Best Practice & Research Clinical Obstetrics and Gynaecology 29 (2015) 427e437

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Reducing morbidity and mortality among pregnant obese Ann Harper, MD, FRCOG, FRCPI * Royal Jubilee Maternity Hospital, Belfast, Northern Ireland, UK

Keywords: obesity maternal mortality maternal morbidity pregnancy

Obesity is increasing; in the UK, almost 20% of pregnant women have a body mass index (BMI) of
30 kg/m2. Obese mothers have increased risks of pregnancy complications including miscarriage, congenital anomaly, gestational diabetes, pre-eclampsia, macrosomia, induction of labour, caesarean section, anaesthetic and surgical complications, post-partum haemorrhage, infection and venous thromboembolism. Complications tend to be greater in those with the highest BMIs. In recent triennia, obesity (27e29%) was over-represented in maternal mortality figures. Strategies to reduce morbidity and mortality include calculating BMI at booking visit to identify obese mothers and plan their antenatal care and delivery. This should include nutritional and lifestyle advice, screening for gestational diabetes and pre-eclampsia, thromboembolism risk assessment, antenatal anaesthetic review if BMI is
40 kg/m2, ensuring availability of robust theatre tables and other equipment and involving senior doctors, especially in the labour ward. Afterwards, continuing weight reduction should be encouraged to reduce future pregnancy and health risks. © 2014 Elsevier Ltd. All rights reserved.

Worldwide, obesity has almost doubled since 1980 [1]. In the United States, more than one-third of women are obese, more than one-half of pregnant women are overweight or obese and 8% of women of reproductive age are extremely obese [2]. In England, obesity among women has increased from 16.4% in 1993 to 25.1% in 2012, with similar trends in Scotland and Wales [3]. Obesity in pregnancy has also increased from 9e10% in the early 1990s to 16e19% in the 2000s [4]. A 3-year study of maternal obesity

* Dr Margaret Ann Harper, Consultant Obstetrician and Gynaecologist, Royal Jubilee Maternity Hospital, Grosvenor Road, Belfast BT12 6BB, Northern Ireland, UK. Tel.: þ44 0 28 9063 2150; Fax: þ44 0 28 9063 3700. E-mail address: [email protected].

http://dx.doi.org/10.1016/j.bpobgyn.2014.08.010 1521-6934/© 2014 Elsevier Ltd. All rights reserved.

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in the UK found that 4.99% of pregnant women who gave birth at
24 weeks had a body mass index (BMI) of
35 kg/m2, 2.01% had a BMI of
40 kg/m2 (Class III obesity/morbidly obese) and 0.19% had a BMI of
50 kg/m2 (super-morbid or extreme obesity) [5]. The UK Obstetric Surveillance System (UKOSS) national cohort study of extreme obesity estimated a prevalence of 8.7 cases per 10,000 deliveries (95% confidence interval (CI) 8.1e9.4) or almost one in 1000 [6]. Obesity is over-represented in maternal mortality figures In 2000e2002, 29% of all direct and indirect pregnancy-related deaths in the UK occurred in obese women with a BMI of
30, compared with a 23% incidence of obesity in the general population [7]. This trend continued in the subsequent two triennia where 27% of the women who died from direct or indirect causes had a BMI of
30 kg/m2 [8,9]. The 2003e2005 Confidential Enquiry into Maternal Deaths (CEMD) report observed that obesity was especially predominant among the women who died from thromboembolism, sepsis and cardiac disease; for some extremely obese women, appropriate equipment was not readily available or their weight caused difficulties in moving, resuscitation or surgical access [8]. This report made several recommendations including pre-pregnancy counselling and weight loss, public health messages, better statistical information about the prevalence of obesity and development of a national guideline [8]. The Centre for Maternal and Child Enquiries (CMACE)/ Royal College of Obstetricians and Gynaecologists (RCOG) Joint National Guideline for the Management of Women with Obesity in Pregnancy published in March 2010 will hopefully reduce obesity-related maternal mortality and morbidity [4]. Obesity contributes to maternal and foetal morbidity Obesity is associated with an increased incidence of complications and adverse outcomes at all stages of pregnancy and in the puerperium. These include miscarriage, venous thromboembolism (VTE), pre-eclampsia, gestational diabetes mellitus (GDM), dysfunctional labour, induction of labour, operative vaginal delivery, caesarean section, general anaesthesia, post-partum haemorrhage and wound infections [4,10,11]. For the foetus, congenital anomalies, placental problems, prematurity, large-for-gestational-age babies, stillbirth, neonatal death and lower rates of breastfeeding are more common, and the children of obese women are more likely to become obese themselves [4,10,11]. In the UKOSS study of women whose BMI was
50 kg/m2, extreme obesity was associated with increased risks of pre-eclampsia, gestational diabetes, preterm delivery, caesarean section, general anaesthesia and intensive care unit admission; complications tended to be greater in those with the highest BMIs although there were no maternal deaths among the 665 women studied [6]. How can these risks be minimised? Identifying women at risk The first, crucial step is to identify obese women as early as possible so that a management plan for antenatal care, delivery and afterwards can be made. Obesity in pregnancy is usually defined as a BMI of
30 kg/m2 at the first antenatal (booking) visit [4]. All pregnant women at their booking visit, which should ideally take place by 10 weeks of gestation, should have their height and weight measured accurately using appropriate equipment (not a ‘guesstimate’ or figures provided by the woman in lieu of actual measurement), their BMI calculated and a record made in their clinical notes and electronic patient record [4,12]. A BMI of
30 kg/m2 should trigger an individualised care plan designed to optimise well-being and minimise risk. A simple checklist commenced and placed in the woman's notes at booking can be a useful aide-memoire for the busy midwife or clinician (Fig. 1). Who should care for obese women in their pregnancies? The type of antenatal care should be decided at the booking visit, taking into account the degree of obesity and any pre-existing risk factors. Women with a booking BMI of
35 kg/m2 are recommended to

