Obesity and pregnancy: complications and cost

Maternal metabolism and obesity: modifiable determinants of pregnancy outcome

BACKGROUND

Obesity among pregnant women is highly prevalent worldwide and is associated in a linear manner with markedly increased risk of adverse outcome for mother and infant. Obesity in the mother may also independently confer risk of obesity to her child. The role of maternal metabolism in determining these outcomes and the potential for lifestyle modification are largely unknown.

METHODS

Relevant studies were identified by searching PubMed, the metaRegister of clinical trials and Google Scholar without limitations. Sensitive search strategies were combined with relevant medical subject headings and text words.

RESULTS

Maternal obesity and gestational weight gain have a significant impact on maternal metabolism and offspring development. Insulin resistance, glucose homeostasis, fat oxidation and amino acid synthesis are all disrupted by maternal obesity and contribute to adverse outcomes. Modification of lifestyle is an effective intervention strategy for improvement of maternal metabolism and the prevention of type 2 diabetes and, potentially, gestational diabetes.

CONCLUSIONS

Maternal obesity requires the development of effective interventions to improve pregnancy outcome. Strategies that incorporate a detailed understanding of the maternal metabolic environment and its consequences for the health of the mother and the growth of the child are likely to identify the best approach.

Obesity and gestational diabetes

The prevalence of both obesity and gestational diabetes mellitus (GDM) is increasing worldwide. GDM affects about 7% of all pregnancies and is defined as any degree of impaired glucose tolerance during gestation. The presence of obesity has a significant impact on both maternal and fetal complications associated with GDM. These complications can be addressed, at least in part, by good glycaemic control during pregnancy. The significance and impact of obesity in women with GDM are discussed in this article, together with treatment options, the need for long-term risk modification and postpartum follow-up.

Obesity in pregnancy: outcomes and economics

Maternal obesity is an important aspect of reproductive care. It is the commonest risk factor for maternal mortality in developed countries and is also associated with a wide spectrum of adverse pregnancy outcomes. Maternal obesity may have longer-term implications for the health of the mother and infant, which in turn will have economic implications. Efforts to prevent, manage and treat obesity in pregnancy will be costly, but may pay dividends from reduced future economic costs, and subsequent improvements to maternal and infant health. Decision-makers working in this area of health services should understand whether the problem can be reduced, at what cost; and then, what cost savings and health benefits will accrue in the future from a reduction of the problem.

Obesity in pregnancy: prevalence and metabolic consequences

Rates of obesity have increased exponentially worldwide to almost epidemic proportions. This is associated with a marked increase in adverse maternal and perinatal outcomes and subsequent burden on health care resources. In particular, maternal obesity is linked to numerous metabolic complications including subfertility, gestational diabetes, hypertensive disorders of pregnancy and thromboembolism with potential long-term health consequences for both mother and child. The underlying pathophysiology linking maternal obesity and adverse outcomes is complex but is likely to involve alterations in glucose and lipid metabolism, inflammation, perturbances in adipokines and vascular dysfunction all seen in obese women. Intervention studies are underway to determine whether alteration of maternal lifestyle can improve maternal and fetal outcomes.

Maternal obesity and neonatal Apgar scores

OBJECTIVE

To determine whether maternal obesity in early pregnancy is associated with low neonatal 5-min Apgar scores while adjusting for confounders.

METHODS

Data were obtained from Maine State Birth Records Database. Analyses were restricted to information on 58,089 white women and their newborns. Maternal weight status was defined using the recorded early second trimester maternal body mass index (BMI) and defined as normal weight (BMI <25), overweight (BMI 25 to <30), obese (BMI 30 to <40), and morbidly obese (BMI >or=40). Logistic regression analysis was used to assess the association of maternal weight status with low Apgar score while adjusting for confounders.

RESULTS

Compared with newborns of normal weight women, the risk to receive low Apgar scores (4-6) is increased in newborns of obese (OR 1.4, 95% CI 1.1-1.7) and morbidly obese mothers (OR 2.0, 95% CI 1.5-2.7). The association did not achieve significance for newborns of overweight mothers (OR 1.2, 95% CI 0.99-1.4). No association was identified between maternal weight status and very low Apgar scores (0-3).

CONCLUSIONS

Maternal obesity is associated with a significantly increased risk for decreased Apgar scores at birth. Further studies are needed to clarify the relationships among maternal obesity, complications of pregnancy, and neonatal outcome.

Maternal dietary glycemic intake and the risk of neural tube defects

Both maternal diabetes and obesity have been associated with an increased risk of neural tube defects (NTD), possibly due to a sustained state of hyperglycemia and/or hyperinsulinemia. Data were collected in the Boston University Slone Birth Defects Study (a case-control study) from 1988 to 1998. The authors examined whether high dietary glycemic index (DGI) and high dietary glycemic load (DGL) increased the risk of NTDs in nondiabetic women. Mothers of NTD cases and nonmalformed controls were interviewed in person within 6 months after delivery about diet and other exposures. Odds ratios and 95% confidence intervals were estimated from logistic regression for high DGI (> or =60) and high DGL (> or =205), with cutpoints determined by cubic spline. Of 698 case mothers, 25% had high DGI and 4% had high DGL. Of 696 control mothers, 15% had high DGI and 2% had high DGL. After adjustment for sociodemographic factors and other dietary factors, the odds ratio for high DGI was 1.5 (95% confidence interval: 1.1, 2.0); for high DGL, it was 1.8 (95% confidence interval: 0.8, 4.0). Diets with proportionally high DGI or DGL may put the developing fetus at risk of an NTD, adding further evidence that hyperglycemia lies within the pathogenic pathway.

