Hypogonadotropic hypogonadism in obese women after biliopancreatic diversion

Benefits and Risks of Bariatric Surgery on Women's Reproductive Health: a Narrative Review

Bariatric surgery (BS) is escalating as the most efficient and endurable therapy for severe obesity. Women's reproductive health is essential to women's quality of life and is receiving increasing attention. However, despite the high prevalence of BS among women, the effect of BS on reproductive health remains underemphasis. The purpose of this narrative review is to provide an overview of BS on women's reproductive health, including their reproductive health before, during, and after pregnancy. Although limited attention has been given, current evidence highlights the substantial implications of bariatric surgery on reproductive health and reminds us of the importance of adopting decision-making conversations about reproductive health before bariatric surgery.

Effects of bariatric surgery on the menstruation- and reproductive-related hormones of women with obesity without polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

Bariatric surgery is an effective treatment for severe obesity. Several studies have been conducted on the effects of bariatric surgery on the reproductive function of women with obesity who do not have polycystic ovary syndrome (PCOS).

OBJECTIVES

To evaluate the effects of bariatric surgery on the menstruation and reproductive related hormones of women of childbearing age with who do not have PCOS.

SETTING

A systematic review and meta-analysis at a university hospital.

METHODS

Online databases were searched for all studies reporting the efficacy of bariatric surgery for women with obesity until March 2021. The language of publication was limited to English and Chinese. Incidence of abnormal menstruation and reproductive-related hormone levels were the primary outcomes.

RESULTS

Fifteen studies comprising 725 patients were enrolled in this meta-analysis. Results showed a significantly lower incidence of abnormal menstruation (relative risk: .40, 95% confidence interval [CI]: .20-.79, P = .008) after bariatric surgery. Moreover, bariatric surgery led to a decrease in serum insulin levels (mean difference [MD] = -13.12 mIU/L, 95% CI: -15.03 to -11.22, P < .00001), glucose (MD = -.91 mmol/L, 95% CI: -1.26 to -.56, P < .00001), triglyceride (MD = -.61 g/L, 95% CI: -.76 to -.46, P < .00001), total testosterone (MD = -.22 ng/mL, 95% CI: -.24 to -.20, P < .00001), dehydroepiandrosterone (DHEA) (MD = -25.34 μg/dL, 95% CI: -31.19 to -19.49, P < .00001), estradiol (MD = -25.13 pg/mL, 95% CI: -34.13 to -16.13, P < .00001), and anti-Mullerian hormone (AMH) (MD = -.40 ng/mL, 95% CI: -.67 to -.13, P = .003). Serum sex hormone binding globulin (SHBG) levels increased after bariatric surgery (MD = 43.99 nmol/L, 95% CI: 34.99-52.99, P < .00001).

CONCLUSION

Bariatric surgery can lower fasting insulin, glucose, and triglyceride levels, reduce the incidence of abnormal menstruation, decrease total serum testosterone, DHEA, estradiol, and AMH levels, and increase SHBG level for women with obesity of childbearing age who do not have PCOS. This meta-analysis indicated that bariatric surgery could be effective in improving reproductive function for women with severe obesity.

The effects of bariatric surgery on periconception maternal health: a systematic review and meta-analysis

BACKGROUND

Worldwide, the prevalence of obesity in women of reproductive age is increasing. Bariatric surgery is currently viewed as the most effective, long-term solution for this problem. Preconception bariatric surgery can reduce the prevalence of obesity-related subfertility and adverse maternal, pregnancy and birth outcomes. Maternal health during the periconception period is crucial for optimal gametogenesis and for embryonic and fetal development which also affects health in the later lives of both mother and offspring. Although preconception bariatric surgery improves several pregnancy outcomes, it can also increase the prevalence of pregnancy complications due to excessive and rapid weight loss. This can lead to iatrogenic malnutrition with vitamin deficiencies and derangements in metabolic and endocrine homeostasis. Thus, bariatric surgery can greatly influence periconception maternal health with consequences for reproduction, pregnancy and health in later life. However, its influence on periconception maternal health itself has never been reviewed systematically.

OBJECTIVE AND RATIONALE

The aim of this review was to investigate associations between bariatric surgery and determinants of periconception maternal health such as endocrine changes, fertility, vitamin status, irregular menstrual cycles, miscarriages and congenital malformations.

