Etonorgestrel concentrations in morbidly obese women following Roux-en-Y gastric bypass surgery: three case reports

The Effects of Bariatric Surgery on Pharmacokinetics of Drugs: a Review of Current Evidence

PURPOSE OF REVIEW

Obesity constitutes a major public health concern and has been recognized as an epidemic. To date, bariatric surgery remains the most effective way for substantial long-lasting weight loss in severe obesity. The purpose of this review is to summarize how the pharmacokinetics of drugs are affected by the most common types of bariatric surgery, i.e., Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

RECENT FINDINGS

Limited data are available regarding the changes in pharmacokinetics of drugs after bariatric surgery. The lack of existing guidelines may lead patients to experience drug toxicity or therapeutic undertreatment. Pharmacokinetic parameters that need to be taken into consideration postoperatively include gastric motility, gastric volume, pH, surface area, bile secretions, carrier proteins, and first-pass metabolism. For drugs with a narrow therapeutic index, other factors need to be monitored closely, including plasma drug levels, patients' clinical outcomes, and laboratory markers. Patients should be followed up frequently and treated in accordance with their response to the drug therapy. Bariatric surgery may affect the pharmacokinetics of various drugs, due to the resultant anatomical changes and the substantial weight loss. Therefore, there is a need to identify those potential changes and adjust patients' medication doses in order to achieve higher efficacy and avoid toxicity.

Best Practice Contraception Care for Women with Obesity: A Review of Current Evidence

The prevalence of obesity among females of reproductive age is increasing globally. Access to the complete range of appropriate contraceptive options is essential for upholding the reproductive rights of this population group. People with obesity can experience stigma and discrimination when seeking healthcare, and despite limited evidence for provider bias in the context of contraception, awareness for its potential at an individual provider and health systems level is essential. While use of some hormonal contraceptives may be restricted due to increased health risks in people with obesity, some methods provide noncontraceptive benefits including a reduced risk of endometrial cancer and a reduction in heavy menstrual bleeding which are more prevalent among individuals with obesity. In addition to examining systems-based approaches which facilitate the provision of inclusive contraceptive care, including long-acting reversible contraceptives which require procedural considerations, this article reviews current evidence on method-specific advantages and disadvantages for people with obesity to guide practice and policy.

Fertility, pregnancy and post partum management after bariatric surgery: a narrative review

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Of the women who gave birth in Australia in 2018, 47% had overweight or obesity, with obesity being associated with both maternal and fetal complications.

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Bariatric surgery improves fertility and some pregnancy‐related outcomes.

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Following bariatric surgery, pregnancy should be delayed by at least 12–18 months due to adverse pregnancy outcomes associated with rapid weight loss.

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Contraception should be prescribed after bariatric surgery, although the effectiveness of the oral contraceptive pill may be reduced due to malabsorption and contraceptive devices such as intrauterine devices should be considered as first line therapy.

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After bariatric surgery, women should undergo close monitoring for nutritional insufficiencies before, during and after pregnancy. Expert opinion recommends these women undergo dietary assessment and supplementation to prevent micronutrient deficiencies.

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Bariatric surgeons, bariatric medical practitioners, bariatric dieticians, the patient’s usual general practitioner, obstetricians, and maternity specialists should be involved to assist in the multidisciplinary management of these complex patients.

[Contraception in women with obesity]

Obese women are at high risk of unintended pregnancy. In addition, obesity is an important risk factor for venous thromboembolism events and arterial thrombosis. All of these data are to be considered in choosing a contraceptive method for obese women. The metabolic changes and the increased body mass of these women may be the cause of a reduction in the effectiveness of hormonal contraception. The progestin-only contraceptives (progestin only pills and etonogestrel subdermal implant) and the intra-uterine devices are the preferred contraceptive methods in women with obesity. The combined estrogen-progestin contraceptives may be proposed in young obese women without other cardiovascular risk factor. Obesity per se does not seem to increase the risk of failure of most contraceptive methods. Bariatric surgery is a complex situation. Contraception is needed for at least 12 months after surgery. Some bariatric surgery such as bypass can induce gastrointestinal malabsorption. In this situation, all oral contraceptives are not recommended because of a higher risk of failure.