Vitamin D insufficiency is prevalent among pregnant African American adolescents

STUDY OBJECTIVE

Recent attention has focused on vitamin D insufficiency but few data exist on vitamin D status among pregnant minority youth.

DESIGN

A screening study was undertaken in adolescents having prenatal blood samples drawn for other routine tests obtained during the second trimester (18+/-1.8 week gestation, n=44) or third trimester of pregnancy (28.4+/-2.1 week gestation, n=36). Serum 25- hydroxyvitamin D (25(OH)D) was measured and significant determinants of vitamin D insufficiency in this cohort were identified.

SETTING

Urban prenatal clinic.

PARTICIPANTS

Eighty pregnant African American adolescents (< or = 18 y of age).

MAIN OUTCOME MEASURE(S)

Vitamin D status, STDs, hemoglobin, season, birth weight

RESULTS

Serum 25(OH)D in this group averaged 21.6+/-8 ng/mL (age 16.5+/-1.1 y, n=80), and did not significantly differ between the second (20.95+/-8.2 ng/mL, n=44) and third trimester cohorts (22.5+/-7.9 ng/mL, n=36). Vitamin D insufficiency (< 20 ng/mL) was evident in 46.25% and vitamin D deficiency (<15 ng/mL) was evident in 21.25% of those studied. Significant predictors of suboptimal vitamin D status included sampling during the winter months (P=0.004), lower hemoglobin concentration (P=0.019), and higher second trimester leptin levels (P=0.018). Inverse associations between 25(OH)D and bacterial vaginosis were evident when controlled for season of sampling (P=0.02, n=80).

CONCLUSIONS

Vitamin D insufficiency was prevalent among urban pregnant minority adolescents. Further studies are needed to address the impact of this finding on maternal and neonatal calcium homeostasis and bone health.

Maternal obesity is a potential source of error in mid-trimester ultrasound estimation of gestational age

OBJECTIVES

To investigate the possible impact of maternal obesity on ultrasonographic dating of pregnancy.

METHODS

The Swedish Medical Birth Registry was used to identify 842 083 singleton pregnancies for which the estimated date of delivery (EDD) according to last menstrual period (EDD-LMP) and according to ultrasound examination (EDD-US) and maternal body mass index (BMI) in early pregnancy were known. Dates were adjusted following ultrasound examination, negative adjustment representing pregnancies that were shorter according to ultrasound examination than they were according to LMP. Odds ratios (OR) were adjusted for year of birth, maternal age, parity and smoking.

RESULTS

The EDD was postponed at least 7 days (discrepancy between EDD-LMP and EDD-US of < or = -7 days) in 25.2% of all pregnancies. There was a statistically significant association between maternal BMI and discrepancy between EDD-LMP and EDD-US. Among pregnant women with a BMI > or = 30.0 kg/m(2), the risk of postponed EDD was significantly greater compared with women with a BMI of 20.0-24.9 kg/m(2). The EDD was more often postponed > or = 14 days (OR, 1.65; 95% CI, 1.60-1.70) or 7-13 days (OR, 1.45; 95% CI, 1.42-1.48) among women with a BMI > or = 30 kg/m(2) than among women with normal weight. Similar risk was observed among women with a BMI of 25.0-29.9 kg/m(2), but was less pronounced.

CONCLUSIONS

High maternal BMI increases the risk of postponing the EDD at mid-trimester ultrasound examination.

Gestational Diabetes Mellitus: An Opportunity to Prevent Type 2 Diabetes and Cardiovascular Disease in Young Women

In women with previous gestational diabetes (pGDM), the risk of developing Type 2 diabetes is greatly increased, to the point that GDM represents an early stage in the natural history of Type 2 diabetes. In addition, in the years following the index pregnancy, women with pGDM exhibit an increased cardiovascular risk profile and an increased incidence of cardiovascular disease. This paper will review current knowledge on the metabolic modifications that occur in normal pregnancy, underlining the mechanism responsible for GDM, the link between these alterations and the associated long-term maternal complications. In women with pGDM, accurate follow-up and prevention strategies (e.g., weight control and regular physical exercise) are needed to reduce the subsequent development of overt diabetes and other metabolic abnormalities related to cardiovascular disease. Therefore, our paper will provide arguments in favor of performing follow-up programs aimed at modifying risk factors involved in the pathogenesis of Type 2 diabetes and cardiovascular disease.

