Obesity, Bariatric Surgery & Pregnancy
Pat O’Brien
Institute for Women’s Health
University College London Hospitals
Obesity & Pregnancy
Bariatric Surgery Adjustable Gastric Banding Proximal Gastric Bypass Sleeve Gastrectomy
Bariatric Surgery
United States • x 8 from 1998 to 2005 (12,000 113,000) • Of those aged 18-45 years old, 83% women Maggard et al, 2009
United Kingdom • 40% from 2006 to 2007 in NHS (1951 2724)
– 78% women Information Centre for Health & Social Care, 2009
• Private: 74% from 2008 to 2009 (to 12,848)
Singleton births in Sweden 1992-2009
Roos N et al. BMJ 2013;347:f6460
Bariatric Surgery • BMI > 40 or • BMI 35 – 40 with health
problems • Type 2 DM • Cardiovascular
NICE (2006)
If BMI ≥ 38 (♀): surgery better than non-surgical measures
Bariatric Surgery
Profound effects on glucose homeostasis
• 50% complete ‘remission’ of T2DM = HbA1c <6.0% off all drugs for at least 1year (ADA consensus criteria, Buse et al, Diabetes Care 2011)
• Majority discontinue anti-DM drugs prior to leaving hospital
• Improvement occurs before significant weight loss
Bariatric Surgery
Restrictive versus Malabsorptive
Reversible versus Irreversible
Gastric Banding Laparoscopic Adjustable Gastric Banding (LAGB)
• First described in mid-1980’s
• First laparoscopic insertion Belgium 1993
• Pouch 20-40 mls = mouthful
Gastric Banding Laparoscopic Adjustable Gastric Banding (LAGB)
• Restrictive • Reversible • No effect on absorption
– though intake may be ↓ (e.g. Iron)
• Calorie intake ↓ by 50 – 60% • No ‘feeling of fullness’
Gastric Banding Management in pregnancy
• Deflate in first trimester food intake
• heartburn – deflation may help • Deflate before delivery - ? pressure
Gastric Banding Complications
• Obstruction: fundus moves through band • Erosion • Slips • Tube leaks • Port problems • If removed, may be scarring
– Subsequent bypass more difficult – Tend to gain weight again
(no psychological change)
25% will need removal “Expect it to last 10 years”
Gastric Bypass Roux-en-Y (RYGBP)
• Originally ulcers/cancer • Combination of restriction and
malabsorption • Stomach pouch 20-40mls restrictive
empties into mid-jejunum (bypasses 50-100 cm) Also delayed mixing with bile & pancreatic juices
Note: Amount of bowel bypassed does not seem to be α weight loss
Another powerful effect: • Early satiety ↓↓ appetite ↓ food cravings
Secondary to intestinal hormone Peptide YY-36 (PYY)
Gastric Bypass Roux-en-Y (RYGBP)
Gastric Bypass Micronutrient effects
• Iron – ↓ stomach acid ↓ ferric ferrous
• Vitamin B12 – ↓ intrinsic factor
• Calcium – Duodenal exclusion absorption ↓↓
• Vitamin D – Fat soluble (may be deficient even before surgery)
• Vitamin A – Difficult to process samples false low measurements
Biliopancreatic Diversion (BPD)
• Introduced in 1979 • Part of stomach resected • Distal small intestine
connected to stomach • Restriction not major
– Normal diet possible • Bypasses duodenum &
jejunum
Biliopancreatic Diversion (BPD)
• Alimentary limb • Biliopancreatic limb • Food meets bile & pancreatic juices
in “Common channel” truly malabsorptive • ↓ absorption
• Fats • CHO • Fat-soluble vitamins (A,D,E,K)
Proteins absorbed by mass effect, even in ascending colon
Laparoscopic Sleeve Gastrectomy
• Small reservoir • Cardiac sphincter intact
Ghrelin • hunger • α time since last food • Gastric peptide • Produced mainly in fundus
• Swedish registry 1992 - 2009 • 1.7 million singleton pregnancies • Bariatric surgery 2,562 • Matched controls 5:1
Singleton births in Sweden 1992-2009
Roos N et al. BMJ 2013;347:f6460
Control Group 1
Roos N et al. BMJ 2013;347:f6460
Pregnancy outcomes after Bariatric surgery
PTB < 37 weeks Iatrogenic PTB Spontaneous PTB PTB 32-37 weeks PTB < 32 weeks SGA (<2.5th centile) LGA (>97.5th centile)
9.7 4.5 5.2 7.7 2.2 5.2 4.2
6.1 2.5 3.6 5.1 1.0 3.0 7.3
1.7 1.8 1.5 1.6 2.0 2.0 0.6
Bariatric Controls OR
All p values <0.001
Control group Normal
Subgroup analysis
Mortality: No difference
Stillbirth Neonatal mortality
0.79 0.28
0.60 0.26
0.32 0.86
Bariatric Controls P value
Control Group 2
Matched with women eligible for bariatric surgery (BMI ≥ 35)
Post-surgery No surgery P-value n 2,496 12,126 Mean BMI 32.5 38.5 <0.001 Preterm Birth 236 (9.5%) 863 (7.2%) <0.001 SGA 128 (5.2%) 313 (2.6%) <0.001
Conclusions
• Increasingly common in pregnancy • High risk group • Risk of Preterm Birth and SGA • Mechanism unknown - ?micronutrients • Does micronutrient supplementation help?
• Band: deflate in early pregnancy • Bypass: malabsorption
Thank you
Top Related