Oral drug dosing following bariatric surgery: General concepts and specific dosing advice

Bariatric or weight‐loss surgery is a popular option for weight reduction. Depending on the surgical procedure, gastric changes like decreased transit time and volume and increased pH, decreased absorption surface in the small intestine, decreased exposure to bile acids and enterohepatic circulation, and decreased gastrointestinal transit time may be expected. In the years after bariatric surgery, patients will also substantially lose weight. As a result of these changes, the absorption, distribution, metabolism and/or elimination of drugs may be altered. The purpose of this article is to report the general influence of bariatric surgery on oral drug absorption, and to provide guidance for dosing of commonly used drugs in this special population. Upon oral drug administration, the time to maximum concentration is often earlier and this concentration may be higher with less consistent effects on trough concentrations and exposure. Additionally, prescription of liquid formulations to bariatric patients is supported by some reports, even though the high sugar load of these suspensions may be of concern. Studies on extended‐release medications result in an unaltered exposure for a substantial number of drugs. Also, studies evaluating the influence of timing after surgery show dynamic absorption profiles. Although for this group specific advice can be proposed for many drugs, we conclude that there is insufficient evidence for general advice for oral drug therapy after bariatric surgery, implying that a risk assessment on a case‐by‐case basis is required for each drug.

Pregnancy after bariatric surgery - a narrative literature review

The purpose of this review was to analyze the literature about pregnancy after bariatric surgery. We searched for available articles on the subject from the last decade (2010 to 2020). The positive impact of bariatric surgery on the level of comorbidities and pregnancy and neonatal outcomes cannot be overrated. Weight loss after bariatric surgery reduces the incidence of obesity-related conditions in pregnancy. A pregnancy in a woman after bariatric surgery should be considered a high-risk pregnancy and taken care of by a multidisciplinary team with appropriate micronutrient and vitamin supplementation provided. Optimum time to conception should be chosen following the international recommendations. Every woman after bariatric surgery should be aware of symptoms of surgical complications and immediately contact their surgeon in case of abdominal pain.

Clinical Practice Guidelines for Childbearing Female Candidates for Bariatric Surgery, Pregnancy, and Post-partum Management After Bariatric Surgery

Emerging evidence suggests that bariatric surgery improves pregnancy outcomes of women with obesity by reducing the rates of gestational diabetes, pregnancy-induced hypertension, and macrosomia. However, it is associated with an increased risk of a small-for-gestational-age fetus and prematurity. Based on the work of a multidisciplinary task force, we propose clinical practice recommendations for pregnancy management following bariatric surgery. They are derived from a comprehensive review of the literature, existing guidelines, and expert opinion covering the preferred type of surgery for women of childbearing age, timing between surgery and pregnancy, contraception, systematic nutritional support and management of nutritional deficiencies, screening and management of gestational diabetes, weight gain during pregnancy, gastric banding management, surgical emergencies, obstetrical management, and specific care in the postpartum period and for newborns.

Pregnancy after bariatric surgery: Consensus recommendations for periconception, antenatal and postnatal care

The objective of the study is to provide evidence-based guidance on nutritional management and optimal care for pregnancy after bariatric surgery. A consensus meeting of international and multidisciplinary experts was held to identify relevant research questions in relation to pregnancy after bariatric surgery. A systematic search of available literature was performed, and the ADAPTE protocol for guideline development followed. All available evidence was graded and further discussed during group meetings to formulate recommendations. Where evidence of sufficient quality was lacking, the group made consensus recommendations based on expert clinical experience. The main outcome measures are timing of pregnancy, contraceptive choice, nutritional advice and supplementation, clinical follow-up of pregnancy, and breastfeeding. We provide recommendations for periconception, antenatal, and postnatal care for women following surgery. These recommendations are summarized in a table and print-friendly format. Women of reproductive age with a history of bariatric surgery should receive specialized care regarding their reproductive health. Many recommendations are not supported by high-quality evidence and warrant further research. These areas are highlighted in the paper.

Contraceptive Care of Obese Women

Importance

In the United States, 27% of reproductive-aged women are overweight, and 35% are obese. Until recently, contraceptive research excluded women greater than 130% of their ideal body weight. Gaps in data limit evidence-based decision making for effective contraceptive counseling and management in this rapidly growing population.