Review: Diabetes in pregnancy: insulin resistance, obesity and placental dysfunction

Obesity in pregnancy is linked to increased morbidity and mortality for mother and baby. The incidence of gestational diabetes is increased approximately two to six-fold in women who are overweight-obese and the presence of diabetes is a further metabolic challenge which is associated with adverse outcomes. Herein the role of obesity is discussed in the generation of insulin resistance and inflammation and its contribution to placental dysfunction.

Occupational physical activities, working hours and outcome of pregnancy: findings from the Southampton Women's Survey

OBJECTIVES

To investigate risks of physical activity at work by pregnancy trimester, including the effects on head and abdominal circumference.

METHOD

At 34 weeks of gestation we interviewed 1327 mothers from the prospective Southampton Women's Survey (SWS); we asked about their activities (working hours, standing/walking, kneeling/squatting, trunk bending, lifting and night shifts) in jobs held at each of 11, 19 and 34 weeks of gestation, and subsequently ascertained four birth outcomes (preterm delivery, small for gestational age (SGA) and reduced head or abdominal circumference) blinded to employment history.

RESULTS

Risk of preterm delivery was elevated nearly threefold in women whose work at 34 weeks entailed trunk bending for >1 h/day. Small head circumference was more common in babies born to women who worked for >40 h/week. However, no statistically significant associations were found with SGA or small abdominal circumference, and preterm delivery showed little association with long working hours, lifting, standing or shift work.

CONCLUSIONS

There is a need for more research on trunk bending late in pregnancy, and on the relationship of work to reduced head circumference. Our findings on several other occupational exposures common among pregnant workers are reassuring.

Pregnancy and obesity

Obesity has become a worldwide epidemic: it is associated with increased rate of infertility and with many pregnancy complications. Moreover, it is associated with gestational diabetes mellitus, which increases the risk of these complications. As the prevalence of obesity is increasing, so is the number of women in the reproductive age who are overweight and obese. This article addresses issues concerning pregravid obesity and weight gain during pregnancy and their implication on gestational diabetes and pregnancy outcome.

The factors affecting pregnancy outcomes in the second trimester pregnant women

Adequate nutrient intake during pregnancy is important to fetal and maternal health. The purpose of this study was to investigate the factors affecting birth weight and gestational age and to provide basic data to promote more favorable pregnancy outcomes. Data were collected from 234 pregnant women at two hospitals in Seoul. Demographic characteristics, anthropometric measurements and health related habits were obtained using a questionnaire at the hospital visit during the second trimester. Dietary intakes were estimated by 24 hour recall at the hospital visit during the second trimester. Data on pregnancy outcomes, including birth weights and gestational ages, were obtained from hospital records after delivery. Birth weights were divided into a low birth weight group (birth weight<3.1 kg), a normal birth weight group (3.1-3.6 kg) and a high birth weight group (>3.6 kg). Gestational ages were divided into tertiles according to the gestational age of the subjects: group 1 (<38.53 weeks), group 2 (38.53-40.00 weeks) and group 3 (>40.00 weeks). The number of family members was significantly lower in the low birth weight group than in the normal birth weight group (p<0.05). In the low birth weight group, pregnancy weight was significantly lower than in the high birth weight group (p<0.05). Health related habits were not significantly different among any of the groups. Intakes of fiber, phosphorous, iron, vitamin B₆ and folic acid were significantly higher in the high birth weight group than the low birth weight group (p<0.05). Gestational age was not significantly affected by nutrient intakes, but birth weight was affected by nutrient intake in the results of this study. Therefore, the adequacy of nutrient intake is important for the improvement of pregnancy outcomes.

The health and nutrition of young indigenous women in north Queensland – intergenerational implications of poor food quality, obesity, diabetes, tobacco smoking and alcohol use

Objective

To document nutritional status and health behaviours of young indigenous women of childbearing age in rural communities in north Queensland.

Design

Cross-sectional survey of 424 Aboriginal and 232 Torres Strait Islander (TSI) women aged 15–34 years, conducted in twenty-three rural and remote communities of far north Queensland in 1999–2000, with follow-up of a smaller cohort (n132) in 2006–2007.

Main outcome measures

Weight, waist circumference, intake of fruit and vegetables, smoking, alcohol intake, fasting blood glucose, blood pressure, HDL cholesterol, γ-glutamyltransferase, red cell folate (RCF), interval weight and waist gain and incidence of diabetes.

Results

Forty-one per cent of Aboriginal and 69 % of TSI had central obesity, 62 % were smokers, 71 % drank alcohol regularly and of those, 60 % did so at harmful levels. One third of Aboriginal and 16 % of TSI women had very low RCF levels. In the group followed up, there was a mean annual waist gain of 1·6 cm in Aboriginal women and 1·2 cm in TSI, 0·5 kg/m2in BMI and 1·5 kg in weight. Incidence of new type 2 diabetes mellitus in this cohort was 29·1 per 1000 person-years (py) (95 % CI 14·0, 52·8) in Aboriginal women and 13·9 per 1000 py (95 % CI 5·6, 28·5) among TSI.

Conclusions

High prevalence and incidence of central obesity and diabetes, poor nutrition, high rates of alcohol use and tobacco smoking together with young maternal age, provide a poor intra-uterine environment for many indigenous Australian babies, and contribute to high perinatal morbidity and future disability. Community level interventions to improve pre-pregnancy nutrition and health behaviours in young women are urgent.