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Fig. 1. Antenatal care for women with a BMI of
30 kg/m2 in pregnancy: Example of a checklist to be commenced at booking.

be under surveillance during pregnancy in accordance with the Pre-eclampsia Community Guideline [4,13]. This guideline advises that women with a booking BMI of
35 kg/m2 who have no other risk factors for pre-eclampsia can be monitored in the community, but if they have one or more additional risk factors for pre-eclampsia they should be referred early in pregnancy to a specialist [13]. However, Saving Mothers

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Lives 2006e2008 advises that women with a BMI of
35 kg/m2 are unsuitable for midwifery-only care and should be seen in pregnancy by a consultant obstetrician as obesity is an important risk factor for thromboembolism [9]; the National Institute for Health and Care Excellence (NICE) Clinical Guideline on Intrapartum Care advises that women with a BMI of
35 kg/m2 should give birth in a consultant-led unit with appropriate neonatal services as they are at a higher risk of complications, such as shoulder dystocia and post-partum haemorrhage, which require immediate obstetric intervention [14]. Most maternity hospitals do not have the resources to provide a specialist antenatal clinic, so all obstetricians, midwives and general practitioners (GPs) need to be familiar with the specific issues surrounding obesity in pregnancy, and clear policies and guidelines should be available in all antenatal clinics [4]. Managing nutrition and weight gain in pregnancy Dieting during pregnancy is not recommended as it may harm the health of the unborn child [15], but it is important to offer advice and support to avoid excessive weight gain. Women with a BMI of
30 kg/m2 should be offered at the booking appointment a referral to a dietitian or an appropriately trained health professional for assessment and personalised advice on healthy eating and how to be physically active [15]. Small but increasing numbers of women are becoming pregnant after bariatric surgery; this does reduce their risk of obesity-related complications but they may need nutritional supplementation with iron, calcium, folate and vitamins D and B12, and may need their gastric band surgically adjusted during pregnancy [2]. Congenital anomalies are more common A systematic review found that obese women, compared with mothers of normal BMI, had a significantly increased risk of pregnancy affected by neural tube, cardiovascular, orofacial, anorectal and limb reduction anomalies, whereas the risk of gastroschisis was significantly reduced [16]. The suggested mechanisms included: undiagnosed diabetes and hyperglycaemia, as obesity has similar metabolic abnormalities to diabetes; nutritional deficiencies; and underdetection of structural anomalies due to difficulties in ultrasound visualisation, resulting in fewer terminations and increased birth prevalence. As gastroschisis is more common in young women, its decreased risk was attributed to the correlation between obesity and increasing maternal age [16]. In a study of maternal obesity and ultrasound detection of foetal anomalies, there was a significant failure to detect structural anomalies, especially cardiac anomalies, in obese women, which increased significantly with increasing maternal BMI (p ¼ 0.001), and in women with pregestational diabetes (p < 0.001) [17]. No association has been described between maternal obesity and the prevalence of Down syndrome until a recently published 16-year Swedish study of 1,568,604 women, many of whom did not have prenatal screening, found maternal obesity in early pregnancy to be associated with an increased risk of Down syndrome in the newborn; however, prenatal screening with combined ultrasound and biochemistry appeared to be equally effective irrespective of BMI. [18] Strategies to maximise the detection of foetal structural anomalies in obese women include using high-definition ultrasound equipment, a comfortably full maternal bladder to improve visualisation, if necessary repeating the scan a few weeks later and, in women with higher BMIs, considering a transvaginal anatomy scan in the early second trimester. Preventing congenital anomalies Weight reduction before or between pregnancies will help to reduce the incidence of congenital anomalies and other risks associated with obesity. Bariatric surgery before pregnancy does not seem to affect the risk of congenital malformations [19]. There is little information about the teratogenic effects of anti-obesity drugs. The UK teratology information service advises that orlistat (Xenical), the only anti-obesity drug currently listed in the British National Formulary, should be discontinued as soon as pregnancy is diagnosed, as it may impair the absorption of fat-soluble vitamins and there are theoretical concerns that rapid weight loss during pregnancy may restrict nutrient availability to the foetus

