Surgically induced interpregnancy weight loss and prevalence of overweight and obesity in offspring

Impact of maternal bariatric surgery on offspring perinatal cardiac function: A prospective study

OBJECTIVE

To assess perinatal cardiac function in offspring of women with previous bariatric surgery and examine its association with maternal glucose control.

DESIGN

Prospective study.

SETTING

Maternity unit, UK.

POPULATION

Fifty-four fetuses/neonates; 29 of post-bariatric surgery women and 25 of women without surgery.

METHODS

Prospective, longitudinal observational study of pregnant women with and without previous bariatric surgery, matched for early pregnancy body mass index. Cardiac function of all offspring was assessed by two-dimensional conventional, spectral tissue Doppler and speckle-tracking echocardiography at 35-37 weeks of gestation and at 5-7 weeks of age. Maternal glycated haemoglobin (HbA1c) was measured at 27-30 weeks of gestation. Maternal demographics and fetal/infant cardiac function indices were compared between the groups. Correlation coefficient (r) is reported.

MAIN OUTCOME MEASURES

Fetal/infant cardiac function indices.

RESULTS

Compared with no-bariatric neonates, offspring of post-bariatric women were smaller at birth (birthweight centiles: 64.96 ± 36.41 versus 40.17 ± 27.99; p = 0.007). There were no significant differences in fetal/infant cardiac function indices and perinatal cardiac changes, between groups. There was a positive correlation between maternal HbA1c and fetal left ventricular (LV) longitudinal strain (r = 0.33) and LV longitudinal strain rate (r = 0.29), suggesting an inverse relation between HbA1c and fetal LV systolic function, but this was mainly seen in offspring of women with no previous bariatric surgery (r = 0.56 and r = 0.50, respectively).

CONCLUSIONS

Maternal bariatric surgery does not appear to inadvertently affect the offspring cardiac performance. We found an inverse correlation between maternal HbA1c levels and fetal LV systolic function but this was mainly seen in the no-bariatric pregnancies.

Endocan: A biomarker for endothelial dysfunction and inflammation, linking maternal obesity and pediatric obesity in a cohort of preterm neonates

OBJECTIVES

Numerous animal and epidemiologic studies have demonstrated a positive association between maternal obesity in pregnancy and obesity in offspring. The biologic mechanisms of this association remain under investigation. One proposed mechanism includes fetoplacental endothelial dysfunction secondary to inflammation. Endocan is a relatively new biomarker for endothelial dysfunction and inflammation. Our objectives were to examine (1) the association between maternal obesity and neonatal serum endocan at birth, and (2) the association between neonatal serum endocan at birth and pediatric obesity at 24-36 months of age.

STUDY DESIGN

This was a secondary analysis of a prospective cohort of neonates born < 33 weeks gestation. Serum endocan was collected within 48 hours of birth. Serum endocan levels were compared in neonates born to obese mothers vs. those born to non-obese mothers. BMI data were retrospectively collected from cohort neonates between 24 and 36 months of age.

RESULTS

The analysis included 120 mother/neonate dyads. Neonates born to obese mothers had higher median serum endocan at birth compared to neonates born to non-obese mothers (299 ng/L [205-586] vs. 251 ng/L [164-339], p = 0.045). In a linear regression modeled on neonatal serum endocan level, maternal obesity had a statistically significant positive association (p = 0.021). Higher mean serum endocan level at birth was associated with pediatric obesity between 24 and 36 months (obese vs. non-obese offspring; 574 ng/L (222) vs. 321 ng/L (166), p = 0.005).

CONCLUSIONS

In our cohort of preterm neonates, elevated serum endocan at birth was associated with both maternal obesity and downstream pediatric obesity. More research is needed to understand intergenerational transmission of obesity. A large focus has been on epigenetic modification. Endothelial dysfunction and inflammation may play important roles in these pathways. Effective biomarkers, including endocan, may also serve as intermediate outcomes in future pregnancy research.

