristics | Outcomes | Sample size | |
---|---|---|---|---|---|
Maternal | Fetal | ||||
Althuizen 2012 | Netherlands | Ethnically diverse; no BMI restrictions; age, nr; GA at inclusion, <14 weeks; glucose status, nr; other risk factors, nr | GWG, GDM, preterm delivery, CS | Birth weight, macrosomia | 269 |
Barakat 2009 | Spain | Caucasian; BMI restrictions, nr; age, 25–35 years; GA at inclusion, nr (total at least 26 weeks intervention); glucose status, nr; no known pre-existing health problems | GWG, GA, preterm delivery | Birth weight, LGA, SGA, AS, macrosomia (>4,000 g) | 142 |
Barakat 2011 | Spain | Spanish (White); BMI restrictions, nr; age, 23–38 years; GA at inclusion, first prenatal visit; glucose status, nr; no known pre-existing health problems | GWG, GA CS, vaginal delivery | Birth weight, AS | 80 |
Barakat 2013 | Spain | Caucasian; no BMI restrictions; age, nr; GA at inclusion, <10 weeks; glucose status, nr; no known pre-existing health problems | GWG, GA, GDM, PIH, preterm delivery | Birth weight, AS | 765 |
Bogaerts 2012 | Belgium | Ethnically diverse; BMI, ≥29 kg/m2; age, nr; GA at inclusion, <15 weeks; nondiabetic; other risk factors, nr | GWG, GA, PE, PIH, GDM, IOL, CS, vaginal delivery | Birth weight, AS | 197 |
Cavalcante 2009 | Brazil | Race, nr; no morbid obesity; age restrictions, nr; GA at inclusion, 16–20 weeks; glucose status, nr; no known pre-existing health problems | GWG, preterm delivery | Birth weight | 71 |
Clapp 1997 | USA | Race, nr; no morbid obesity; age restrictions, nr; GA at inclusion, 8 weeks; glucose status, nr; no known pre-existing health problems | GWG | Birth weight | 51 |
Clapp 2000 | USA | Race, nr; no morbid obesity; age restrictions, nr; GA at inclusion, 8 weeks; glucose status, nr; no known pre-existing health problems | GWG, GA | Birth weight | 12 |
Dodd 2014 | Australia | Race, nr; BMI, ≥25 kg/m2; age restrictions, nr; GA at inclusion, <20 weeks; nondiabetic; other risk factors, nr | PE, PIH, GDM, IOL, CS, preterm delivery | LGA, macrosomia (>4,000 g), hypoglycaemia, shoulder dystocia, admission to NICU | 1,582 |
El Beltagy 2013 | Egypt | Race, nr; BMI, obese; age restrictions, nr; GA at inclusion, first antenatal visit; glucose status, nr; other risk factors, nr | GWG, GDM | Birth weight, macrosomia | 100 |
Grant 2013 | Canada | Race, predominantly non-Caucasian; BMI restrictions, nr; age, >18 years, GA at inclusion, nr; glucose status, impaired glucose tolerance or GDM; no known pre-existing health problems | GWG | Birth weight, macrosomia | 47 |
Guelinckx 2010 | Belgium | Caucasian; BMI, ≥29 kg/m2; age restrictions, nr; GA at inclusion, <15 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, PE, PIH, IOL, CS | Birth weight, LGA | 85 |
Haakstad 2011 | Norway | Race, nr; BMI restrictions, nr; age restrictions, nr; GA at inclusion, <24 weeks; glucose status, nr; no known pre-existing health problems | GWG | 105 | |
Hui 2006 | Canada | Ethnically diverse; BMI restrictions, nr; age restrictions, nr; GA at inclusion, <26 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, GDM | Birth weight, LGA | 45 |
Hui 2011 | Canada | Race, nr; BMI restrictions, nr; age restrictions, nr; GA at inclusion, 20–26 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, GDM, CS | Birth weight, LGA | 224 |
Jackson 2010 | USA | Ethnically diverse; BMI restrictions, nr; age, >18 years; GA at inclusion, <26 weeks; glucose status, nr; other risk factors, nr | GWG | 321 | |
Jeffries 2009 | Australia | Race, nr; BMI restrictions, none; age, >18 to <45 years, GA at inclusion, <14 weeks; nondiabetic; other risk factors, nr | GWG, PE, PIH, GDM , preterm delivery, CS | Birth weight, LGA, SGA, hypoglycaemia, shoulder dystocia | 236 |
