For many patients with obesity, treatment options have been limited to either diet and lifestyle modifications or invasive procedures like bariatric surgery. Endoscopic sleeve gastroplasty presents an effective non-surgical option that is minimally invasive, reversible, and repeatable with quick recovery time.


Obesity is a chronic disease. Compared to people with normal weight, it has been shown that the overweight and obese are at increased risk of developing diabetes mellitus, hypertension, cardiovascular disease, stroke, and obstructive sleep apnoea.1 They are also at higher risk of 13 different types of cancers and increased mortality. Additionally, the quality of life and productivity of obese individuals are shown to be very low.2

Obesity is a multifactorial disease with a complex pathophysiology. It is often considered a self-inflicted problem, and patients with obesity are eschewed away with “eat less and exercise more” advice rather than having a concrete long-term care plan. Studies have demonstrated that individuals delay at least 6 years before consulting a physician for obesity.3

The main treatment goal is to achieve >10-15% total body weight loss to observe improvement in obesityrelated
comorbidities, quality of life, and mortality.4 The current treatment options are either minimally effective, like diet and lifestyle intervention, or more invasive, like bariatric surgery, catering only to 1-2% of eligible patients with obesity.

Endoscopic sleeve gastroplasty (ESG) was developed to break down these barriers and encourage more patients to seek treatment. ESG is a non-surgical endoscopic approach that is an effective, minimally invasive, reversible, and repeatable option for obesity with quick recovery time.


There is increasing public, governmental, and healthcare provider awareness of the alarming rise in the incidence of obesity both in Singapore and internationally. It is estimated that the prevalence of obesity in Singapore is around 11% and is expected to go higher. It has been shown that obesity is the single largest contributor to the nation’s disease burden of diabetes mellitus (73%), and recent analyses estimate that Singapore incurs the third highest direct and
indirect healthcare spending (US$0.4-1 billion) arising from obesity in the ASEAN region.5, 6


ESG is a non-surgical weight loss procedure performed to reduce the size of the stomach in patients with obesity. It is performed using an endoscope fitted with a suturing device at the tip (Figure 1A).

The stomach is inspected first, and then an endoscope fitted with a suturing device is introduced orally. Using the device and accessories, multiple full-thickness sutures are placed inside the gastric wall to make it smaller, like a tube, and reduce its distensibility (Figures 1B and 1C). ESG leads to significant weight loss by enabling patients to feel full quickly after a meal and thus limiting their meal volume. Additionally, it may also delay gastric emptying causing early satiety.7

ESG Suturing DeviceThe ESG Procedure
The procedure takes approximately 60 minutes, and the patient needs to stay in the hospital for 24 hours for observation. As ESG is minimally invasive, the risk of complications is low, and patients can quickly return to their daily activities.

Like any weight loss procedure, commitment to a healthy lifestyle is required for long-term success. When combined with lifestyle modification, ESG results in about 15% to 20% total body weight loss at 12 to 24 months.8


ESG is suitable for:

  • Patients with obesity (BMI ≥27.5 kg/m2)
  • Patients who do not qualify for bariatric surgery
  • Patients who decline or are unsuitable for bariatric surgery
  • Patients who are unsuccessful in achieving or maintaining weight loss after diet and lifestyle modification alone


The ESG procedure is performed under general anesthesia in an endoscopy unit. A representation of the procedure is shown above (Figure 2). ESG does not involve any incision or scar in the abdomen, and recovery is quick. The procedure can be reversed when required and can also be repeated in the future, depending on the need.9


ESG is a safe procedure. The risk of adverse events reported with ESG is around 1-2%. The most frequent symptoms after ESG are abdominal pain and vomiting. The symptoms can be managed with medication and usually resolves within a few days.

Other uncommon adverse events include:

  • Post-procedural bleeding
  • Perforation (puncture through the wall of the stomach)
  • Entrapment of the adjacent organs

Most of these complications can be managed via the endoscope and rarely require surgery. Only extremely rarely may these complications be fatal.


ESG is a less invasive procedure than surgery for enabling patients with obesity to lose weight.10 By achieving the desired weight loss, patients lower their risk of obesity-related health problems like:

  • Type 2 diabetes mellitus
  • Hypertension
  • Heart disease and stroke
  • Fatty liver disease
  • High cholesterol
  • Sleep apnoea
  • Joint pain and osteoarthritis


Mrs ABC, a 42-year-old lady, visited our clinic seeking advice on the management of obesity. Her weight was 82 kg and she had a body mass index (BMI) of 31 kg/m2. She had diabetes mellitus on insulin, hypertension requiring two medications, and obstructive sleep apnoea. She started gaining weight after her second pregnancy six years ago. She had tried several measures to lose weight but had failed. She was afraid of bariatric surgery and not willing to go under the knife. She then underwent endoscopic sleeve gastroplasty and lost 18 kg at two years. Her life has since been transformed drastically.


