American College of Obstetricians and Gynecologists (ACOG). Obesity in pregnancy: ACOG practice bulletin, number 230. Obstet Gynecol. 2021;137(6):e128-e144.

Maxwell C, et al. Guideline No. 391-pregnancy and maternal obesity part 1: pre-conception and prenatal care. J Obstet Gynaecol Can. 2019;41(11):1623–1640.

Maxwell C, et al. Guideline No. 392-pregnancy and maternal obesity part 2: team planning for delivery and postpartum care. J Obstet Gynaecol Can. 2019; 41(11): 1660–1675.

McAuliffe FM, et al. Management of prepregnancy, pregnancy, and postpartum obesity from the FIGO pregnancy and non-communicable diseases committee: a FIGO (International Federation of Gynecology and Obstetrics) guideline. Int J Gynaecol Obstet. 2021;151 Suppl 1(Suppl 1):16–36.

Denison FC, et al. Care of women with obesity in pregnancy: green-top guideline no. 72. BJOG. 2019;126(3):e62-e106.

Royal Australian and New Zealand College of Obstetricians and Gynecologists (RANZCOG). Best practice statement: management of obesity in pregnancy. C-Obs. 2022;49:1–24. Available from: https://ranzcog.edu.au/wp-content/uploads/2022/05/Management-of-Obesity-in-Pregnancy.pdf.

Lorenzo AD. New obesity classification criteria as a tool for bariatric surgery indication. World J Gastroenterol. 2016;22(2):681. Available from: https://doi.org/10.3748/wjg.v22.i2.681.

Kawai T, Autieri MV, Scalia R. Adipose tissue inflammation and metabolic dysfunction in obesity. Am J Physiol Cell Physiol. 2021;320(3):C375–91. https://doi.org/10.1152/ajpcell.00379.2020.

Article  CAS  PubMed  Google Scholar 

Lainez NM, Coss D. Obesity, neuroinflammation, and reproductive function. Endocrinology. 2019;160(11):2719–36.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Carlson NS, Corwin EJ, Lowe NK. Oxytocin augmentation in spontaneously laboring, nulliparous women: multilevel assessment of maternal BMI and oxytocin dose. Biol Res Nurs. 2017;19:382–92. https://doi.org/10.1177/1099800417701831.

Article  CAS  PubMed  PubMed Central  Google Scholar 

• Carlson NS, Hernandez TL, Hurt KJ. Parturition dysfunction in obesity: time to target the pathobiology. Reprod Biol Endocrinol. 2015;3:135. https://doi.org/10.1186/s12958-015-0129-6. Adipokines make exogenous oxytocin less effective for labor initiation and stimulation in those with obesity by blunting uterine contractility yielding prolonged pregnancy and longer labors. Systemic free fatty acids released by excess adipose tissue dysregulate mitochondria, endoplasmic reticulum, and lysosomes, potentially inhibiting effective myometrial contractility.

Ahmed B, Sultana R, Greene MW. Adipose tissue and insulin resistance in obese. Biomed Pharmacother. 2021;137:111315. https://doi.org/10.1016/j.biopha.2021.111315.

Bidne KL, Rister AL, McCain AR, Hitt BD, Dodds ED, Wood JR. Maternal obesity alters placental lysophosphatidylcholines, lipid storage, and the expression of genes associated with lipid metabolism‡. Biol Reprod. 2021;4;104(1):197–210. https://doi.org/10.1093/biolre/ioaa191. PMID: 33048132; PMCID: PMC7946805.

Carlson NS, Frediani JK, Corwin EJ, Dunlop A, Jones D. Metabolomic pathways predicting labor dystocia by maternal body mass index. Am J Perinatology Reports. 2020;10:e68–77. https://doi.org/10.1055/s-0040-1702928.

Article  Google Scholar 

Smith GI, et al. Metabolically healthy obesity: facts and fantasies. J Clin Invest. 2019;129(10):3978–89.

Article  PubMed  PubMed Central  Google Scholar 

•• Zembic A, Eckel N, Stefan N, Baudry J, Schulze MB. An empirically derived definition of metabolically healthy obesity based on risk of cardiovascular and total mortality. JAMA Netw Open. 2021;4(5):e218505. https://doi.org/10.1001/jamanetworkopen.2021.8505. Metabolically healthy obesity (MHO) in adults can be defined as a body mass index > 30 and a systolic BP less than 130mm Hg, no BP-lowering medication, waist-to-hip ratio less than 0.95 for women and less than 1.03 for men, and no diabetes.