Khaledan 2010 | Iran | Race, nr; BMI restrictions, nr; age restrictions, nr; GA at inclusion, 24–32 weeks; no diabetes mellitus type 1 (DM1) with poor control; no known pre-existing health problems | GWG, GA, CS | Birth weight | 39 |
Khoury 2005 | Norway | Caucasian; BMI, 19–32 kg/m2; age, 21–38 years; GA at inclusion, 17–20 weeks; nondiabetic; no known pre-existing health problems | GWG, PE, preterm delivery | Birth weight, SGA, intra-uterine death | 290 |
Luoto 2011 | Finland | Race, nr; BMI, >17 kg/m2; age, >18 years; GA at inclusion, 8–12 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, PE, GDM | Birth weight, LGA, SGA | 399 |
Nascimento 2011 | Brazil | Race, nr; BMI, >26 kg/m2; age >18 years; GA at inclusion, 14–24 weeks; nondiabetic; no known pre-existing health problems | GWG, PIH, GDM, CS | Birth weight, AS, LGA, SGA | 82 |
Ong 2009 | Australia | Race, nr; obese; age restrictions, nr; GA at inclusion, 18 weeks; nondiabetic; other risk factors, nr | GWG | 12 | |
Oostdam 2012 | Netherlands | Ethnically diverse; BMI, ≥25.0 kg/m2; age, >18 years; GA at inclusion, <20 weeks; nondiabetic; no known pre-existing health problems | GWG, GDM | Birth weight | 124 |
Phelan 2011 | USA | Ethnically diverse; BMI, ≥19.8–26.0 kg/m2; age >18 years; GA at inclusion, 10–16 weeks; glucose status, nr; no known pre-existing health problems | GWG, GA, PE, PIH, GDM, preterm delivery, CS | Birth weight, macrosomia, birth weight <2,500 g | 401 |
Poston 2013 | UK | Race, nr; BMI, ≥30 kg/m2; age restrictions, nr; GA at inclusion, >15+0 weeks and <17+6; nondiabetic; no known pre-existing health problems | GA, GWG, PE, GDM, mode of delivery | Birth weight, macrosomia, still birth | 183 |
Prevedel 2003 | Brazil | Race, nr; BMI restrictions, nr; age restrictions, nr (primiparous or adolescents); GA at inclusion, 16–20 weeks; glucose status, nr; no known pre-existing health problems | GWG, preterm delivery | Birth weight, SGA | 132 |
Rauh 2013 | Germany | Race, nr; BMI, ≥18.5 kg/m2; age, ≥18 years; GA at inclusion, <18 weeks; nondiabetic; no known pre-existing health problems | GWG, GDM, IOL, CS, preterm delivery | LGA, SGA | 250 |
Sagedal 2014 | Norway | Race, nr; BMI, ≥19 kg/m2; age, ≥18 years; GA at inclusion, <20 weeks; nondiabetic; no known pre-existing health problems | GWG, GDM, CS | LGA | 600 |
Stafne 2012 | Norway | White; no BMI restrictions; age, >18 years; GA at inclusion, 18–22 weeks; nondiabetic; no known pre-existing health problems | GA, PE, PIH, GDM, CS | Birth weight, AS, LGA, admission to NICU | 124 |
Vesco 2013 | USA | Race, nr; BMI, ≥30 kg/m2; age, nr; GA at inclusion, <20 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, PE, PIH, GDM, CS, preterm delivery | Birth weight, LGA, SGA, macrosomia (4,000 g) | 114 |
Vinter 2011 | Denmark | Caucasian; BMI, 30–45 kg/m2; age, 18–40 years; GA at inclusion, 10–14 weeks; nondiabetic; no known pre-existing health problems | GWG, PE, PIH, GDM, CS | LGA, admission to NICU | 855 |
Vitolo 2011 | Brazil | Race, nr; BMI restrictions, none; age, <35 years; GA at inclusion, 10–29 weeks; nondiabetic; no known pre-existing health problems | GWG, PE, PIH, GDM, preterm birth | Birth weight | 315 |
Walsch 2012 | Ireland | Race, nr; BMI restrictions, nr; age, >18 years; GA at inclusion, <18 weeks; nondiabetic; no known pre-existing health problems | GWG, GA, preterm delivery, IOL, CS | Birth weight, macrosomia | 304 |
Wolff 2008 | Denmark | Caucasian; BMI, ≥30 kg/m2; age, >18 to <45 years; GA at inclusion, <18 weeks; nondiabetic; no known pre-existing health problems | GWG PE, PIH, GDM , CS | Birth weight | 800 |
Yeo 2012 | USA | Ethnically diverse; BMI, >19.8 kg/m2; no age restrictions; GA at inclusion, 18 weeks; nondiabetic; no known pre-existing health problems | GWG, PE, PIH | Birth weight | 17 |