Objectives

The aims of this summary are to review the benefits, adverse effects, and risk factors associated with contraceptive methods in obese women, with special attention to effectiveness, and provide contraceptive management and counseling recommendations for best clinical practice.

Evidence Acquisition

We performed a thorough search of PubMed for current literature, including original research articles, review articles, and guidelines on contraceptive counseling and management in obese women in the United States. We reviewed the body of evidence with special attention to studies published since recent Cochrane and systematic reviews on this topic.

Conclusions

Contraceptive use is safer than pregnancy, especially for obese women who have increased pregnancy risks. Baseline health is compromised by obesity, but contraceptive risks remain low. Long-acting, reversible contraceptive methods offer superior effectiveness, minimal risk, and numerous noncontraceptive benefits across body mass index groups. No substantial evidence supports ineffectiveness of any method in obese women except oral emergency contraception and the patch. Pharmacokinetic changes of obesity associated with other oral methods do not seem to result in clinically significant declines in effectiveness. Future contraceptive efficacy studies should include obese women to better discuss their contraceptive needs.

Relevance

This review is beneficial for all providers caring for reproductive-aged women wanting to avoid unintended pregnancy.

Oral Contraceptives after Bariatric Surgery

OBJECTIVE

Bariatric surgery offers a highly effective mode of treatment for obese patients. Some procedures such as bypass cause an alteration in normal gastrointestinal tract with possible consequences for the uptake of orally administered drugs.

METHODS

We assessed the literature to ascertain whether the use of oral drugs and especially oral contraceptives is effective and adequate after bariatric surgery.

RESULTS

The bioavailability of drugs could be affected by the solubility and pH of the modified medium after bariatric surgery and by the loss of gastrointestinal transporters. Bariatric surgery could potentially result in a transient change in the absorption of drugs such as analgesics, antibiotics, antiarrhythmics, anticoagulants, psychotropic, and oral contraceptive drugs. Effective contraception is especially critical in the postoperative period, and implants might be representing a safe contraceptive method in women undergoing bariatric surgery.

CONCLUSION

Each drug will have to be evaluated with respect to its site of absorption and its mechanism of absorption, with special attention on parameters influencing the effectiveness of the absorption processes.

Practical Recommendations of the Obesity Management Task Force of the European Association for the Study of Obesity for the Post-Bariatric Surgery Medical Management

Bariatric surgery is today the most effective long-term therapy for the management of patients with severe obesity, and its use is recommended by the relevant guidelines of the management of obesity in adults. Bariatric surgery is in general safe and effective, but it can cause new clinical problems and is associated with specific diagnostic, preventive and therapeutic needs. For clinicians, the acquisition of special knowledge and skills is required in order to deliver appropriate and effective care to the post-bariatric patient. In the present recommendations, the basic notions needed to provide first-level adequate medical care to post-bariatric patients are summarised. Basic information about nutrition, management of co-morbidities, pregnancy, psychological issues as well as weight regain prevention and management is derived from current evidences and existing guidelines. A short list of clinical practical recommendations is included for each item. It remains clear that referral to a bariatric multidisciplinary centre, preferably the one performing the original procedure, should be considered in case of more complex clinical situations.

[Safety profile of etonogestrel contraceptive implant (Nexplanon® and Implanon®) reported in France]

OBJECTIVES

The aim of the study was to assess the incidence of adverse effects (AE) reported with etonogestrel contraceptive implant in France (Implanon^® and Nexplanon^®).

MATERIALS AND METHODS

All cases of AE or unintended pregnancies reported to health authorities or to the firm were analyzed.

RESULTS

During 10 years, 5433 AE and 789 unintended pregnancies were reported. Only 388 (7 %) were serious. There were 1137 reports of difficulties to remove, failure to locate or migration, 430 of insertion difficulties and 203 of deformation or expulsion of the implant. Among other AE, the most common were 1694 gynecological AE, 524 skin reactions and 437 metabolic AE. Since the marketing of Nexplanon^® which causes less deep insertions, the incidence of migrations, removal or insertion difficulties has decreased overall (0.92 vs. 1.31/1000 patients), particularly the incidence of removal difficulties, location failures or migrations (0.12 vs 1.01/1000). The infrequent but serious AE were infectious complications at the implant site and pregnancies. When the circumstances of the pregnancy were known, the contraceptive failure was due to the apparent inefficiency of the implant (n=224), to a technique failure (n=203) or to a drug-drug interaction (n=59).