The impact of maternal bariatric surgery on long-term health of offspring: a scoping review

While pregnancy post-bariatric surgery has become increasingly common, little is known about whether and how maternal bariatric surgery affects the next generation. This scoping review aimed to collate available evidence about the long-term health of offspring following maternal bariatric surgery. A literature search was conducted using three databases (PubMed, PsycINFO, EMBASE) to obtain relevant human and animal studies. A total of 26 studies were included: 17 were ancillary reports from five "primary" studies (three human, two animal studies) and the remaining nine were "independent" studies (eight human, one animal studies). The human studies adopted sibling-comparison, case-control, and single-group descriptive designs. Despite limited data and inconsistent results across studies, findings suggested that maternal bariatric surgery appeared to (1) modify epigenetics (especially genes involved in immune, glucose, and obesity regulation); (2) alter weight status (unclear direction of alteration); (3) impair cardiometabolic, immune, inflammatory, and appetite regulation markers (primarily based on animal studies); and (4) not affect the neurodevelopment in offspring. In conclusion, this review supports that maternal bariatric surgery has an effect on the health of offspring. However, the scarcity of studies and heterogenous findings highlight that more research is required to determine the scope and degree of such effects. IMPACT: There is evidence that bariatric surgery modifies epigenetics in offspring, especially genes involved in immune, glucose, and obesity regulation. Bariatric surgery appears to alter weight status in offspring, although the direction of alteration is unclear. There is preliminary evidence that bariatric surgery impairs offspring's cardiometabolic, immune, inflammatory, and appetite regulation markers. Therefore, extra care may be needed to ensure optimal growth in children born to mothers with previous bariatric surgery.

Bariatric surgery and reproduction-implications for gynecology and obstetrics

As the rates of obesity continue to rise across the world, there has been an increasing resort to bariatric surgery amongst the options for treatment. Through the reproductive lifespan, between menarche and menopause, women might benefit from this surgical intervention, which may have a bearing on other aspects of their health. The consequences of bariatric surgery have been reported and evaluated from various perspectives in obstetrics and gynecology. Fertility and sexuality are enhanced, but not all gynecological diseases are ameliorated. There are also psychological and behavioral sequelae to be cognizant of. With multi-disciplinary and responsive care, most post-bariatric pregnancies have satisfactory outcomes. The effects of bariatric surgery on the babies conceived thereafter remains a subject of interest, whereas the possible effect on the climacteric is speculative.

Maternal Bariatric Surgery and Offspring Health: A Sibling Matched Analysis Comparing Offspring Born before and after the Surgery

(1) Background: Due to the global escalation in the prevalence of obesity, bariatric surgeries have become a popular solution in many western countries. The aim of the current study was to compare offspring health and the obesity of women before and after undergoing bariatric surgeries. (2) Methods: A retrospective population-based study was performed, including all singleton deliveries which occurred at a tertiary medical center between the years 1991-2021. Among women who had bariatric surgeries, the health of the offspring born before and after the surgery were compared. The offspring were followed up until the age of 18 years, and their hospitalization records were summarized. The incidence of hospitalization with either endocrine, cardiac, respiratory, neurologic, or infectious diagnoses were compared between the groups, as well as offspring obesity. Multivariable Cox proportional models were used to match between siblings and to address confounding variables, including maternal age, gestational age at delivery, fertility treatment, smoking and pregnancy hypertensive disorders. (3) Results: The study population included 3074 deliveries of women who underwent bariatric surgeries (1586 were before and 1488 after the surgery). Offspring born after maternal bariatric surgeries were at a comparable risk for most morbidities, besides endocrine-related morbidities (3.1% vs. 5.0%, OR = 1.61; 1.1-2.35) and obesity (2.5% vs. 4.1%, OR = 1.63; 1.08-2.48). The risk for these morbidities was higher among the offspring of mothers after, vs. before, the surgery, despite adjustment for maternal age and other confounding variables. (4) Conclusions: While bariatric surgeries are considered an effective treatment for obesity, it seems to have less of an effect on the offspring of women who underwent such surgeries. Other persistent factors are most likely associated with the offspring's risk for morbidities, especially endocrine morbidities and obesity, which remain even though the mother underwent bariatric surgeries.

The Legacy of Parental Obesity: Mechanisms of Non-Genetic Transmission and Reversibility

While a dramatic increase in obesity and related comorbidities is being witnessed, the underlying mechanisms of their spread remain unresolved. Epigenetic and other non-genetic mechanisms tend to be prominent candidates involved in the establishment and transmission of obesity and associated metabolic disorders to offspring. Here, we review recent findings addressing those candidates, in the context of maternal and paternal influences, and discuss the effectiveness of preventive measures.

