Obesity and exercise in pregnancy Flashcards
What % of pregnant women are overweight or obese?
45%
What is the % risk of maternal severe morbidity and mortality for class III obese women in pregnancy?
2%
List effects of obesity on maternal antenatal outcomes:
• Miscarriage • Increased risk of multiple gestation • Chest, genital tract, and urinary infections • Cholecystitis • Depression • Diabetes (gestational and type II) 7% • Gestational hypertension and preeclampsia 10% • Maternal mortality • Obstructed labour • Obstructive sleep apnoea • Preterm birth10% Thromboembolic disease
List effects of obesity on maternal labour and postpartum outcomes:
Labour: • Caesarean section 52% • Failed induction of labour • Induction of labour for prolonged pregnancy • Failed VBAC • Operative and complicated vaginal birth • Difficult surgical access • PPH
Postpartum:
• Reduced breastfeeding
• Surgical site infections
List effects of obesity on anaesthetic outcomes:
- Difficulty intubating and maintaining an adequate airway
- Difficulty intravenous access
- Regional anaesthetic more difficult to site
- Difficulty with positioning
- Difficulty monitoring blood pressure
- Increased failure of epidural analgesia during labour
- Increased risk of regurgitation and aspiration of stomach contents
- Unpredictable spread of local anaesthetic
- Increased need for postpartum ICU/HDU admission
List effects of obesity on fetal and neonatal outcomes:
- Increased risk of failure of NIPT
- Suboptimal ultrasonography
- Increased risk of undetected fetal structural abnormality
- Congenital malformations including neural tube defects, congenital heart disease, omphalocele, cleft lip and palate
- Suboptimal electronic fetal monitoring
- SGA 20%
- Macrosomia 20%
- Low Apgar score
- Admission to neonatal intensive care units
- Shoulder dystocia
- Stillbirth 2%
• Long term neonatal outcomes:
• Neonatal body composition
• Infant weight gain
Obesity
How do you calculate BMI?
BMI = weight (kg) / height (m) squared.
Units: kg/m2
Outline your preconceptual counselling with a woman who is obese:
- Discuss effects of obesity on pregnancy outcomes (maternal, anaesthetic and fetal).
- Encourage weight loss prior to conception. Refer to bariatric surgery if needed.
- Explain increased risk of NTDs and prescribe high dose folic acid.
- Prescribe iodine
If hx of bariatric surgery:
- Dietician input
- Advice not to conceive until at least 12-24 months after.
Outline your antenatal counselling with a woman who is obese about antenatal care (not including IOL/delivery):
First trimester:
- Supplementation: high dose folic acid 5 mg, iodine.
- General advice: diet, GWG, exercise.
- PET education (increased risk 10%) and prevention with low dose aspirin and calcium supplementation.
- Increased risk of depression: screen antenatally.
Second trimester:
- NIPT: increased risk of no-call results. 5% if class I, 10% if class II obesity.
- Early GDM screening: if normal repeat at 26-28 weeks.
- Anatomy scan as increased risk of congenital malformations including NTDs, cleft lip and palate, congenital heart disease, omphalocoele. Refer to MFM if extremely obese as can miss abnormalities.
- Midtrimester bloods: Hb, iron stores; supplement as needed.
- Regular MSUs for bacteriuria and PET/proteinuria.
- Monitor FMs as increased risk of stillbirth.
- Serial growth scans from 28 weeks as increased risk of SGA and stillbirth.
- Influenza vaccine as increased risk of morbidity.
Third trimester:
- Serial growth scans 28, 32, 36 weeks.
- Anaesthetic review/referral.
- Discussion of timing of delivery/IOL and mode of delivery.
What recommendations are there regarding timing and mode of delivery for obese women?
What would you outline in your VBAC discussion with an obese woman?
Evidence for IOL <40 weeks for:
- Extreme obesity BMI>50 at 38-39 weeks as risk of stillbirth increases dramatically after 39 weeks.
- Class 3 obesity at 39 weeks.
Mode of delivery: consider comorbidities, fetal macrosomia etc.
- Risk of EmCS 52% for class 3 obesity.
- Elective CS may be appropriate for some.
VBAC:
- Likelihood of success lower (20%) for obese women.
- Associated with higher risk of serious neonatal and maternal complications.
- High risk of IOL failure (of doesn’t labour spontaneously)
What is the adjusted hazard ratio for stillbirth and class of obesity?
Class 1 (BMI 30-34.9): 1.7 Class 2 (BMI 35-39.9): 2.0 Class 3 (BMI >=40): 2.5 Extreme obesity (BMI >=50): 3.1
What special cares or precautions would you take with an obese woman in labour?
- Confirm fetal presentation with ultrasound.
- IVL early.
- CEFM (may need FSE).
- Prolonged labour especially long latent phase: may need longer and more syntocinon to achieve vaginal delivery.
- Anticipate shoulder dystocia.
- PPH risk: active third stage management.
- Inform anaesthetist on call
- Inform OT if >120kg so can prepare for appropriate equipment and support
What special cares or precautions would you take with an obese woman needing obstetric theatre?
- Inform theatre if >120 kg.
- Vagina cleansing with chlorhexidine.
- Increased cefazolin dose 3g if >120kg
- Skin incision (Pfannensteil vs tranverse above panniculus vs midline)
- Panniculus retractor: tape.
- Closure: looped PDS rectus sheath; subcutaneous tissue closure; negative pressure dressing.
What are the recommended gestational weight gain (GWG) ranges for various BMI classes?
- BMI <18.5: 12-18 kg
- BMI 18-24.9: 11.5-16 kg
- BMI 25-29.9: 6-11 kg
- BMI >30: 5-9 kg
What are the exercise recommendations for pregnancy?
- What: aerobic exercise, intensity dictated by baseline fitness.
- When: most days
- How: 30 mins at a time
- Avoid: care with weight bearing, frequent changes in direction; avoid jumping.
- Contraindications: fetal growth restriction, poorly controlled thyroid disease or anaemia
- Cautions: CVD, poorly controlled asthma, poorly controlled diabetes, joint/mobility issues.