The obese population in Singapore is increasing, and most of them are in the middle-age (30-50 years) group. To cater to their needs, the Department of Gastroenterology and Hepatology, Singapore General Hospital (SGH), has established a “Bariatric Endoscopy Service”, integrated with the SGH Obesity Centre. The bariatric endoscopy service is offered as integrated multidisciplinary care for patients with obesity. It offers a variety of minimally invasive procedures to meet patients’ needs and expectations.

Increased Acceptance
The service has adopted a patient-centric approach and fulfils the majority of treatment expectations, such as how ESG:

  • Is less risky
  • Is less invasive
  • Has a quick recovery
  • Is effective
  • Is reversible
  • Improves comorbidities and quality of life
  • Has no long-term side effects

Published Outcomes
More than 15,000 procedures have been performed worldwide, and more than 1,500 research articles have been
published on this topic.

The collaborative studies published by the SGH team show that:

  • At 2 years, the total body weight loss was 15-20%
  • The adverse event rate was 0.5%
  • The comorbid resolution was similar to bariatric surgery in the first year
  • The key to success is compliance with the multidisciplinary follow-up and lifestyle modification after the procedure


The treatment for obesity has expanded significantly, and there is now a variety of less invasive options to choose from. With these advancements and encouraging results, we hope to witness increasing physician and patient participation to offer and seek treatment and reduce the chronic disease burden.


  1. Khan SS, Ning H, Wilkins JT et al. Association of Body Mass Index With Lifetime Risk of Cardiovascular Disease and Compression of Morbidity. JAMA Cardiol. 2018 Apr 1; 3: 280-287
  2. Bhaskaran K, Dos-Santos-Silva I, Leon DA et al. Association of BMI with overall and cause-specific mortality: a population-based cohort study of 3・6 million adults in the UK. Lancet Diabetes Endocrinol. 2018 Dec; 6: 944-953
  3. Caterson ID, Alfadda AA, Auerbach P et al. Gaps to bridge: Misalignment between perception, reality and actions in obesity. Diabetes Obes Metab. 2019 Aug;21:1914-1924.
  4. Ryan DH, Yockey SR. Weight Loss and Improvement in Comorbidity: Differences at 5%, 10%, 15%, and Over. Curr Obes Rep. 2017;6(2):187-194. doi:10.1007/s13679-017-0262-y
  6. Ministry of Health Singapore: Government Health Expenditure.
  7. Asokkumar R, Babu MP, Bautista I, Lopez-Nava G. The Use of the OverStitch for Bariatric Weight Loss in Europe. Gastrointest Endosc Clin N Am. 2020 Jan;30(1):129-145.
  8. Lopeznava G, Asokkumar R, Bautista I, Laster J, Negi A, Fook Chong S, Nebreda Duran J, Espinet Coll E, Gebelli J, Garcia Ruiz A. Endoscopic Sleeve Gastroplasty (ESG), Laparoscopic Sleeve Gastrectomy (LSG), and Laparoscopic Greater Curve Plication (LGCP): Do They Differ at 2-years? Endoscopy. 2020 Jul 22.
  9. Lopez-Nava G, Asokkumar R. Step-by-step approach to endoscopic gastroplasty by a novel single-channel endoscopic suturing system. VideoGIE. 2019 Aug 8;4(10):444-446.
  10. Lopez-Nava G, Negi A, Bautista-Castano I, Rubio MA, Asokkumar R. Gut and Metabolic Hormones Changes After Endoscopic Sleeve Gastroplasty (ESG) Vs. Laparoscopic Sleeve Gastrectomy (LSG). Obes Surg. 2020 Jul;30(7):2642-2651.

Dr Ravishankar Asokkumar is a Consultant with the Department of Gastroenterology and Hepatology at Singapore General Hospital (SGH). He sub-specialises in Bariatric and Metabolic Endoscopy and Advanced Therapeutic Endoscopy. His expertise is in endoscopic gastroplasties and gastric volume reduction procedures.

In 2019, he did his HMDP Advanced Endoscopy fellowship in Spain with Professor Gontrand Lopez-Nava, MD, Ph.D., who is a renowned pioneer and key opinion leader in the field of bariatric endoscopy. During his fellowship, Dr Ravishankar was trained extensively in endoscopic gastroplasties, intragastric balloons, endoscopic bariatric surgery revision procedures, and novel therapies. He was involved in clinical research and has published
extensively on this topic.

GPs who would like more information about this procedure, please contact Dr Ravishankar at

GP Appointment Hotline: 6326 6060