Maternal antagonism of Glp1 reverses the adverse outcomes of sleeve gastrectomy on mouse offspring

Mothers that underwent bariatric surgery are at higher risk for delivering a small-for-gestational age (SGA) infant. This phenomenon is attributed to malabsorption and rapid weight loss following surgery. We compared pregnancy outcomes in lean mice that underwent sham surgery or sleeve gastrectomy (SG). SG led to a reduction in glucose levels and an increase in postprandial levels of glucagon-like peptide 1 (Glp1) without affecting mice weight during pregnancy. Pups of SG-operated mice (SG pups) were born SGA. The placenta and pancreas of the pups were not affected by SG, although a high-fat diet caused hepatic steatosis and glucose intolerance in male SG pups. Treatment with a Glp1 receptor antagonist during pregnancy normalized the birth weight of SG pups and diminished the adverse response to a high-fat diet without affecting glucose levels of pregnant mice. The antagonist did not affect the birth weight of pups of sham-operated mice. Our findings link elevated Glp1 signaling, rather than weight loss, to the increased prevalence of SGA births following bariatric surgery with metabolic consequences for the offspring. The long-term effects of bariatric surgery on the metabolic health of offspring of patients require further investigation.

Exploring the causal effect of maternal pregnancy adiposity on offspring adiposity: Mendelian randomisation using polygenic risk scores

BACKGROUND

Greater maternal adiposity before or during pregnancy is associated with greater offspring adiposity throughout childhood, but the extent to which this is due to causal intrauterine or periconceptional mechanisms remains unclear. Here, we use Mendelian randomisation (MR) with polygenic risk scores (PRS) to investigate whether associations between maternal pre-/early pregnancy body mass index (BMI) and offspring adiposity from birth to adolescence are causal.

METHODS

We undertook confounder adjusted multivariable (MV) regression and MR using mother-offspring pairs from two UK cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC) and Born in Bradford (BiB). In ALSPAC and BiB, the outcomes were birthweight (BW; N = 9339) and BMI at age 1 and 4 years (N = 8659 to 7575). In ALSPAC only we investigated BMI at 10 and 15 years (N = 4476 to 4112) and dual-energy X-ray absorptiometry (DXA) determined fat mass index (FMI) from age 10-18 years (N = 2659 to 3855). We compared MR results from several PRS, calculated from maternal non-transmitted alleles at between 29 and 80,939 single nucleotide polymorphisms (SNPs).

RESULTS

MV and MR consistently showed a positive association between maternal BMI and BW, supporting a moderate causal effect. For adiposity at most older ages, although MV estimates indicated a strong positive association, MR estimates did not support a causal effect. For the PRS with few SNPs, MR estimates were statistically consistent with the null, but had wide confidence intervals so were often also statistically consistent with the MV estimates. In contrast, the largest PRS yielded MR estimates with narrower confidence intervals, providing strong evidence that the true causal effect on adolescent adiposity is smaller than the MV estimates (Pdifference = 0.001 for 15-year BMI). This suggests that the MV estimates are affected by residual confounding, therefore do not provide an accurate indication of the causal effect size.

CONCLUSIONS

Our results suggest that higher maternal pre-/early-pregnancy BMI is not a key driver of higher adiposity in the next generation. Thus, they support interventions that target the whole population for reducing overweight and obesity, rather than a specific focus on women of reproductive age.

Instrumental variable analysis using offspring BMI in childhood as an indicator of parental BMI in relation to mortality

Childhood BMI shows associations with adult mortality, but these may be influenced by effects of ill health in childhood on BMI and later mortality. To avoid this, we used offspring childhood BMI as an instrumental variable (IV) for own BMI in relation to mortality and compared it with conventional associations of own childhood BMI and own mortality. We included 36,097 parent-offspring pairs with measured heights and weights from the Copenhagen School Health Records Register and register-based information on death. Hazard ratios (HR) were estimated using adjusted Cox regression models. For all-cause mortality, per zBMI at age 7 the conventional HR = 1.07 (95%CI: 1.04-1.09) in women and 1.02 (95%CI: 0.92-1.14) in men, whereas the IV HR = 1.23 (95%CI: 1.15-1.32) in women and 1.05 (95%CI: 0.94-1.17) in men. Per zBMI at age 13, the conventional HR = 1.11 (95%CI: 1.08-1.15) in women and 1.03 (95%CI: 0.99-1.06) in men, whereas the IV HR = 1.30 (95%CI: 1.19-1.42) in women and 1.15 (95%CI: 1.04-1.29) in men. Only conventional models showed indications of J-shaped associations. Our IV analyses suggest that there is a causal relationship between BMI and mortality that is positive at both high and low BMI values.

Maternal obesity and metabolic disorders associate with congenital heart defects in the offspring: A systematic review

BACKGROUND

Congenital heart defects (CHDs) are the most common congenital malformations. The aetiology of CHDs is complex. Large cohort studies and systematic reviews and meta-analyses based on these have reported an association between higher risk of CHDs in the offspring and individual maternal metabolic disorders such as obesity, diabetes, hypertension, and preeclampsia, all conditions that can be related to insulin resistance or hyperglycaemia. However, the clinical reality is that these conditions often occur simultaneously. The aim of this review is, in consequence, both to evaluate the existing evidence on the association between maternal metabolic disorders, defined as obesity, diabetes, hypertension, preeclampsia, dyslipidaemia and CHDs in the offspring, as well as the significance of combinations, such as metabolic syndrome, as risk factors.