SEARCH METHODS

Medline, Embase, PubMed, Web of Science, Google Scholar and the Cochrane databases were used for the literature search until 1 November 2020. The search strategy terms included, among others, bariatric surgery, hormones, fertility, malformations, miscarriages and vitamin status. We searched for human studies that were written in English. Abstracts, reviews, meta-analyses and conference papers were excluded. The ErasmusAGE score was used to assess the quality of the included studies.

OUTCOMES

A total of 51 articles were analysed. The mean quality score was 5 (range 2-8). After bariatric surgery, hormonal axes normalized and menstrual cycle regularity was restored, resulting in increased fertility. Overall, there were no short-term risks for reproductive outcomes such as the increased risk of miscarriages or congenital malformations. However, the risk of vitamin deficiencies was generally increased after bariatric surgery. A meta-analysis of 20 studies showed a significant decrease in infertility (risk difference (RD) -0.24, 95% confidence interval (CI) -0.42, -0.05) and menstrual cycle irregularities (RD -0.24, 95% CI -0.34, -0.15) with no difference in rates of miscarriage (RD 0.00, 95% CI -0.09, 0.10) and congenital malformations (RD 0.01, 95% CI -0.02, 0.03).

WIDER IMPLICATIONS

The current systematic review and meta-analysis show associations between bariatric surgery and periconception maternal health and underlines the need for providing and personalizing preconception care for women after bariatric surgery. We recommend preconception care including the recommendation of postponing pregnancy until weight loss has stabilized, irrespective of the surgery-to-pregnancy interval, and until vitamin status is normalized. Therefore, regular monitoring of vitamin status and vitamin supplementation to restore deficiencies is recommended. Furthermore, this systematic review emphasizes the need for a long-term follow-up research of these women from the periconception period onwards as well as their pregnancies and offspring, to further improve care and outcomes of these mothers and children.

Effect of bariatric surgery on endogenous sex hormones and sex hormone-binding globulin levels: a systematic review and meta-analysis

BACKGROUND

Most studies have shown beneficial effect of bariatric surgery (BS) on serum levels of sex hormones.

OBJECTIVE

A systematic review and meta-analysis was conducted to examine the magnitude of possible changes in levels of sex hormones following BS.

SETTINGS

Electronic databases were searched, including PubMed, Scopus, Web of Science, and Embase, for relevant studies.

METHODS

The heterogeneity of the studies was examined by χ² tests and the degree of heterogeneity was estimated using I² statistic.

RESULTS

The results of pooled analyses revealed that BS caused a significant increase in luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) levels and conversely, decreased dehydroepiandrosterone (DHEA) and estradiol (E2) levels in males. For females, BS significantly increased LH, FSH, and SHBG levels and conversely, decreased androstenedione (AE), E2 and TT levels. Additionally, the level of progesterone (P), prolactin (PRL), free testosterone (FT) and dehydroepiandrosterone sulfate (DHEA-S) showed no significant changes in patients who had undergone BS.

CONCLUSION

BS changed most sex hormones levels including LH, FSH, TT, SHBG, AE, DHEA, and E2. It seems that BS is able to exert substantial impacts on sex hormones levels and as well as sexual function, however, larger, and more precise trials are required to specifically focus on these claims.

Low energy availability: history, definition and evidence of its endocrine, metabolic and physiological effects in prospective studies in females and males

Energy availability (EA) is defined as the amount of dietary energy available to sustain physiological function after subtracting the energetic cost of exercise. Insufficient EA due to increased exercise, reduced energy intake, or a combination of both, is a potent disruptor of the endocrine milieu. As such, EA is conceived as a key etiological factor underlying a plethora of physiological dysregulations described in the female athlete triad, its male counterpart and the Relative Energy Deficiency in Sport models. Originally developed upon female-specific physiological responses, this concept has recently been extended to males, where experimental evidence is limited. The majority of data for all these models are from cross-sectional or observational studies where hypothesized chronic low energy availability (LEA) is linked to physiological maladaptation. However, the body of evidence determining causal effects of LEA on endocrine, and physiological function through prospective studies manipulating EA is comparatively small, with interventions typically lasting ≤ 5 days. Extending laboratory-based findings to the field requires recognition of the strengths and limitations of current knowledge. To aid this, this review will: (1) provide a brief historical overview of the origin of the concept in mammalian ecology through its evolution of algebraic calculations used in humans today, (2) Outline key differences from the ‘energy balance’ concept, (3) summarise and critically evaluate the effects of LEA on tissues/systems for which we now have evidence, namely: hormonal milieu, reproductive system endocrinology, bone metabolism and skeletal muscle; and finally (4) provide perspectives and suggestions for research upon identified knowledge gaps.