Association of maternal pre-pregnancy weight with birth defects: evidence from a case-control study in Western Australia

BACKGROUND

Maternal obesity confers increased risks of poor pregnancy outcomes. There are limited Australian data on the risk of birth defects associated with maternal pre-pregnancy obesity.

METHODS

Population-based case-control study of 418 controls, 111 cases with heart defects (and of these, 38 had conotruncal heart defects), 27 with neural tube defects, 86 cases with urinary tract defects, 48 cases with orofacial clefts, and 20 with limb reduction defects. Maternal pre-pregnancy weight and height were self-reported.

RESULTS

Women with pre-pregnancy obesity (body mass index 30+) had a twofold increased odds of having an infant with neural tube defects, conotruncal heart defects, orofacial clefts and limb reduction defects and 30-40% increase in heart defects generally and urinary tract defects. None of the estimates was statistically significant.

CONCLUSIONS

Our findings were consistent with similar, statistically significant studies in the literature. Weight reduction prior to pregnancy in obese women may be a means of primary prevention of birth defects.

Determinantes nutricionais e sóciodemográficos da variação de peso no pós-parto: uma revisão da literatura

Trata-se de um estudo de revisão sobre os fatores nutricionais e sócio-demográficos da variação de peso no pós-parto. Foi realizada uma busca bibliográfica nas bases de dados eletrônicas Scientific Eletronic Library On-line (SciELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) e Medical Literature Analysis and Retrieval System Online (MEDLINE) referente a literatura publicada na última década (1997-2008). Treze artigos, um informe técnico e dois livros considerados relevantes sobre o assunto e publicados anteriormente ao ano 1997 foram citados na revisão. A revisão priorizou estudos de ensaios clínicos randomizados e de seguimento realizados com gestantes e mulheres no pós-parto. Os resultados obtidos mostram como principais fatores associados com a variação de peso no pós-parto o ganho de peso gestacional acima das recomendações do Institute of Medicine, Índice de Massa Corporal Pré-Gestacional > 25 kg/m2, dieta, tempo e intensidade do aleitamento materno e os fatores sócio-demográficos: raça negra, primiparidade, idade materna, baixa renda e baixa escolaridade. A prática regular de atividade física é recomendada como uma estratégia para evitar o ganho de peso excessivo e melhorar a perda de peso durante o pós-parto. No Brasil não existe uma estratégia nacional para prevenir o ganho de peso excessivo e garantir a adequada perda de peso nesse período. Durante o pós-parto, a maioria das ações de saúde visa basicamente garantir o aleitamento materno.

Early childhood health promotion and its life course health consequences

OBJECTIVE

To explore whether health promotion efforts targeted at preschool-age children can improve health across the life span and improve future economic returns to society.

METHODS

We selected 4 health topics to review-tobacco exposure, unintentional injury, obesity, and mental health-because they are clinically and epidemiologically significant, and represent the complex nature of health problems in this early period of life. The peer-reviewed literature was searched to assess the level of evidence for short- and long-term health impacts of health promotion and disease prevention interventions for children from before birth to age 5. This review sought to document the monetary burden of poor child health, the cost implications of preventing and treating child health problems, and the net benefit of the interventions.

RESULTS

The evidence is compelling that these 4 topics-tobacco exposure, unintentional injury, obesity, and mental health-constitute a significant burden on the health of children and are the early antecedents of significant health problems across the life span. The evidence for the cost consequences of these problems is strong, although more uneven than the epidemiological data. The available evidence for the effectiveness of interventions in this age group was strongest in the case of preventing tobacco exposure and injuries, was limited to smaller-scale clinical interventions in the case of mental health, and was least available for efforts to prevent obesity among preschoolers.

CONCLUSIONS

Currently available research justifies the implementation of health interventions in the prenatal to preschool period-especially to reduce tobacco exposure and prevent injuries. There is an urgent need for carefully targeted, rigorous research to examine the longitudinal causal relationships and provide stronger economic data to help policy makers make the case that the entire society will benefit from wise investment in improving the health of preschool-age children and their families.

A prospective study of pregnancy outcome and biomarkers of oxidative stress in nulliparous obese women

OBJECTIVE

We sought to investigate pregnancy outcome and biomarkers of oxidative stress in nulliparous obese pregnant women.

STUDY DESIGN

Pregnancy outcome and blood biomarkers were assessed prospectively in 385 obese nulliparous women from the placebo arm of a randomized controlled trial.

RESULTS

Body mass index was associated with higher rates of preeclampsia (PE) (P = .010) and cesarean section (P = .016). In all, 18.8% of infants were small for gestational age (< 10th adjusted birthweight centile), 13.4% were large for gestational age (> 90th centile), and 11.9% were preterm. The plasma ascorbic acid concentration was inversely related to small-for-gestational-age delivery (P < .025), and increased plasma triglyceride concentrations with later PE (P < .0001). Plasma uric acid concentration (P = .043) and the gamma- tocopherol:alpha-tocopherol ratio (P = .023) were related to body mass index.

