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Care of Women with Obesity in Pregnancy (Green-top Guideline No. 72)

Published: 22 November 2018


Obesity is becoming increasingly prevalent in the UK population and has become one of the most commonly occurring risk factors in obstetric practice with 21.3% of the antenatal population being obese and fewer than one-half of pregnant women (47.3%) having a body mass index (BMI) within the normal range. Pregnant women who are obese are at greater risk of a variety of pregnancy-related complications compared with women of normal BMI, including pre-eclampsia and gestational diabetes. Pregnant women who are obese are also at increased risk of caesarean birth. Maternal size can make the assessment of fetal size, presentation and external monitoring of fetal heart tracing more challenging during pregnancy. Initiation and maintenance of breastfeeding are also more difficult in the women with obesity.

While the majority of the recommendations within this guideline pertain to women with a BMI 30 kg/m2 or greater, some recommendations are specific to women in the higher classes of obesity only. Obese women with a BMI below a specified threshold may also benefit from recommendations in a higher BMI group, depending on individual circumstances. However, the chosen BMI cut-offs reflect careful consideration given to the balance of medical intervention versus risk, differences in local prevalence of maternal obesity and resource implications for local healthcare organisations.

The recommendations cover interventions prior to conception, and during and after pregnancy.

COVID disclaimer

This guideline developed as part of the regular programme of Green-top Guidelines, as outlined in our document Developing a Green-top Guideline: Guidance for developers, and prior to the emergence of COVID-19.

Version history

This is the first edition of this guideline; the second edition is currently in development.

Please note that the RCOG Guidelines Committee regularly assesses the need to update the information provided in this publication. Further information on this review is available on request.

Developer declaration of interests

Professor FC Denison: Professor Denison has several grant applications pending and has design protection rights for a device. Professor Denison is also Vice Chair of NICE MTAC Board and a Member of Grant Awarding Bodies (Tenovus, CSO).

Dr NR Aedla: None declared.

Dr O Keag: None declared.

Dr K Hor: None declared.

Professor RM Reynolds: None declared.

Dr A Milne: Dr Milne had received an Edinburgh and Lothian’s Health Foundation £33,458 grant for project entitled, ‘Integrated ultrasound needle to facilitate placement of regional anaesthesia in obese pregnant women.”

Mrs A Diamond: Mrs Diamond has received honoraria for diet input to SPCDs study day. Mrs Diamond has also received payment for diet/lifestyle lecture on diabetes course (Oct 2016).

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