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[20,21]. Optimising the control of existing diabetes prior to conception reduces the risk of congenital malformations [22]. Periconceptual folic acid supplementation reduces the risk of the first occurrence as well as the recurrence of neural tube defects [23]. As women with a BMI >27 kg/m2 have lower folate levels, even after controlling for folate intake, compared with women with BMI 40 kg/m2 [9]. Obesity was one of the main risk factors for antenatal pulmonary embolism (aOR 2.65, 95% CI 1.09e6.45) in the UKOSS caseecontrol study between February 2005 and August 2006 [31].

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VTE has been the leading cause of direct maternal mortality in the UK in almost all triennia since the Confidential Enquiries into Maternal Deaths began in 1952. Many of these deaths were preventable. Concern about the high number of maternal deaths after caesarean section in the early 1990s led to recommendations for post-operative thromboprophylaxis that reduced the number of deaths from VTE [32]. Subsequent guidelines recommended thromboprophylaxis for those with moderate or high risk factors after vaginal delivery and antenatally [33]. The effect of these guidelines has already been seen in the most recently published triennium (2006e2008) where maternal deaths from thrombosis and thromboembolism had fallen significantly to 18 (maternal mortality rate (MMR) 0.79 per 100,000 maternities, 95% CI 0.49e1.25) compared with 41 (MMR 1.94 per 100,000 maternities, 95% CI 1.43e2.63) in the previous triennium [9]. The number of deaths from cerebral venous thrombosis also fell in 2006e2008; cerebral venous thrombosis has similar risk factors to pulmonary embolism and both women who died from this cause were morbidly obese [9]. Despite all the recommendations for risk assessment and thromboprophylaxis in the series of guidelines produced since 1995, thromboembolism has remained a leading cause of direct maternal mortality. Although it has long been recognised that obesity is an important risk factor for VTE, it is only in the most recent version of the RCOG guideline that recommendations have been made to increase the dose of thromboprophylaxis depending on body weight (Table 1), so further reductions in maternal mortality from VTE may be seen in future. Much more can still be done e inadequate risk assessment, inadequate thromboprophylaxis, failure to investigate chest symptoms and failure to ensure multidisciplinary care when it would have been appropriate contributed to some maternal deaths from VTE in 2006e2008 [9]. Raising awareness of and implementing the guidelines are important. Women with a booking BMI of
30 kg/m2 should undergo a documented risk assessment for thromboembolism at their first antenatal visit; where antenatal thromboprophylaxis is appropriate, it should begin as early in pregnancy as practical as the pregnancy-related risk of VTE is present even in the first trimester [30]. A VTE risk assessment should be repeated each time a woman is admitted to a hospital, including on admission to a labour ward and if admitted to a postnatal ward [30]. When thromboprophylaxis is indicated, low-molecular-weight heparin (LMWH) should be prescribed in doses appropriate for maternal weight (Table 1) [30]. Postnatally, women with a BMI of
30 kg/m2 should be encouraged to mobilise early after childbirth to reduce their risk of thromboembolism. If there are any additional risk factors for thromboembolism, they should be considered for LMWH for 7 days after delivery, and women who have two or more additional persisting risk factors should be given graduated compression stockings in addition to LMWH. All women with a BMI of
40 kg/m2 should be offered postnatal thromboprophylaxis regardless of their mode of delivery [30]. If VTE is suspected, prompt investigation is warranted. The signs and symptoms of VTE include calf pain, tenderness and swelling, tachycardia, breathlessness, chest pain and haemoptysis and, for cerebral thrombosis, persistent headache or neurological symptoms. LMWH in a therapeutic dose appropriate to body weight should be commenced immediately while awaiting investigations and results, and should not be discontinued until VTE has been ruled out. RCOG Clinical Green-top Guideline 37b outlines the investigation and management of VTE [34]. Pre-eclampsia is more common Obesity is associated with an increased prevalence of pre-pregnancy hypertension and an increased risk of pre-eclampsia [11]. The Pre-eclampsia Community Guideline advises that women with a booking BMI of
35 kg/m2 who have no additional risk factors for pre-eclampsia can be monitored in Table 1 Weight-specific dosage advice for thromboprophylaxis in women with maternal obesity [30]. Weight (kg)