METHODS

A systematic literature search of papers published between January 1, 1990 and January 14, 2021 was conducted using PubMed and Embase. Studies were eligible if they were published in English and were case-control or cohort studies. The exposures of interest were maternal overweight or obesity, hypertension, preeclampsia, diabetes, dyslipidaemia, and/or metabolic syndrome, and the outcome of interest was CHDs in the offspring. Furthermore, the studies were included according to a quality assessment score.

RESULTS

Of the 2,250 identified studies, 32 qualified for inclusion. All but one study investigated only the individual metabolic disorders. Some disorders (obesity, gestational diabetes, and hypertension) increased risk of CHDs marginally whereas pre-gestational diabetes and early-onset preeclampsia were strongly associated with CHDs, without consistent differences between CHD subtypes. A single study suggested a possible additive effect of maternal obesity and gestational diabetes.

CONCLUSIONS

Future studies of the role of aberrations of the glucose-insulin homeostasis in the common aetiology and mechanisms of metabolic disorders, present during pregnancy, and their association, both as single conditions and-particularly-in combination, with CHDs are needed.

Adiposity, psychomotor and behaviour outcomes of children born after maternal bariatric surgery

BACKGROUND

Bariatric surgery before pregnancy can result in improved maternal fertility. However, long-term data on the consequences at childhood age are currently lacking.

METHODS

EFFECTOR is a prospective cohort study of children (aged 4 to 11 years) born to mothers who underwent bariatric surgery (BS) before pregnancy (n = 36), controls with overweight/obesity (OW/OB) matched on pre-pregnancy BMI (n = 36) and normal weight controls (NL) (n = 35). We performed prospective collection of anthropometric data, data on psychomotor development, school functioning and behaviour (Strengths and Difficulties Questionnaire (SDQ), Child Behaviour Checklist (CBCL)).

RESULTS

The children born after bariatric surgery (BS) presented with the highest body-weight SDS (0.70 vs 0.14 in OW/OB and -0.09 in NL; P = .006) and BMI SDS (0.47 vs -0.02 in OW/OB and -0.42 in NL; P = .01). A higher excess in body fat percentage and waist circumference SDS were found in the BS group (5.7 vs 1.4 in OW/OB and -0.1 in NL; P < .001 and 0.61 vs 0.16 in OW/OB and -0.15 in NL; P = .04). The SDQ questionnaires revealed a higher amount of overall problems in the BS offspring (11.1 vs 7.5 in OW/OB and 8.1 in NL; P = .03), with a higher externalizing score at the CBCL (52.0 vs 44.2 in OW/OB and 47.0 in NL; P = .03).

CONCLUSION

Maternal bariatric surgery does not appear to protect the offspring for childhood overweight and obesity. Parents reported more behaviour problems in these children, especially externally of nature.

Postnatal Health in Children Born to Women After Bariatric Surgery

INTRODUCTION

The aim of this study is to evaluate short- and long-term consequences in children born to women after different bariatric surgery (BS) procedures.

METHODS

A questionnaire survey was given to the mothers referred from 1994 to 2019 to our center for pregnancy and delivery management after BS procedures: (a) malabsorptive surgery, (b) restrictive procedures, and (c) combined restrictive-malabsorptive procedures.

RESULTS

Data from 74 children born after BS, aged 0 month to 12 years, were analyzed. The prevalence of children with underweight was 5.4%, normal weight 59.5%, overweight 16.2%, and obesity 18.9%. The prevalence of obesity was higher in children pre-school aged than that in school-aged ones. Neurodevelopmental disorders were more frequent if maternal BMI before bariatric surgery was ≥ 41 kg/m² (p = 0.008), as well as if the pregnancy occurred less than 18 months after BS (p = 0.028). In school-aged children conceived within 18 months after BS, the highest risk of neurodevelopmental disorders (p = 0.028) and overweight (p = 0.018) was observed. The prevalence of neurodevelopmental disorders was much higher for small for gestational age babies (p = 0.048). Children born after biliopancreatic diversion (BPD) showed less maternal breastfeeding, shorter breastfeeding duration, more overweight, and more occurrence of atopic dermatitis in comparison with children born after other bariatric procedures.

CONCLUSIONS

Postnatal health in children born to women after BS was impaired by long-term consequences and by other diseases later in life. Children born after BPD were particularly at higher risk for short and long term consequences when compared to children born after other BS procedures.