CONCLUSION

A previously unreported risk of fetal growth restriction associated with reduced plasma ascorbic acid concentration was identified in nulliparous obese women. The high incidence of PE and preterm birth were unrelated to oxidative stress markers.

Time course of changes in serum oxidant/antioxidant status in overfed obese rats and their offspring

The aim of the present study was to determine the time course of changes in oxidant/antioxidant status, as well as serum glucose, insulin, leptin and lipid levels, liver adipose tissue and muscle lipid and protein contents, in cafeteria-diet-fed dams during gestation and lactation, and in their offspring throughout adulthood. Food intake was also evaluated. The cafeteria diet induced a significant increase in maternal body and relative adipose tissue weights, daily energy intake, and plasma glucose, insulin, leptin and lipid levels at parturition (day 0) and at the end of lactation (day 21). Plasma total antioxidant status [ORAC (oxygen radical absorbance capacity)], erythrocyte catalase and SOD (superoxide dismutase) activities were lower, whereas plasma hydroperoxide and carbonyl protein levels were higher in cafeteria-diet-fed mothers compared with control mothers at days 0 and 21. Pups from cafeteria-diet-fed dams, both males and females, also had consistently higher body and relative adipose tissue weights, and plasma glucose, insulin, leptin, triacylglycerol (triglyceride) and cholesterol levels at birth (day 0), weaning (day 21) and 3 months of age (day 90). These offspring had significantly lower ORAC and catalase activity, and higher plasma hydroperoxide and carbonyl protein levels and SOD activity at birth, at days 21 and 90 compared with control offspring. In conclusion, excessive maternal fat and energy intake can play an important role in the development of metabolic disorders in the offspring. Maternal oxidative stress may be among the responsible factors. Fetal oxidative stress may present an additional confounding influence and probably contributes to additional disorders, aggravating features of the metabolic syndrome. An improvement in maternal oxidant/antioxidant status during pregnancy and lactation, with adequate nutrition, could have beneficial effects on the progeny.

Maternal obesity: a review of interventions

BACKGROUND

Obesity has become a serious global public health issue and has consequences for nearly all areas of medicine. Within obstetrics, obesity not only has direct implications for the health of a pregnancy but also impacts on the weight of the child in infancy and beyond. As such, maternal weight may influence the prevalence and severity of obesity in future generations. Pregnancy has been identified as a key time to target a weight control or weight loss strategy to help curb the rapidly growing obesity epidemic. In addition, if delivered sensitively, pregnancy may be a good time to target health behaviour changes by using the extra motivation women tend to have at this time to maximise the health of their child.

AIM

This study reviews the current evidence for interventions to promote weight control or weight loss in women around the time of pregnancy. A comprehensive review of medical research--PubMed, Embase, Ovid Medline and the Cochrane Clinical Trials register--showed that despite numerous reports of the prevalence and complications of maternal obesity, few intervention strategies have been suggested.

CONCLUSION

This study finds that there is a deficiency of appropriately designed interventions for maternal obesity and it concludes by highlighting areas for developing a more effective strategy.

Pregnancy after bariatric surgery: no problem?

Bariatric surgery is highly effective for weight loss in morbid obesity. With the high prevalence of severe obesity in the developed world, and the acknowledgement of the effectiveness of these procedures by National Institute for Clinical Excellence (in the UK) and the Food and Drug Administration (in the USA), women with severe obesity will increasingly seek such treatment. As the majority of these patients are women of reproductive age, obstetricians will encounter these patients frequently during pregnancy. It is therefore important for obstetricians to gain an insight into the types of surgery performed, the potential complications, including nutritional deficiency, and appropriate management of pregnancy following weight-loss surgery. In general, bariatric surgery is associated with a reduction in obesity related complication, with no apparent increased risk of adverse perinatal outcomes.

The early origins of later obesity: pathways and mechanisms

Excess bodyweight is the sixth most important risk factor contributing to the overall burden of disease worldwide. In excess of a billion adults and 10% of all children are now classified as overweight or obese. The main adverse consequences of obesity are the metabolic syndrome, cardiovascular disease and type 2 diabetes and a diminished average life expectancy. It has been argued that the complex pathological processes underlying obesity reflect environmental and genetic interactions, and individuals from disadvantaged communities seem to have greater risks than more affluent individuals partly because of fetal and postnatal programming interactions. Abundant evidence indicates that the obesity epidemic reflects progressive secular and age-related decreases in physical activity, together with passive over-consumption of energy dense foods despite neurobiological processes designed to regulate energy balance. The difficulty in treating obesity, however, highlights the deficits in our current understanding of the pathophysiology which underlies the initiation and chronic nature of this disorder. Large population based studies in Europe and North America in healthy women and in women with gestational diabetes have demonstrated that there are clear relationships between maternal and fetal nutrient supply, fetal growth patterns and the subsequent risk of obesity and glucose intolerance in childhood and adult life. In this review we discuss the impact of fetal nutrition on the biology of the developing adipocyte and brain and the growing evidence base supporting an intergenerational cycle of obesity.