Enoxaparin

Dalteparin

Tinzaparin

91e130 131e170 >170

60 mg daily 80 mg daily 0.6 mg/kg/day

7500 units daily 10,000 units daily 75 units/kg/day

7000 units daily 9000 units daily 75 units/kg/day

All of the above may be given in two divided doses.

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the community at a minimum of 3-week intervals between 24 and 32 weeks of gestation, and then at a minimum of at least every 2 weeks from 32 weeks until delivery. However, if they have one or more additional risk factors for pre-eclampsia, they should be referred to a specialist early in pregnancy [4,13]. The additional risk factors for pre-eclampsia include: first pregnancy, age
40 years, multiple pregnancy, pre-eclampsia in a previous pregnancy or a first-degree relative,
10 years since last baby, diastolic blood pressure of
80 mm Hg at booking, proteinuria at booking of
1þ on more than one occasion or
0.3 g/24 h, anti-phospholipid antibodies and pre-existing hypertension, renal disease or diabetes [13]. Women with higher BMIs tend to have larger upper arm circumferences, and it is important to use an appropriate size of the sphygmomanometer cuff to avoid measurement errors due to using too small a cuff [4,12]. The NICE Clinical Guideline on Hypertension in Pregnancy advises women who have a booking BMI of 35 kg/m2 and who have one or more additional moderate risk factors for pre-eclampsia to take 75 mg of aspirin daily from 12 weeks until the birth of the baby [35]. Plan ahead for labour and delivery Women with obesity, compared with women of a healthy weight, have a higher incidence of intrapartum complications, and it is recommended that women with a BMI of
30 kg/m2 be referred during pregnancy to a consultant obstetrician for an informed discussion about how these risks can be minimised [4]. This should include discussion about induction of labour, which carries a higher chance of caesarean section, the increased likelihood of technical difficulties during operative procedures and the possibility that a general anaesthetic may be necessary for caesarean section. Women with a BMI of
35 kg/m2 are advised to give birth in a consultant-led unit with appropriate neonatal services as they are at a higher risk of complications, such as shoulder dystocia and post-partum haemorrhage, which require immediate obstetric intervention [14]. Intrapartum complications include slow progress in labour, technical difficulties in siting venous access and regional anaesthesia and in monitoring the foetal heart, shoulder dystocia, emergency caesarean section, difficult surgery and primary post-partum haemorrhage. If general anaesthesia is necessary, there is an increased risk of difficult intubation, aspiration of gastric contents and postoperative atelectasis, and obese women are more likely to have other medical conditions such as hypertension and ischaemic heart disease [4]. The possible scenario of a morbidly obese woman who needs an immediate caesarean section in the middle of the night with only relatively inexperienced doctors on site is a very high-risk situation. To reduce risks for obese women in labour, all pregnant women with a booking BMI of
40 kg/m2, who are at the highest risk, should undergo an antenatal assessment with an obstetric anaesthetist so that potential risks can be discussed and an anaesthetic management plan be clearly documented in the clinical notes [4]. Many maternity hospitals do have a dedicated obstetric anaesthetic antenatal clinic, and if there are concerns, the anaesthetic staff should also see women whose BMI is < 40 kg/m2 for antenatal assessment. It is recommended that an obstetrician and an anaesthetist at Specialty Trainee year 6 and above (or equivalent) be kept informed and be readily available when a woman with a BMI of
40 kg/m2 is admitted to the labour ward or if operative intervention is anticipated, including a physical review of the patient and attendance at any operative vaginal or abdominal delivery; that if an epidural is desired, it should be sited early on in labour; and that venous access should also be established early [4]. An important consideration for the safe manual handling of very obese women is the availability of appropriate beds, theatre tables and other equipment. This requires assessment and planning well in advance of labour and delivery. Most delivery units already have larger beds and theatre tables capable of safe load bearing for heavier patients, and have other equipment such as large sphygmomanometer cuffs, larger sizes of thromboembolic-deterrent stockings (TEDS), pneumatic compression leggings for VTE thromboprophylaxis, hoists and other equipment for safe patient transfer, but, if not, this needs to be addressed in advance. It is recommended that women with obesity in pregnancy have their weight remeasured in the third trimester to allow appropriate plans