Dysregulated appetitive leptin signaling in male rodent offspring from post-bariatric dams

Bariatric surgery produces significant positive benefits to recipients such as resolution of various obesity-related comorbidities, including improved reproductive function. Females of childbearing age seek bariatric surgical remedies to improve their chance of successful pregnancy; however, limited knowledge exists on the impact of surgical weight loss to subsequently born offspring.

We previously reported that circulating leptin levels were reduced in pregnant females having previously received vertical sleeve gastrectomy (VSG) in comparison to control dams having received Sham surgery. Furthermore, the levels of leptin receptors in the VSG placenta were also reduced in comparison to controls in. These data suggest there may be a significant difference in leptin signaling during pregnancy that may produce an altered developmental environment for the offspring.

Here, we investigate the adult offspring of dams having received VSG or Sham-VSG prior to pregnancy. Endogenous fasting plasma leptin levels were not different between Sham and VSG offspring. Fasting leptin receptor mRNA in the medial basal hypothalamus (MBH) was elevated in VSG offspring in comparison to Sham. Intraperitoneal administration of exogenous leptin produced reductions in acute food intake in male Sham offspring, but did not reduce food intake at any time point measured in male VSG offspring. Using Western blot, we identified elevated pSTAT3 and pSTAT3/STAT3 ratios in the MBH of post-VSG offspring in comparison to controls. Using immunohistochemistry, we found an increased number of pSTAT positive cells in the arcuate nucleus in the Sham offspring in comparison to VSG. In contrast, within the paraventricular and ventromedial hypothalamic nuclei the VSG offspring had elevated numbers of pSTAT-positive cells in comparison to controls. Collectively, these data support our hypothesis that leptin signaling is dysregulated in VSG offspring and may be partially responsible for the long-term impact of maternal bariatric surgery on the metabolic health of offspring.

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Pregnancies following bariatric surgeries have reduced circulating leptin and increased leptin receptors in placenta.

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Offspring of dams having previously received bariatric surgery have altered growth trajectories during postnatal life.

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The male offspring experience have elevated expression of hypothalamic leptin receptors.

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The bariatric offspring are non-responsive to the anorexigenic effects of exogenous leptin administration.

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pSTAT in the hypothalamus of post-bariatric offspring is elevated without a change in food intake.

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Leptin signaling may be responsible for long-term metabolic changes in post-bariatric offspring.

Change in modifiable maternal characteristics and behaviours between consecutive pregnancies and offspring adiposity: A systematic review

Causal evidence links modifiable maternal exposures during the periconceptional period with offspring obesity. The interconception period may be an important time to intervene. We systematically identified studies examining change in modifiable maternal exposures between pregnancies and offspring adiposity. We searched for longitudinal studies published between 1990 and 2019, which included measurements taken on at least two occasions in the period from 1 year prior to the conception of the first birth to the time of the second birth, and which included a measure of adiposity in second, or higher order, siblings. Age, ethnicity and genetics were not considered modifiable; all other factors including length of the interpregnancy interval were. Eleven studies satisfied the inclusion criteria. Higher interpregnancy weight gain or loss, maternal smoking inception, mothers smoking in their first pregnancy and quitting, increasing the number of cigarettes smoked and longer interpregnancy intervals were positively associated with adiposity in second or higher order children. Vaginal birth after caesarean delivery was protective. Further research is needed to ascertain whether the risk of adiposity is fixed based on first pregnancy exposures or if interpregnancy change alters the risk for a subsequent child. This can inform the type and effectiveness of interventions for mothers prior to a subsequent pregnancy.

Curbing Obesity from One Generation to Another: the Effects of Bariatric Surgery on the In Utero Environment and Beyond

Approximately 250,000 individuals seek bariatric surgery each year in the USA for the long-term resolution of obesity-related comorbidities. Greater than 80% of these individuals are women and approximately half are of child-bearing age. Although there are many positive metabolic benefits that are realized through surgical weight loss for both men and women, the various long-term hormonal, molecular, nutrient, and epigenetic changes following bariatric surgery have not been evaluated for the surgical recipient or in the context of pregnancy and the offspring. Pregnancy may be a vulnerable period of time for the bariatric surgery recipient, and thoughtful consideration of pregnancy management should be taken by health care providers and recipients alike. The purpose of this review is to explore potential etiologies of some of the gestation-specific outcomes for the mother and offspring.