Inclusion and exclusion criteria
Outcome measures
Maternal outcomes | Fetal outcomes |
---|---|
Pre-eclampsia | Intrauterine death |
Pregnancy induced hypertension | Small for gestational age |
Gestational diabetes mellitus | Large for gestational age |
Preterm delivery | Admission to NICU |
Caesarean section | Shoulder dystocia |
Thromboembolism | >1 perinatal complication |
Admission to high dependency unit/intensive treatment unit | Birth trauma |
Weight gain in pregnancy | Long-term neurological sequelae |
Long-term metabolic sequelae |
Study quality assessment and data collection
Sample size considerations
Characteristics | Existing systematic reviews | Published and ongoing primary studies | Proposed IPD meta-analysis |
---|---|---|---|
Consistent inclusion and exclusion criteria e.g. BMI, risk status | x | √ | √ |
Assessment of effect of prognostic factors on treatment effect e.g. diabetic status, chronic hypertension | x | √ | √ |
Missing data observed and accounted at individual level | x | √ | √ |
All critically important maternal and fetal outcomes considered | √ | x | √ |
Potential for sufficient power to assess for differential treatment effect across groups e.g. BMI, ethnicity, race, parity | x | x | √ |
Standardisation of statistical analysis across studies | x | N/A | √ |
Correlation between multiple end points accounted e.g. each participant providing data on gestational weight gain in various trimesters and weight retention postpartum | x | √ | √ |
Up to date follow-up information, potentially longer than that used in the original study publication | x | x | √ |
Subgroups | Control group SD | Sample size required to detect a 2.5-kg reduction in gestational weight gain | Control group: probability of adverse maternal and fetal outcomes | Sample size required to detect a 30% reduction in adverse maternal and fetal outcomes | |
---|---|---|---|---|---|
BMI | Obese | 7.5 | 300 | 0.30 | 770 |
Overweight | 7.5 | 300 | 0.20 | 1,290 | |
Normal | 5.1 | 140 | 0.12 | 2,330 | |
Age | <20 years | 7.12 | 270 | ||
≥20 years | 5.87 | 184 | |||
Ethnicity | Caucasian | 3.4 | 64 | ||
Asian | 3.8 | 78 | |||
African | 5.1 | 140 | |||
Parity | <1 | 6.28 | 212 | ||
≥1 | 6.68 | 238 | |||
Risk factors like diabetes | High risk | 6.81 | 248 | ||
Low risk | 6.67 | 236 |
Data analysis
Summarising the overall effect of weight management interventions
Examining heterogeneity and estimating intervention effects within each subgroup
Evaluation of potential prognostic factors for weight change in pregnancy
Network meta-analyses
Exploration of sources of bias: unavailable data and publication bias
Health economic evaluation
Discussion
Trial | Year | Corresponding author | Country | Affiliation |
---|---|---|---|---|
Althuizen | 2012 | Mireille van Poppel | Amsterdam, Netherlands | Department of Public and Occupational Health, EMGO + Institute for Health and Care Research, VU University Medical Center, Amsterdam |
Barakat | 2009, 2011, 2013 | Ruben Barakat Carballo | Madrid, Spain | Facultad de Ciencias de la Actividad Fı’sica y del Deporte-INEF, Universidad Polite’cnica de Madrid |
Bogaerts | 2012 | Annick Bogaerts | Leuven, Belgium | Division of Mother and Child, Department of Obstetrics and Gynaecology, Limburg Catholic University College Hasselt and University Hospitals KU Leuven |
Cavalcante | 2009 | Jose G Cecatti | Sao Paulo, Brazil | Department of Obstetrics and Gynecology, School of Medical Sciences, University of Campinas (UNICAMP) |
Clapp | 1997, 2000 | Beth Lopez | Cleveland, USA | Departments of Reproductive Biology and Obstetrics and Gynecology and the Schwartz Center for Metabolism and Nutrition, Case Western Reserve University and MetroHealth Medical Center |