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to be made for equipment and personnel during labour and delivery, and that operating theatre staff be kept informed [4]. Tissue viability and the increased risk of pressure sores when immobile is another concern for very obese women. Women with a BMI of
40 kg/m2 should undergo a documented assessment using a validated formal scoring system so that appropriate plans can be made for body position and repositioning schedules, skin care and support surfaces for times when they may be relatively immobile, for example, during surgery or if confined to bed [4]. Managing labour, delivery and third stage to minimise risk Induction of labour carries the risk of failed induction and emergency caesarean section, and there is no reason to induce labour or perform a caesarean section because of obesity alone e normal birth should be encouraged and induction of labour is best reserved for those women with other obstetric or medical complications that require induction [4]. When there is a history of previous caesarean section in women with a BMI of
30 kg/m2, an individual assessment of mode of delivery is advised [4]. For some women, an elective caesarean section for obstetric or medical reasons is the most appropriate choice, but for others a trial of labour in the hope of achieving VBAC (vaginal birth after caesarean section) may be considered. The circumstances leading to the previous caesarean, any associated complications, the current situation including the ultrasound-estimated foetal weight, the increased risks of unsuccessful VBAC, anaesthetic and surgical difficulties in obese women and, for morbid obesity, the increased risks of uterine rupture and neonatal injury need to be taken into consideration, discussed with the woman and documented in her notes before reaching a decision on the planned mode of delivery [4]. Once in established labour, women with morbid obesity require extra attention to pressure areas and to monitor and ensure normal progress in labour, and closely monitor the foetal heart. Continuous midwifery care throughout labour is advised; if there is difficulty in auscultation of the foetal heart, a foetal scalp electrode should be attached and, if necessary, an ultrasound scan can be performed [4]. Obesity is associated with an increased risk of post-partum haemorrhage [10]. Active management of the third stage of labour is recommended for women with a BMI of
30 kg/m2 as it reduces the duration of the third stage, reduces post-partum haemorrhage, reduces the need for oxytocic drugs and blood transfusion and reduces the risk of post-partum anaemia [4]. Minimising surgical and infection risks Surgical procedures can be technically challenging in obese women. Vaginal procedures such as operative delivery or repair of vaginal tears may be made more difficult by dense folds of fatty tissue obscuring the operator's vision and access. Before starting the procedure, explanation, reassurance and good analgesia will help to relax the patient; she should be placed as comfortably as possible in lithotomy or any other suitable position, if necessary with padding placed around her calves to reduce pressure and minimise the risk of deep venous thrombosis. Optimising the position of the theatre light and the help of one or two assistants to retract tissues and hand instruments will ensure the best view of and access to the operative field. Senior help should be requested early if there is any difficulty. Surgical access for caesarean section can be difficult and should be anticipated before embarking on the procedure. The surgeon and anaesthetist should be competent; as noted earlier, an obstetrician and an anaesthetist at Specialty Trainee year 6 and above (or equivalent) should be informed and readily available when a woman with a BMI of
40 kg/m2 is admitted to the labour ward or if operative intervention is anticipated, including attendance at any operative vaginal or abdominal delivery [4]. Irrespective of the time of day or night, the obstetric and anaesthetic consultants on duty for the labour ward should be kept informed and called promptly to the scene if problems are anticipated or arise during the operation. As for vaginal procedures, good light and competent assistants are important, and extra help may be needed to hold back tissue if there is an overhanging fatty apron (panniculus). The operative procedure should be performed using the principles described in the NICE Clinical Guideline No. 132, [36] but it