Type 2 diabetes in pregnancy: importance of optimized care before, during and after pregnancy

Women with Type 2 diabetes (T2DM) are an increasingly important part of the practice of obstetric medicine. The rising rates of obesity and advanced maternal age have resulted in a surge in the number of pregnant women with T2DM. The hyperglycaemia and associated conditions of the metabolic syndrome lead to poor obstetric outcome and impact on the long-term health of the mother and offspring. It is essential that women and care-givers recognize the seriousness of T2DM in pregnancy and strive to improve prepregnancy care, obstetric outcome and the long-term health of both the mother and child.

Dietary restraint and gestational weight gain

OBJECTIVE

To determine whether a history of preconceptional dieting and restrained eating was related to higher weight gains in pregnancy.

DESIGN

Dieting practices were assessed among a prospective cohort of pregnant women using the Revised Restraint Scale. Women were classified on three separate subscales as restrained eaters, dieters, and weight cyclers.

SUBJECTS

Participants included 1,223 women in the Pregnancy, Infection, and Nutrition Study.

MAIN OUTCOME MEASURES

Total gestational weight gain and adequacy of weight gain (ratio of observed/expected weight gain based on Institute of Medicine recommendations).

STATISTICAL ANALYSES PERFORMED

Multiple linear regression was used to model the two weight-gain outcomes, while controlling for potential confounders including physical activity and weight-gain attitudes.

RESULTS

There was a positive association between each subscale and total weight gain, as well as adequacy of weight gain. Women classified as cyclers gained an average of 2 kg more than noncyclers and showed higher observed/expected ratios by 0.2 units. Among restrained eaters and dieters, there was a differential effect by body mass index. With the exception of underweight women, all other weight status women with a history of dieting or restrained eating gained more weight during pregnancy and had higher adequacy of weight gain ratios. In contrast, underweight women with a history of restrained eating behaviors gained less weight compared to underweight women without those behaviors.

CONCLUSIONS

Restrained eating behaviors were associated with weight gains above the Institute of Medicine's recommendations for normal, overweight, and obese women, and weight gains below the recommendations for underweight women. Excessive gestational weight gain is of concern because of its association with postpartum weight retention. The dietary restraint tool is useful for identifying women who would benefit from nutritional counseling prior to or during pregnancy with regard to achieving targeted weight-gain recommendations.

The impact of maternal BMI status on pregnancy outcomes with immediate short-term obstetric resource implications: a meta-analysis

Obesity is rising in the obstetric population, yet there is an absence of services and guidance for the management of maternal obesity. This systematic review aimed to investigate relationships between obesity and impact on obstetric care. Literature was systematically searched for cohort studies of pregnant women with anthropometric measurements recorded within 16-weeks gestation, followed up for the term of the pregnancy, with at least one obese and one comparison group. Two researchers independently data-extracted and quality-assessed each included study. Outcome measures were those that directly or indirectly impacted on maternity resources. Primary outcomes included instrumental delivery, caesarean delivery, duration of hospital stay, neonatal intensive care, neonatal trauma, haemorrhage, infection and 3rd/4th degree tears. Meta-analysis shows a significant relationship between obesity and increased odds of caesarean and instrumental deliveries, haemorrhage, infection, longer duration of hospital stay and increased neonatal intensive care requirement. Maternal obesity significantly contributes to a poorer prognosis for mother and baby during delivery and in the immediate post-partum period. National clinical guidelines for management of obese pregnant women, and public health interventions to help safeguard the health of mothers and their babies are urgently required.

Effect of high-fat diet during gestation, lactation, or postweaning on physiological and behavioral indexes in borderline hypertensive rats

Maternal obesity is becoming more prevalent. We used borderline hypertensive rats (BHR) to investigate whether a high-fat diet at different stages of development has adverse programming consequences on metabolic parameters and blood pressure. Wistar dams were fed a high- or low-fat diet for 6 wk before mating with spontaneously hypertensive males and during the ensuing pregnancy. At birth, litters were fostered to a dam from the same diet group as during gestation or to the alternate diet condition. Female offspring were weaned on either control or "junk food" diets until about 6 mo of age. Rats fed the high-fat junk food diet were hyperphagic relative to their chow-fed controls. The junk food-fed rats were significantly heavier and had greater fat pad mass than those rats maintained on chow alone. Importantly, those rats suckled by high-fat dams had heavier fat pads than those suckled by control diet dams. Fasting serum leptin and insulin levels differed as a function of the gestational, lactational, and postweaning diet histories. Rats gestated in, or suckled by high-fat dams, or maintained on the junk food diet were hyperleptinemic compared with their respective controls. Indirect blood pressure did not differ as a function of postweaning diet, but rats gestated in the high-fat dams had lower mean arterial blood pressures than those gestated in the control diet dams. The postweaning dietary history affected food-motivated behavior; junk food-fed rats earned less food pellets on fixed (FR) and progressive (PR) ratio cost schedules than chow-fed controls. In conclusion, the effects of maternal high-fat diet during gestation or lactation were mostly small and transient. The postweaning effects of junk food diet were evident on the majority of the parameters measured, including body weight, fat pad mass, serum leptin and insulin levels, and operant performance.