The health pros and cons of continuous versus intermittent calorie restriction: more questions than answers

Beneficial effects on health of limiting food intake for certain periods of time have been recognized for a long time. While many diets can produce short-term weight loss, most fail to result in a long-lasting impact. Current data suggest that intermittent fasting may be beneficial for overall health and wellbeing. However, the lack of properly designed clinical studies makes it challenging to formulate evidence-based practice recommendations. Potential health risks of drastic changes in food intake are often ignored and might only be revealed after extensive follow-up. This review summarizes the popular intermittent dieting methods and their potential impact on fertility and reproduction.

Developing a model of nutritional amenorrhea in rhesus monkeys

Nutritional amenorrhea is defined as cessation of menstrual cycles resulting from a chronic negative energy balance. Although it is agreed that nutritional amenorrhea results from reduced secretion of GnRH, the neuroendocrine mechanisms leading to GnRH inhibition are poorly defined. Because the invasiveness of many neuroendocrine experimental approaches precludes its use in the clinical setting, we set out to establish a model of nutritional amenorrhea in rhesus monkeys. Studies were conducted in four normal-weight and one obese female rhesus monkey. Dietary intake was gradually reduced with the goal of achieving a 15-20% weight reduction. Dietary restriction inhibited ovulation in all animals. The weight loss required to inhibit ovulation ranged from 2-11% in the four normal-weight animals and was achieved with a 23% reduction in dietary intake. The time of initiating reduced food intake to first missed ovulation was 62 +/- 13 d. Greater weight loss (46% reduction) over a longer period (10 months) was required to inhibit ovulation in the obese monkey. The onset of anovulation was not preceded by changes in menstrual cycle length or progesterone secretion. Realimentation initiated ovulation at a weight that approximated the animal's weight at the time of the last ovulatory cycle during dietary restriction. By contrast, caloric intake at the return of ovulation during realimentation was 28% greater. This is the first demonstration that chronic dietary restriction can inhibit ovulation in rhesus monkeys. This model will be useful for studying the neuroendocrine mechanisms involved in diet-induced anovulation in primates.

The female athlete triad: an emerging role for physical therapy

Over the last thirty years, participation by girls and women in organized athletics has increased dramatically. This presents unique challenges in the area of sports medicine, orthopaedics, and pediatrics. While the benefits of participation in sports and exercise vastly outweigh the risks of permanent injury, an evolving concern is the number of stress fractures in active women. The female athlete triad ("triad") describes the coexistence of 3 distinct medical conditions that may occur in athletic girls and women. Originally, the triad included eating disorders, amenorrhea, and osteoporosis. Presently, it includes eating disorders/disordered eating behavior, amenorrhea/oligomenorrhea, and decreased bone mineral density (osteoporosis and osteopenia). Briefly, when coupled with inadequate nutrition, the high caloric expenditure of exercise training resultsin a sustained negative caloric balance or low energy availability, which is exquisitely sensed by the hypothalamus, initiating a complex neuroendocrine adaptive cascade. This cascade is associated with changes in the hypothalamic-pituitary-ovarian axis, such that estrogen levels are decreased, resulting in reproductive dysfunction that may include amenorrhea, oligomenorrhea, or anovulation. Low estrogen in otherwise young healthy women, like menopause, is associated with decreased bone mineral density and increased risk of fractures. The triad is not an inevitable consequence of participation in sports or physical activity at any level, however, exercise may contribute to the disruption of caloric balance. The triad is a complex disorder that requires intervention by a multidisciplinary team. Physical therapists bring a unique expertise to the team. The present review summarizes each component of the triad, component linkage, and the role of physical therapy in prevention, assessment, and intervention.

Energy availability, not body fatness, regulates reproductive function in women

The morbid consequences of menstrual disorders in athletes require medical diagnosis and treatment. Reproductive disruption appears to occur when energy availability (dietary energy intake minus exercise energy expenditure) falls below a threshold between 20 and 30 kcal x kgLBM(-1) x d(-1), and some women may be more severely affected than others by subthreshold energy availability.