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may be necessary to modify the surgical incision in very obese women as a low transverse supra-pubic incision will be more prone to infection if it lies in the moist anaerobic conditions under the panniculus [37]. A higher transverse incision avoiding this area or a midline vertical incision made after retracting the panniculus may be better alternatives depending on the clinical circumstances. For transverse incisions, if there is > 2 cm of subcutaneous fat, the subcutaneous tissue space should be sutured to reduce the risk of wound infection and wound separation [4]. Dehiscence and incisional hernias are more likely to occur in vertical incisions; to reduce their incidence and the risk of infection, a mass closure technique using slowly absorbable continuous sutures [36], staples to close the skin and leaving an intrafascial drain in situ until drainage is < 50 ml/24 h are advised [37]. Women with a BMI of
30 kg/m2 have an increased risk of infection; as recommended for all women regardless of BMI, at the time of caesarean section, they should be offered prophylactic antibiotics effective against endometritis, urinary tract and wound infections [36]. All 10 women who died from genital tract sepsis following caesarean section in 2003e2005 were overweight, two were morbidly obese and one was a gestational diabetic [8]. All 10 women were given antibiotic prophylaxis at operation [8] and, in addition to close observation using a modified early obstetric warning score (MEOWS) chart to detect early signs of sepsis [9], consideration should be given to prolonging the course of antibiotic prophylaxis after caesarean section in morbidly obese women. Giving prophylactic antibiotics before, rather than after, the skin incision reduces the risk of maternal infection and no effect on the baby has been demonstrated; however, co-amoxiclav should not be used when giving antibiotics prior to the skin incision [36]. Irrespective of BMI, antibiotic prophylaxis is recommended for all women at the time of abortion [38], for preterm prelabour rupture of membranes [39], and following third- and fourth-degree anal sphincter tears [40]. Although there are insufficient data to recommend routine antibiotic prophylaxis for operative vaginal delivery [41,42] or manual removal of retained placenta [43], it should be considered in obese women, particularly if the procedure has been difficult. Reducing post-partum complications After delivery, obese women remain at risk, and a close watch should be kept for any signs of infection or thromboembolism and vital signs checked if there are any concerns. The woman's thromboembolism risk assessment should be reviewed and LMWH commenced if indicated. Following up on antenatal advice, women with a booking BMI of
30 kg/m2 should be offered a structured weight-loss programme and nutritional and lifestyle advice and encouraged to lose weight, which will reduce their risks in future pregnancies [4,15]. If gestational diabetes has been diagnosed, a test of glucose tolerance should be performed 6 weeks after delivery. Even if this test is normal, women with a booking BMI of
30 kg/m2 who had gestational diabetes should have regular follow-up with their GP to screen for the development of type 2 diabetes, as they have an increased risk of developing this condition compared with women who were normoglycaemic during pregnancy [44]; these women should also have annual screening for cardiometabolic risk factors and be offered lifestyle and weight management advice [4]. Summary Pregnant women who have a booking BMI of
30 kg/m2 are at an increased risk of a wide range of antenatal, intrapartum, post-partum and neonatal complications, including maternal mortality, and the risks increase with increasing BMI. Ideally, obese women should aim to lose weight prior to conception. This depends on informing and advising women of childbearing age about the risks of obesity in pregnancy, through public health initiatives and the media, and as opportunities arise when they attend primary care, family planning or at diabetic clinics. Identification of obesity at booking allows an appropriate choice of antenatal care and place of delivery, the opportunity to offer nutritional and lifestyle advice, to plan for labour and delivery, good post-partum management including thromboprophylaxis and ongoing plans for weight reduction to minimise risks in future pregnancies and in later life. Adherence to advice in the various guidelines that relate to obesity in pregnancy and its complications will help to reduce morbidity and mortality in obese mothers.

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Practice Points  Women with a booking BMI of
30 kg/m2 should be identified at booking and have a detailed management plan for pregnancy and delivery  Women with a booking BMI of
30 kg/m2 should be screened for gestational diabetes at 24e28 weeks using the 2-h 75-g oral glucose tolerance test  Women with a booking BMI of
40 kg/m2 should have an antenatal appointment with an obstetric anaesthetist  Obesity alone is not an indication for induction of labour  Senior obstetricians and anaesthetists should be closely involved with the care of obese women who are in labour or undergoing caesarean section  Where thromboprophylaxis is indicated, the dose of LMWH should be adjusted according to body weight

Research Agenda  The role of vitamin D supplementation  Factors influencing the increased incidence of caesarean section in obese mothers  Management of pregnancy following bariatric surgery

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