Maternal obesity and pregnancy complications: a review

Obesity in women of reproductive age is increasing at an unprecedented rate in western societies. Maternal obesity is associated with an unequivocal increase in maternal and fetal complications of pregnancy. Excessive maternal weight gain in pregnancy also appears to be an independent risk factor, regardless of prepregnancy weight. Few guidelines exist regarding appropriate weight gain in pregnancy in obese women. We review the association of maternal obesity with pregnancy complications. We also suggest that appropriate diet and lifestyle intervention can enable women with severe prepregnancy obesity to safely achieve quite strict targets for limited weight gain in pregnancy.

Obesity, diabetes, and links to congenital defects: a review of the evidence and recommendations for intervention

OBJECTIVE

To review evidence on the link between obesity and diabetes in pregnant women and the incidence of birth defects. In addition, the article offers recommendations for facilitating the broader scale implementation of evidence-based approaches to preventing obesity, particularly among pregnant women.

METHODS

A review of the evidence, primarily from epidemiologic studies, linking obesity and obesity-related metabolic disturbances in pregnant women to a range of birth defects. It also reviews potential mechanisms by which obesity and diabetes during pregnancy lead to damage in the developing embryo and highlights some evidence-based approaches to prevention. Finally it reviews policy options for positively impacting obesity and diabetes in this population.

RESULTS

Obesity and diabetes are a growing problem in the US population. This problem is particularly acute among women of childbearing age because the combination of obesity and diabetes is toxic to the developing fetus, which each contributing independently to embryopathy.

CONCLUSIONS

There is an urgent need for a national strategy for combating the growing and related problems of obesity and diabetes in the population. This strategy needs to encompass a spectrum of tax breaks, economic incentives, legislation, and educational approaches in order to be effective.

Prepregnancy obesity prevalence in the United States, 2004-2005

OBJECTIVE

To provide a current estimate of the prevalence of prepregnancy obesity in the United States.

METHODS

We analyzed 2004-2005 data from 26 states and New York City (n = 75,403 women) participating in the Pregnancy Risk Assessment Monitoring System, an ongoing, population-based surveillance system that collects information on maternal behaviors associated with pregnancy. Information was obtained from questionnaires self-administered after delivery or from linked birth certificates; prepregnancy body mass index was based on self-reported weight and height. Data were weighted to provide representative estimates of all women delivering a live birth in each particular state.

RESULTS

In this study, about one in five women who delivered were obese; in some state, race/ethnicity, and Medicaid status subgroups, the prevalence was as high as one-third. State-specific prevalence varied widely and ranged from 13.9 to 25.1%. Black women had an obesity prevalence about 70% higher than white and Hispanic women (black: 29.1%; white: 17.4%; Hispanic: 17.4%); however, these race-specific rates varied notably by location. Obesity prevalence was 50% higher among women whose delivery was paid for by Medicaid than by other means (e.g., private insurance, cash, HMO).

CONCLUSION

This prevalence makes maternal obesity and its resulting maternal morbidities (e.g., gestational diabetes mellitus) a common risk factor for a complicated pregnancy.

Serum macrophage migration inhibitory factor in the prediction of preterm delivery

OBJECTIVE

Macrophage migration inhibitory factor is a soluble mediator that helps govern the interaction between cytokines and stress hormones (eg, cortisol). We determined whether maternal macrophage migration inhibitory factor levels predicted subsequent preterm delivery.

STUDY DESIGN

A nested case-control study measuring serum macrophage migration inhibitory factor concentration at 9-23 weeks' gestation in women who ultimately delivered preterm (n = 60) compared with control women who delivered at term (n = 122). We also examined the connection of macrophage migration inhibitory factor with self-reported psychosocial variables.

RESULTS

Macrophage migration inhibitory factor was elevated in the preterm delivery cases (P = .0004), and log macrophage migration inhibitory factor concentration showed a graded response relationship with likelihood of preterm delivery. High-macrophage migration inhibitory factor was also associated with maternal risk-taking behavior, which itself was a risk factor for preterm delivery. Macrophage migration inhibitory factor remained associated independently with preterm delivery after adjusting regression models for several other preterm delivery risk factors (odds ratio, 3.11, 95% confidence interval, 1.54-6.30).

CONCLUSION

High-serum macrophage migration inhibitory concentration in early to midpregnancy is linked with subsequent preterm delivery.

Maternal obesity and risk of neural tube defects: a metaanalysis

We conducted a metaanalysis of published evidence on the relationship between maternal obesity and the risk of neural tube defects (NTDs). Eligible studies were identified from 3 sources: (1) PubMed search of articles that were published from January 1980 through January 2007, (2) reference lists of publications that were selected from the PubMed search, and (3) reference lists of review articles on obesity and maternal outcomes that were published from January 2000 through January 2007. Twelve studies met inclusion criteria. A Bayesian random effects model was used for the metaanalysis and metaregression. Unadjusted odds ratios for an NTD-affected pregnancy were 1.22 (95% CI, 0.99-1.49), 1.70 (95% CI, 1.34-2.15), and 3.11 (95% CI, 1.75-5.46) among overweight, obese, and severely obese women, respectively, compared with normal-weight women. None of the study characteristics included in the metaregression analysis affected the results significantly. Maternal obesity is associated with an increased risk of an NTD-affected pregnancy.