Maternal weight change between successive pregnancies: an opportunity for lifecourse obesity prevention

Maternal obesity is a major risk factor for adverse health outcomes for both the mother and the child, including the serious public health problem of childhood obesity which is globally on the rise. Given the relatively intensive contact with health/care professionals following birth, the interpregnancy period provides a golden opportunity to focus on preconception and family health, and to introduce interventions that support mothers to achieve or maintain a healthy weight in preparation for their next pregnancy. In this review, we summarise the evidence on the association between interpregnancy weight gain with birth and obesity outcomes in the offspring. Gaining weight between pregnancies is associated with an increased risk of large-for-gestational age (LGA) birth, a predictor of childhood obesity, and weight loss between pregnancies in women with overweight or obesity seems protective against recurrent LGA. Interpregnancy weight loss seems to be negatively associated with birthweight. There is some suggestion that interpregnancy weight change may be associated with preterm birth, but the mechanisms are unclear and the direction depends if it is spontaneous or indicated. There is limited evidence on the direct positive link between maternal interpregnancy weight gain with gestational diabetes, pre-eclampsia, gestational hypertension and obesity or overweight in childhood, with no studies using adult offspring adiposity outcomes. Improving preconception health and optimising weight before pregnancy could contribute to tackling the rise in childhood obesity. Research testing the feasibility, acceptability and effectiveness of interventions to optimise maternal weight and health during this period is needed, particularly in high-risk and disadvantaged groups.

Maternal, neonatal insulin resistance and neonatal anthropometrics in pregnancies following bariatric surgery

OBJECTIVE

An increasing number of women present pregnant having undergone bariatric surgery, a popular treatment for sustainable weight loss. The aim of the study was to investigate the effect, if any, of bariatric surgery on maternal and neonatal insulin resistance (IR) and neonatal body fat composition.

METHODS

Maternal IR, at 28 weeks of gestation during 2-hour 75 g oral glucose tolerance test (OGTT), neonatal IR, from umbilical cord venous blood, and neonatal birthweight and body fat composition (calculated by measuring skin folds) at birth were evaluated in 41 post-bariatric and 82 pregnant women with similar early pregnancy body mass index but no history of such surgery. Insulin resistance was assessed using the homeostasis model assessment of IR (HOMA-IR).

RESULTS

In the post-bariatric surgery group, compared to the no surgery group, maternal HOMA-IR (1.15 [1.04-2.07] vs 2.20 [1.53-3.38]; p < 0.01), neonatal birthweight (p < 0.01) and body fat (p < 0.01) were significantly lower whereas neonatal cord HOMA-IR was similar (1.29 [0.65-2.39] vs 1.19 [0.46-1.93]; p = 0.49). In the no surgery group, there was a positive correlation between maternal and neonatal HOMA-IR (p = 0.03) and between neonatal HOMA-IR and body fat (p < 0.01). However, no such significant correlations were detected in the post-bariatric surgery group.

CONCLUSION

Pregnancy following bariatric surgery is associated with a reduction in maternal IR and altered neonatal body composition with significantly lower birthweight and adiposity but no improvement in cord IR.

Management of Pregnant Women after Bariatric Surgery

The prevalence of obesity is growing worldwide, and strategies to overcome this epidemic need to be developed urgently. Bariatric surgery is a very effective treatment option to reduce excess weight and often performed in women of reproductive age. Weight loss influences fertility positively and can resolve hormonal imbalance. So far, guidelines suggest conceiving after losing maximum weight and thus recommend conception at least 12-24 months after surgery. As limited data of these suggestions exist, further evidence is urgently needed as well for weight gain in pregnancy. Oral glucose tolerance tests for the diagnosis of gestational diabetes mellitus (GDM) should not be performed after bariatric procedures due to potential hypoglycaemic adverse events and high variability of glucose levels after glucose load. This challenges the utility of the usual diagnostic criteria for GDM in accurate prediction of complications. Furthermore, recommendations on essential nutrient supplementation in pregnancy and lactation in women after bariatric surgery are scarce. In addition, nutritional deficiencies or daily intake recommendations in pregnant women after bariatric surgery are not well investigated. This review summarizes current evidence, proposes clinical recommendations in pregnant women after bariatric surgery, and highlights areas of lack of evidence and the resulting urgent need for more clinical investigations.

The Epigenomic Analysis of Human Obesity

OBJECTIVE

Analysis of the epigenome-the chemical modifications and packaging of the genome that can influence or indicate its activity-enables molecular insight into cell type-specific machinery. It can, therefore, reveal the pathophysiological mechanisms at work in disease. Detected changes can also represent physiological responses to adverse environmental exposures, thus enabling the epigenetic mark of DNA methylation to act as an epidemiological biomarker, even in surrogate tissue. This makes epigenomic analysis an attractive prospect to further understand the pathobiology and epidemiological aspects of obesity. Furthermore, integrating epigenomic data with known obesity-associated common genetic variation can aid in deciphering their molecular mechanisms.