Padwal RS, et al. Using the Edmonton obesity staging system to predict mortality in a population-representative cohort of people with overweight and obesity. CMAJ. 2011;183(14):E1059-1066.

Article  PubMed  PubMed Central  Google Scholar 

Sharma AM, Kushner AF. A proposed clinical staging system for obesity. Int J Obes (Lond). 2009;33(3):289–95.

Article  CAS  PubMed  Google Scholar 

Demsky AN, et al. he Edmonton obesity staging system predicts mode of delivery after labour induction. J Obstet Gynaecol Can. 2020;42(3):284–92.

Article  PubMed  Google Scholar 

D’Souza R, Horyn I, Pavalagantharajah S, Zaffar N, Jacob CE. Maternal body mass index and pregnancy outcomes: a systematic review and metaanalysis. Am J Obstet Gynecol MFM. 2019;1(4):100041. https://doi.org/10.1016/j.ajogmf.2019.100041.

Aubry EM, et al. Adverse perinatal outcomes for obese women are influenced by the presence of comorbid diabetes and hypertensive disorders. Sci Rep. 2019;9(1):9793.

Article  PubMed  PubMed Central  Google Scholar 

Vieira MC, et al. Prediction of uncomplicated pregnancies in obese women: a prospective multicentre study. BMC Med. 2017;15(1):194.

Article  PubMed  PubMed Central  Google Scholar 

Simon A, Pratt M, Hutton B, Skidmore B, Fakhraei R, Rybak N, Corsi DJ, Walker M, Velez MP, Smith GN, Gaudet LM. Guidelines for the management of pregnant women with obesity: a systematic review. Obes Rev. 2020;21(3):e12972. https://doi.org/10.1111/obr.12972.

Goldstein RF, Abell SK, Ranasinha S, Misso M, Boyle JA, Black MH, et al. Association of gestational weight gain with maternal and infant outcomes. JAMA. 2017;317(21):2207. Available from: https://doi.org/10.1001/jama.2017.3635.

Shepherd E, Gomersall JC, Tieu J, Han S, Crowther CA, Middleton P. Combined diet and exercise interventions for preventing gestational diabetes mellitus. Coch Data Syst Rev. 2017;(11).

Dipietro L, et al. Benefits of physical activity during pregnancy and postpartum: an umbrella review. Med Sci Sports Exerc. 2019;51(6):1292–302.

Article  PubMed  PubMed Central  Google Scholar 

Hinman SK, et al. Exercise in pregnancy: a clinical review. Sports Health. 2015;7(6):527–31.

Article  PubMed  PubMed Central  Google Scholar 

Owe K, Nystad W, Stigum H, Vangen S, Bø K. Exercise during pregnancy and risk of cesarean delivery in nulliparous women: a large population-based cohort study. Am J Obstet Gynecol. 2016;215(6):791. e1–791.e13. https://doi.org/10.1016/j.ajog.2016.08.014.

Poyatos-León R, et al. Effects of exercise during pregnancy on mode of delivery: a meta-analysis. Acta Obstet Gynecol Scand. 2015;94(10):1039–47.

Article  PubMed  Google Scholar 

Russo LM, Harvey MW, Pekow P, Chasan-Taber L. Physical activity and risk of cesarean delivery in Hispanic women. J Phys Activ Health. 2019;16(2):116–24.

Schoenaker DAJM, de Jersey S, Willcox J, Francois ME, Wilkinson S. Prevention of gestational diabetes: the role of dietary intake, physical activity, and weight before, during, and between pregnancies. Semin Reprod Med. 2020;38(6):352–65. https://doi.org/10.1055/s-0041-1723779.

Article  PubMed  Google Scholar 

Kerrigan A, et al. Obesity and normal birth: a qualitative study of clinician’s management of obese pregnant women during labour. BMC Pregnancy Childbirth. 2015;15:256.

Article  PubMed  PubMed Central  Google Scholar 

Daemers DO, et al. The impact of obesity on outcomes of midwife-led pregnancy and childbirth in a primary care population: a prospective cohort study. BJOG. 2014;121(11):1403–13.

Article  CAS  PubMed  Google Scholar 

Hollowell J, et al. The impact of maternal obesity on intrapartum outcomes in otherwise low risk women: secondary analysis of the Birthplace national prospective cohort study. BJOG. 2014;121(3):343–55.