Dodd | 2014 | Jodie Dodd | Adelaide, Australia | Discipline of Obstetrics and Gynaecology, School of Paediatrics and Reproductive Health, The University of Adelaide |
El Beltagy | 2013 | Nermeen El Beltagy | Alexandria, Egypt | Department of Obstetrics and Gynecology, Alexandria University |
Guelinckx | 2010 | Roland Devlieger | Leuven, Belgium | Division of Mother and Child, Department of Obstetrics and Gynaecology, University Hospitals KU Leuven |
Haakstad | 2011 | Lene Haakstad | Oslo, Norway | Norwegian School of Sport Sciences, Department of Sports Medicine |
Hui | 2006, 2011 | Gary Shen | Manitoba, Canada | Department of Internal Medicine, University of Manitoba, Winnipeg |
Jeffries | 2009 | Alexis Shub | Melbourne, Australia | Department of Obstetrics and Gynaecology, University of Melbourne |
Khaledan | 2010 | Narges Motahari | Babolsar, Iran | Dept. Physiology, School of Physical Education, Mazandaran University |
Khoury | 2005 | Janette Khoury | Oslo, Norway | Department of Obstetrics and Gynecology, National University Hospital |
Luoto | 2011 | Riitta Luoto | Helsinki, Finland | UKK Institute for Health Promotion Research |
Nashimento | 2011 | Jose G Cecatti, PhD MD | Sao Paulo, Brazil | Department of Obstetrics and Gynecology, School of Medical Sciences, University of Campinas (UNICAMP) |
Ong | 2009 | Kym Guelfi | Crawley, Australia | School of Sport Science, Exercise and Health, The University of Western Australia |
Oostdam | 2009 | Mireille van Poppel | Amsterdam, Netherlands | Department of Public and Occupational Health, EMGO + Institute for Health and Care Research, VU University Medical Center, Amsterdam |
Petrella | 2013 | Fabio Facchinetti | Modena, Italy | Mother-Infant Department, University of Modena and Reggio Emilia |
Phelan | 2011 | Suzanne Phelan | San Luis Obispo, USA | Kinesiology Department, California Polytechnic State University |
Poston | 2013 | Lucilla Poston | London, UK | King’s College London, Division of Women’s Health, Women’s Health Academic Centre |
Prevedel | 2003 | Tânia T Scudeller Prevedel | Sao Paulo, Brazil | Department of Obstetrics, Faculty of Medicine, Botucatu |
Rauh | 2013 | Kathrin Rauh | Munich, Germany | Else Kroener-Fresenius-Center for Nutritional Medicine, Chair of Nutritional Medicine, Technische Universität München |
Renault | 2013 | Kristina Renault | Copenhagen, Denmark | Departments of Obstetrics and Gynecology, Hvidovre Hospital, University of Copenhagen |
Sagedal | 2014 | Linda Reme Sagedal | Kristiansand, Norway | Department of Obstetrics and Gynecology, Sorlandet Hospital |
Stafne | 2012 | Signe Nilssen Stafne and Siv Mørkved | Trondheim, Norway | Department of Public Health and General Practice, Faculty of Medicine, Norwegian University of Science and Technology |
Vesco | 2013 | Kimberly Vesco | Portland, USA | Center for Health Research, Portland |
Vinter | 2011 | Christina Vinter | Odense, Denmark | Department of Gynecology and Obstetrics, Odense University Hospital |
Vitolo | 2011 | Vitolo | Porto Alegre, Brazil | Department of Nutrition and the Graduate Program in Health Sciences, Federal University of Health Sciences of Porto Alegre |
Walsh | 2012 | Fionnuala M McAuliffe | Dublin, Ireland | UCD Obstetrics and Gynaecology, School of Medicine and Medical Science, University College Dublin, National Maternity Hospital, Dublin, Ireland |
Wolff | 2008 | Arne Astrup | Copenhagen, Denmark | Department of Human Nutrition, Faculty of Life Science, Copenhagen University |
Yeo | 2000 and 2012 | Seonae Yeo | Chapel Hill, North Carolina, USA | School of Nursing, University of North Carolina at Chapel Hill |