METHODS AND CONCLUSIONS

This review primarily examines epidemiological or population-based studies of epigenetic modifications in relation to adiposity traits, as opposed to animal or cell models. It discusses recent work exploring the epigenome with respect to human obesity, which to date has predominately consisted of array-based studies of DNA methylation in peripheral blood. It is of note that highly replicated BMI DNA methylation associations are not causal, but strongly driven by coassociations for more precisely measured intertwined outcomes and factors, such as hyperlipidemia, hyperglycemia, and inflammation. Finally, the potential for the future exploration of the epigenome in obesity and related disorders is considered.

Pregnancy after bariatric surgery: improving outcomes for mother and child

The significant increase in the prevalence of obesity has led to an increase in the number of obese women who become pregnant. In this setting, in recent years, there has been an exponential rise in the number of bariatric procedures, with approximately half of them performed in women of childbearing age, and a remarkable surge in the number of women who become pregnant after having undergone bariatric surgery (BS). These procedures entail the risk of nutritional deficiencies, and nutrition is a crucial aspect during pregnancy. Therefore, knowledge and awareness of the consequences of these techniques on maternal and fetal outcomes is essential. Current evidence suggests a better overall obstetric outcome after BS, in comparison to morbid obese women managed conservatively, with a reduction in the prevalence of gestational diabetes mellitus, pregnancy-associated hypertensive disorders, macrosomia, and congenital defects. However, the risk of potential maternal nutritional deficiencies and newborns small for gestational age cannot be overlooked. Results concerning the incidence of preterm delivery and the number of C-sections are less consistent. In this paper, we review the updated evidence regarding the impact of BS on pregnancy.

Differential methylation in inflammation and type 2 diabetes genes in siblings born before and after maternal bariatric surgery

OBJECTIVE

Siblings born before (BMS) and after (AMS) maternal biliopancreatic diversion (BPD) show differences in the methylome. The objective was to use a sibling-pair design to examine the effects from interpregnancy weight loss as a consequence of maternal bariatric surgery, other than BPD, on the methylome comparing BMS and AMS.

METHODS

Women with at least one child born before and one after bariatric surgery were identified in Swedish national registers. Whole blood samples from BMS (N = 31) and AMS (N = 31) siblings were collected for epigenetic methylation analysis while maternal information was collected from antenatal medical records.

RESULTS

In total 3,074 genes, with corresponding 23,449 CpG methylation sites, were differently methylated and associated with an overrepresentation of differently methylated CpG sites in genes involved with insulin receptor signaling, type 2 diabetes signaling, and leptin signaling in obesity, while the most significant differently methylated genes were HLA-DQA1, HLA-DQB1, and TSPAN18, when comparing BMS and AMS siblings.

CONCLUSIONS

These results suggest that maternal bariatric surgery, with subsequent weight loss between pregnancies, is associated with alterations in the methylome of genes involved in insulin receptor signaling, type 2 diabetes signaling, and leptin signaling in obesity in a comparison of BMS and AMS siblings.

A short-term transition from a high-fat diet to a normal-fat diet before pregnancy exacerbates female mouse offspring obesity

BACKGROUND/OBJECTIVES

Recent findings have highlighted the detrimental influence of maternal overnutrition and obesity on fetal development and early life development. However, there are no evidence-based guidelines regarding the optimal strategy for dietary intervention before pregnancy.

SUBJECTS/METHODS

We used a murine model to study whether switching from a high-fat (HF) diet to a normal-fat (NF) diet (H1N group) 1 week before pregnancy could lead to in utero reprogramming of female offspring obesity; comparator groups were offspring given a consistent maternal HF group or NF group until weaning. After weaning, all female offspring were given the HF diet for either 9 or 12 weeks before being killed humanely.

RESULTS

H1N treatment did not result in maternal weight loss before pregnancy. NF offsprings were neither obese nor glucose intolerant during the entire experimental period. H1N offsprings were most obese after the 12-week postweaning HF diet and displayed glucose intolerance earlier than HF offsprings. Our mechanistic study showed reduced adipocyte insulin receptor substrate 1 (IRS1) and hepatic IRS2 expression and increased adipocyte p-Ser(636/639) and p-Ser(612) of H1N or HF offspring compared with that in the NF offspring. Among all groups, the H1N offspring had lowest level of IRS1 and the highest levels of p-Ser(636/639) and p-Ser(612) in gonadal adipocyte. In addition, the H1N offspring further reduced the expression of Glut4 and Glut2, vs those of the HF offspring, which was lower compared with the NF offspring. There were also enhanced expression of genes inhibiting glycogenesis and decreased hepatic glycogen in H1N vs HF or NF offspring. Furthermore, we showed extremely higher expression of lipogenesis and adipogenesis genes in gonadal adipocytes of H1N offspring compared with all other groups.