Article  CAS  PubMed  Google Scholar 

Carlson NS, et al. Labor intervention and outcomes in women who are nulliparous and obese: comparison of nurse-midwife to obstetrician intrapartum care. J Midwifery Womens Health. 2017;62(1):29–39.

Article  PubMed  PubMed Central  Google Scholar 

Rowe R, et al. Outcomes for women with BMI>35kg/m2 admitted for labour care to alongside midwifery units in the UK: a national prospective cohort study using the UK Midwifery Study System (UKMidSS). PLoS ONE. 2018;13(12): e0208041.

Article  PubMed  PubMed Central  Google Scholar 

Jevitt CM, et al. Birth outcomes of women with obesity enrolled for care at freestanding birth centers in the United States. J Midwifery Womens Health. 2021;66(1):14–23.

Article  PubMed  Google Scholar 

•• Relph S, Guo Y, Harvey ALJ, Vieira MC, Corsi DJ, Gaudet LM, et al. Characteristics associated with uncomplicated pregnancies in women with obesity: a population-based cohort study. BMC Pregnancy and Childbirth. BMC Pregnancy and Childbirth. 2021;21(1). Individuals with obesity and no other complications had uncomplicated pregnancies 58.2% of the time. Those with obesity were more likely to have uncomplicated pregnancies if they were younger and multiparous. These authors concluded that those with obesity and no other co-morbid disease could plan birth in low-risk settings.

Zhang J, Landy HJ, Ware Branch D, Burkman R, Haberman S, Gregory KD, et al. Contemporary patterns of spontaneous labor with normal neonatal outcomes. Obstet Gynecol. 2010;116(6):1281–7.

Caughey AB. Is Zhang the new Friedman: how should we evaluate the first stage of labor? Semin Perinatol. 2020;44(2):151215. https://doi.org/10.1016/j.semperi.2019.151215. Epub 2019 Nov 23. PMID: 32067749.

Centers for Disease Control and Prevention. Prevalence of overweight and obesity among adults: United States, 1999-2002 Available from: https://www.cdc.gov/nchs/data/hestat/obese/obese99.htm.

Carhall S, Kallen K, Blomberg M. Maternal body mass index and duration of labor. Eu J Obstet Gynecol and Repro Bio. 2013;171:49–53.

Article  Google Scholar 

Kominiarek MA, Zhang J, Vanveldhuisen P, et al. Contemporary labor patterns: the impact of maternal body mass index. Am J Obstet Gynecol. 2011;205(244):e1-8.

Google Scholar 

Thuillier C, Roy S, Peyronnet V, Quibel T, Nlandu A, Rozenberg P. Impact of recommended changes in labor management for prevention of the primary cesarean delivery. Am J Obstet Gynecol. 2018;218(3):341.e1-341.e9. https://doi.org/10.1016/j.ajog.2017.12.228.

Article  PubMed  Google Scholar 

Cox KJ, King TL. Preventing primary cesarean births: midwifery care. Clin Obstet Gynecol. 2015;58(2):282–93.

Article  PubMed  Google Scholar 

Albers LL, et al. The relationship of ambulation in labor to operative delivery. J Nurse Midwifery. 1997;42(1):4–8.

Article  CAS  PubMed  Google Scholar 

Norman SM, Tuuli MG, Odibo AO, Caughey AB, Roehl KA, Cahill AG. The effects of obesity on the first stage of labor. Obstet Gynecol. 2012;120(1):130–5.

Article  PubMed  PubMed Central  Google Scholar 

Carlson N, Hernandez TL, Hurt KJ. Parturition dysfunction in obesity: time to target the pathobiology. Reprod Biol Endocrinol. 2015;13. https://doi.org/10.1186/s12958-015-0129-6.

D’Souza R, Horyn I, Jacob CE, Zaffar N, Horn D, Maxwell C. Birth outcomes in women with body mass index of 40 kg/m2 or greater stratified by planned and actual mode of birth: a systematic review and meta-analysis. Acta Obstet Gynecol Scand. 2021;100(2):200–9. https://doi.org/10.1111/aogs.14011.

Article  PubMed  Google Scholar 

Hibbard JU, Gilbert S, Landon MB, Hauth JC, Leveno KJ, Spong CY, et al. Trial of labor or repeat cesarean delivery in women with morbid obesity and previous cesarean delivery. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Obstet Gynecol. 2006;108:125–33.