CONCLUSION

This study confirms that AE of this implant are frequent but not serious, except for the pregnancies. The incidence of complications related to insertion decreased with Nexplanon^®. Among other preventable AE, unintended pregnancies due to a drug-drug interaction would require to be better known by the practitioner.

Relationship between etonogestrel level and BMI in women using the contraceptive implant for more than 1 year

Progestin-only contraceptive methods, including the 3-year, single-rod etonogestrel (ENG) implant, may be preferred for obese women to avoid additional estrogen-related thrombosis risk; however, whether obese women receive an ENG sufficient dose to suppress ovulation is understudied. Our analysis expands on the limited information currently available by studying ENG levels related to body mass index (BMI) in a community sample of primarily Hispanic women. This cross-sectional, descriptive study of 52 long-term implant users found comparable ENG levels across a wide BMI range (p=.1). These results further support that ENG levels are independent of BMI through 3 years of implant use and are thus reassuring that ENG implants will be effective for women of all BMIs.

[Pregnancy and bariatric surgery: Critical points]

More than 200,000 people underwent obesity surgery in France. Most of them are women. Pregnancy after bariatric surgery is becoming a common situation. This surgery results in major nutritional and gastro-intestinal tract modifications that may influence or be influenced by pregnancy, and yields benefits as well as complications. A multidisciplinary management including a nutritionist, an obstetrician, an anesthesiologist, and a bariatric surgeon is required. The aim of this review is to analyze the impact of bariatric surgery on pregnancy and vice versa, and to identify the key points of this management.

Obesity and contraception

Utilizing contraception is critical in preventing unintended pregnancies among obese women. However, clinicians and obese patients may be unclear about which contraceptive methods are optimal. This review discusses the literature on any weight gain associated with contraceptive use, contraceptive efficacy among obese women, and special considerations for contraceptive method selection for women after bariatric surgery. The review also covers new findings on oral emergency contraception and obesity.

Obesity and hormonal contraceptive efficacy

Obesity is a major public health concern affecting an increasing proportion of reproductive-aged women. Avoiding unintended pregnancy is of major importance, given the increased risks associated with pregnancy, but obesity may affect the efficacy of hormonal contraceptives by altering how these drugs are absorbed, distributed, metabolized or eliminated. Limited data suggest that long-acting, reversible contraceptives maintain excellent efficacy in obese women. Some studies demonstrating altered pharmacokinetic parameters and increased failure rates with combined oral contraceptives, the contraceptive patch and emergency contraceptive pills suggest decreased efficacy of these methods. It is unclear whether bariatric surgery affects hormonal contraceptive efficacy. Obese women should be offered the full range of contraceptive options, with counseling that balances the risks and benefits of each method, including the risk of unintended pregnancy.

Pharmacokinetics of the etonogestrel contraceptive implant in obese women

OBJECTIVE

We sought to examine the pharmacokinetics and acceptability of the etonogestrel contraceptive implant in obese women.

STUDY DESIGN

We developed and validated a plasma etonogestrel concentration assay and enrolled 13 obese (body mass index ≥30) women and 4 normal-weight (body mass index <25) women, who ensured comparability with historical controls. Etonogestrel concentrations were measured at 50-hour intervals through 300 hours postinsertion, then at 3 and 6 months to establish a pharmacokinetic curve.

RESULTS

All obese participants were African American, while all normal-weight participants were white. Across time, the plasma etonogestrel concentrations in obese women were lower than published values for normal-weight women and 31-63% lower than in the normal-weight study cohort, although these differences were not statistically significant. The implant device was found highly acceptable among obese women.

CONCLUSION

Obese women have lower plasma etonogestrel concentration than normal-weight women in the first 6 months after implant insertion. These findings should not be interpreted as decreased contraceptive effectiveness without additional considerations.