CONCLUSIONS

Our results suggest that a transition from an HF diet to an NF diet shortly before pregnancy, without resulting in maternal weight loss, is not necessarily beneficial and may have deleterious effects on offspring.

Maternal pre-pregnancy BMI and gestational weight gain, offspring DNA methylation and later offspring adiposity: findings from the Avon Longitudinal Study of Parents and Children

Background: Evidence suggests that in utero exposure to undernutrition and overnutrition might affect adiposity in later life. Epigenetic modification is suggested as a plausible mediating mechanism.

Methods: We used multivariable linear regression and a negative control design to examine offspring epigenome-wide DNA methylation in relation to maternal and offspring adiposity in 1018 participants.

Results: Compared with neonatal offspring of normal weight mothers, 28 and 1621 CpG sites were differentially methylated in offspring of obese and underweight mothers, respectively [false discovert rate (FDR)-corrected P-value < 0.05), with no overlap in the sites that maternal obesity and underweight relate to. A positive association, where higher methylation is associated with a body mass index (BMI) outside the normal range, was seen at 78.6% of the sites associated with obesity and 87.9% of the sites associated with underweight. Associations of maternal obesity with offspring methylation were stronger than associations of paternal obesity, supporting an intrauterine mechanism. There were no consistent associations of gestational weight gain with offspring DNA methylation. In general, sites that were hypermethylated in association with maternal obesity or hypomethylated in association with maternal underweight tended to be positively associated with offspring adiposity, and sites hypomethylated in association with maternal obesity or hypermethylated in association with maternal underweight tended to be inversely associated with offspring adiposity.

Conclusions: Our data suggest that both maternal obesity and, to a larger degree, underweight affect the neonatal epigenome via an intrauterine mechanism, but weight gain during pregnancy has little effect. We found some evidence that associations of maternal underweight with lower offspring adiposity and maternal obesity with greater offspring adiposity may be mediated via increased DNA methylation.

Mitigating or exacerbating effects of maternal-fetal programming of female mice through the food choice environment

Humans live, eat, and become overweight/obese in complex surroundings where there are many available food choices. Prenatal exposure to poor food choices predisposes offspring to increased negative health risks, including obesity. Many animal experiments have analyzed intergenerational body weight parameters in an environment without food choices, which may not be directly translatable to the human food environment. In this study, offspring from mothers with a defined high-fat diet (HFD) or low-fat diet (LFD) were arbitrarily assigned to either an exclusively LFD or HFD or to a diet where they have a choice between LFD and HFD (choice diet). Offspring displayed negative outcomes of increased body weight, body fat, serum leptin, and blood glucose levels when given the choice diet compared with offspring on the LFD. Conversely, improved energy expenditure was found for offspring given the choice diet compared with offspring from HFD dams given LFD. In addition, maternal diet-specific influences on offspring metabolic parameters were identified, especially in offspring from HFD dams, including positive outcomes of reduced leptin in LFD offspring, reduced corticosterone and cholesterol levels in HFD offspring, and increased exercise levels in choice offspring, as well as the negative outcome of increased calorie intake in LFD offspring from HFD dams. This defined model can now be used as the basis for future studies to characterize the cycle of inter- and intragenerational obesity and whether more realistic diet environments, especially those including choice, can mitigate phenotype.

Overweight and Obesity before, during and after Pregnancy: Part 2: Evidence-based Risk Factors and Interventions

Overweight and obesity have become a global health problem. Obesity and excessive weight gain during pregnancy have a serious impact on maternal, fetal and neonatal outcomes. Pre-conceptional obesity and excessive weight gain during pregnancy are associated with weight gain in women following childbirth leading to associated risks such as metabolic syndrome, cardiovascular disease and diabetes. Long-term risks for the offspring are an increased risk for early cardiovascular events, metabolic syndrome and decreased life expectancy as adults. German health care has not yet adequately responded to this development. There are no clinical guidelines for obesity before, during or after pregnancy, there are no concerted actions amongst midwives, obstetricians, health advisors, politicians and the media. Research projects on effective interventions are lacking although health care concepts would be urgently needed to reduce future metabolic and cardiovascular risks for women and children as well as to minimize the associated costs for the society.