Obs&gyn: Obesity Flashcards
How to calculate BMI?
Body Mass Index (BMI)
Weight (kg)/ Height2 (m2)
BMI ranges
- BMI of 25-30: Overweight
- BMI 30-34.9: Class 1 Obesity
- BMI 35-39.9: Class 2 Obesity
- BMI 40+: Class 3 or Morbid Obesity
How does obesity may cause a disease?
White fat around viscera sets up inflammation and cell death and causes disease
What’s Leptin?
Leptin
- produced by adipose tissue
- mediates long term appetite controls
- encourage us to eat more when fat stores are low, and less when storage is high
What’s Ghrelin?
Ghrelin
- produced by the empty stomach
- modulating short term appetite
- encouraging us to eat when the stomach is empty, and stop when the stomach is stretched
By use of what pathways leptin and ghrelin produce their effects on appetite?
- Leptin and ghrelin control the appetite through action on the central nervous system
- Act on the paraventricular and arcuate nuclei of the hypothalamus through several pathways
What (3) hormones adipose cells produce?
- Adiponectin → regulates fatty acid and glucose metabolism - levels are lower in obesity, which is related to insulin resistance
- Oestrogen
- Leptin - note levels of leptin are higher, but obesity leads to Leptin resistance
Complications of obesity
What BMI of >30 in pregnancy increases the risk of?
- Thrombosis
- Gestational Diabetes - 3 fold increase
- Pre-eclampsia - with BMI of 35 the risk is double that of a woman with a BMI of 25
- Neural tube defect
- Miscarriage - increases from 20% to 25%
- Increased birth weight - chances of a baby weighing more than 4kg are increased from 7% to 14%
- Stillbirth - risk increased from 1 in 200 to 1 in 100
- Increased risk of baby developing obesity or diabetes in later life
Risks of BMI >40 in pregnancy and labour
With a BMI of more than 40:
- Increased risk of prematurity
- Labour dystocia
- Shoulder dystocia
- Emergency caesarean section
- Intraoperative complications, including bleeding
- Postoperative complications, including wound infection
- Anaesthetic complications, particularly with general anaesthesia
- Postpartum haemorrhage
What advice to give for a woman of BMI of 30 or more wants to conceive?
- advice on weight and lifestyle should be given to all women of childbearing age
- support to lose weight prior to conception for all women with a BMI of 30 or more
- BMI of 30 or more should be advised to commence 5mg Folic Acid supplementation at least a month before conception and continuing during the first trimester of pregnancy
• BMI of 30 or more should be advised to commence 10 micrograms Vitamin D supplementation daily throughout pregnancy and while breastfeeding
Do we need to refer a pregnant obese woman?
Women with a BMI of 30 or more should be referred to a consultant obstetrician
When during pregnancy should we measure maternal weight and height?
- Weight and height should be measured and BMI recorded at booking visit
- Re-measurement of maternal weight in the third trimester will aid planning with regard to equipment and personnel
Considerations for maternal BMI >35 and pre-eclampsia
Women with a BMI of 35 or more have an increased risk of pre-eclampsia.
Assess additional risk factors and commence low dose aspirin
When and for whom do we do OGTT in pregnancy?
Women with a BMI of 30 or more should have a 2 hour 75g oral glucose tolerance test at 24-28 weeks
The anaesthetic risk for women with BMI 40 or more
Women with a BMI of 40 and above should have an antenatal consultation with an obstetric anaesthetist to assess and discuss potential risks with IV access and regional and general anaesthesia
- Epidural re-site and failure rates higher
- Higher risk of gastric content aspiration, difficult intubation and postoperative atelectasis with general anaesthesia
- Increased comorbidities including IHD and hypertension
Extra nursing and manual handling considerations for women with BMI of 40 or more
Women with a BMI of more than 40 should have:
- a manual handling and tissue viability assessment
- safe workloads of beds and theatre tables
- appropriately sized TEDS or boots
- plan for body position, repositioning, skin care and support services in women at risk of pressure sores
Potential intrapartum complications in obese women
- Slow progress
- Shoulder dystocia
- Emergency caesarean section
- Increased risk of PPH
- Vaginal Birth After Caesarean (VBAC) can be considered on an individual basis – obesity is a risk factor for uterine rupture
Place of birth for obese women
Women with a BMI of 35 or more should give birth on a consultant led unit with appropriate neonatal services – babies are 1.5 times more likely to require admission to special care
•Duty anaesthetist should be informed when a woman with a BMI of 40 or more is admitted if delivery/theatre is anticipated. Early epidural may be advisable if required
What (extra) interventions woman with BMI of 40 or more may require during labour?
Women with BMI of 40 or more should have:
- continuous midwifery care
- continuous fetal monitoring by CTG recommended, and fetal scalp electrode may be required to adequately monitor baby’s heart rate pattern
- IV access in labour
- Active management of 3rd stage due to increased risk of PPH
How do we manage wound infection risk in women with BMI 30 or more?
Increased risk of wound infection at caesarean with BMI of 30 or more
- prophylactic Abx and consideration of dressing type and use of fat stitch during abdominal closure
Who to test for gestational diabetes?
Screen for GDM at 24-28 weeks with 75g OGTT if any of the following are present:
- BMI above 30 kg/m2
- Previous macrosomic baby weighing 4.5 kg or above
- Previous gestational diabetes (although most units advise BG monitoring from around 14 weeks
- Family history of diabetes (first‑degree relative with diabetes)
- Minority ethnic family origin with a high prevalence of diabetes
- Test opportunistically if Glycosuria of 2+ or above on 1 occasion or 1+ or above on 2 or more occasions during routine antenatal checks
Positive result renges of OGTT in pregnancy
Positive 75g OGTT:
•Fasting plasma glucose level of 5.6 mmol/l
•2‑hour plasma glucose level of 7.8 mmol/l
Management of gestational diabetes
- Advise capillary glucose testing pre-meal and 1 hour postprandial
- refer to Obstetrician and Diabetes team (usually a joint clinic)
- Intervention includes diet control, medication and/or insulin
Chronic hypertension vs gestational hypertension
(definitions)
- Chronic hypertension is present at booking or before 20 weeks or if already being treated for hypertension prior to pregnancy
- Gestational hypertension is new hypertension presenting after 20 weeks without significant proteinuria
Pre-eclampsia vs severe pre-eclampsia
(definitions)
- Pre-eclampsia is new hypertension presenting after 20 weeks with significant proteinuria, or superimposed on chronic hypertension
- Severe pre-eclampsia is pre-eclampsia with severe hypertension with significant proteinuria and/or with symptoms, and/or biochemical and/or haematological impairment
What’s HELLP syndrome?
HELLP syndrome:
- haemolysis
- elevated liver enzymes
- low platelet count
- It’sconsidered a severe variant of pre-eclampsia
What’s eclampsia?
Eclampsia is a convulsive condition associated with pre-eclampsia
Mild HTN in pregnancy ranges
Moderate HTN in pregnancy - ranges
Severe HTN in pregnancy - ranges
Symptoms of pre-eclampsia
- severe headache
- problems with vision, such as blurring or flashing before the eyes
- severe pain just below the ribs
- vomiting
- sudden swelling of the face, hands or feet
*make pregnant women aware of these symptoms and that they should seek immediate medical attention
What’s defined as significant proteinuria?
- Urinary protein:creatinine ratio is greater than 30 mg/mmol (preferred method)
- Validated 24-hour urine collection result shows greater than 300 mg protein
Aspirin prophylaxis for women at high risk of pre-eclampsia
women at high risk of pre-eclampsia to take 75 mg of aspirin daily from 12 weeks until the birth of the baby
What places a woman in high risk of pre-eclampsia category?
- Hypertensive disease during a previous pregnancy
- Chronic kidney disease
- Autoimmune disease such as systemic lupus erythematosis or antiphospholipid syndrome
- Type 1 or 2 diabetes
- Chronic hypertension
Aspirin prophylaxis for woman with moderate risk of pre-eclampsia category
More than one moderate risk factor for pre-eclampsia:
take 75 mg of aspirin daily from 12 weeks until the birth of the baby
Moderate risk for pre-eclampsia
- First pregnancy
- Age 40 years or older
- Pregnancy interval of more than 10 years
- Body mass index (BMI) of 35 kg/m2 or more at first visit
- Family history of pre-eclampsia
- Multiple pregnancy
Obesity increases the risks of which gynaecological cancers?
- Increased BMI reduces risk of premenopausal breast cancer
- Increased risk of ovarian and endometrial cancers
- Increased risk of postmenopausal breast cancer
- 30% of endometrial cancers in the UK are due to overweight and obese BMIs
- Risk of endometrial cancer is increased by x 2-3 (x 6 if morbidly obese)
- Physical activity can reduce endometrial cancer risk by up to 20-30%
- PCOS women have an increased x 4 risk of endometrial cancer pre-menopause related to obesity
What gynaecological conditions early-onset obesity is associated with?
Early onset obesity is associated with:
- Oligomenorrhoea
- Menstrual irregularity
- Anovulation
- Subfertility
- Miscarriage
- Polycystic Ovarian Syndrome
Surgical considerations for obese women
- Laparotomy and Laparoscopy technically more difficult
- Consider robotic surgery in morbidly obese women
- Anaesthetic risks
- Wound infection
- Thromboembolism
Obesity and contraceptive methods
Emergency contraception in obese women
Emergency contraceptives can be used:
- in women of any weight or body mass index (BMI)
- obesity is not a contraindication to any of these methods