[Very preterm birth: should we be interested in maternal pre-pregnancy body mass index?]

Link between maternal body mass index (BMI) and pregnancy outcome is not clear.

OBJECTIVE

To appreciate the impact of prepregnancy maternal BMI on very preterm birth (22-32 gestation's weeks).

SECONDARY OBJECTIVE

To assess how maternal BMI does explain the mechanism of very preterm birth among live births.

METHODS

Population-based study, including each mother with a live or stillborn baby was included in a geographically defined (Poitou-Charentes and Franche-comté, France) case-control study in 2004 to 2006. Leanness (BMI<18.5kg/m(2)) and overweight and obesity (BMI> or =25kg/m(2)) were defined according to World Health Organization's standards. Statistical analysis consisted in a polynomial regression on 832 mothers of very preterm babies and 431 mothers of full-term babies, taking account for confounders as maternal age, birth country, educational level, maternal work and smoking during the pregnancy.

RESULTS

Leanness is a risk factor for very preterm live birth (aOR=1.73 [1.12-2.68]), overweight is a risk factor for stillbirth. (aOR=1.71 [1.03-2.84]). Among mothers of live born babies, leanness is a risk factor for spontaneous preterm birth (aOR=2.12 [1.20-3.74]), whereas overweight is a risk factor for very preterm birth on medical decision due to gestational hypertension (aOR=2.85 [1.80-4.52]).

CONCLUSION

Morbid maternal stoutness before pregnancy is a complex risk factor for very preterm delivery. Women and couples should be informed and practitioners should be aware in order to prevent and manage this pathological status.

Association between obesity during pregnancy and increased use of health care

BACKGROUND

In the United States, obesity during pregnancy is common and increases obstetrical risks. An estimate of the increase in use of health care services associated with obesity during pregnancy is needed.

METHODS

We used electronic data systems of a large U.S. group-practice health maintenance organization to identify 13,442 pregnancies among women 18 years of age or older at the time of conception that resulted in live births or stillbirths. The study period was between January 1, 2000, and December 31, 2004. We assessed associations between measures of use of health care services and body-mass index (BMI, defined as the weight in kilograms divided by the square of the height in meters) before pregnancy or in early pregnancy. The women were categorized as underweight (BMI <18.5), normal (BMI 18.5 to 24.9), overweight (BMI 25.0 to 29.9), obese (BMI 30.0 to 34.9), very obese (BMI 35.0 to 39.9), or extremely obese (BMI > or =40.0). The primary outcome was the mean length of hospital stay for delivery.

RESULTS

After adjustment for age, race or ethnic group, level of education, and parity, the mean (+/-SE) length of hospital stay for delivery was significantly (P<0.05) greater among women who were overweight (3.7+/-0.1 days), obese (4.0+/-0.1 days), very obese (4.1+/-0.1 days), and extremely obese (4.4+/-0.1 days) than among women with normal BMI (3.6+/-0.1 days). A higher-than-normal BMI was associated with significantly more prenatal fetal tests, obstetrical ultrasonographic examinations, medications dispensed from the outpatient pharmacy, telephone calls to the department of obstetrics and gynecology, and prenatal visits with physicians. A higher-than-normal BMI was also associated with significantly fewer prenatal visits with nurse practitioners and physician assistants. Most of the increase in length of stay associated with higher BMI was related to increased rates of cesarean delivery and obesity-related high-risk conditions.

CONCLUSIONS

Obesity during pregnancy is associated with increased use of health care services.

State of the Art Reviews: Nutrition and Lifestyle for a Healthy Pregnancy

Nutrition and lifestyle factors can maximize health in pregnancy and lower future risk of disease for both mother and fetus. Education can make a big difference for patients in pregnancy outcomes, anxiety, and future health. Pregnancy is a time when attention to proper weight gain can reduce the risk of future obesity, diabetes, hyperlipidemia, and cardiovascular disease. There is mounting evidence that fetal “programming” for future risk of disease begins in utero and varies with nutritional exposures during different times of pregnancy, although the exact mechanisms remain to be elucidated. It is clear that a few simple precautions and enhancements of diet and lifestyle can prevent birth defects and perinatal infections and may reduce future health risks. Exercise in pregnancy is safe and should be encouraged for healthy women.

Maternal obesity: pregnancy complications, gestational weight gain and nutrition

The obesity epidemic affects all, including women of reproductive age. One in five women attending prenatal care in the UK is obese. Prepregnancy obesity is associated with serious short- and long-term complications for mother and child. Furthermore, gestational weight gain (GWG) of obese pregnant women generally exceeds the Institute of Medicine recommended ranges. This observation can partially be explained by an unbalanced diet and lack of daily physical activity. Despite this, few lifestyle intervention trials in obese pregnant women are available. Two out of seven intervention trials focusing on GWG, nutrition and physical activity, reached a significant decrease in GWG. Developing guidelines to promote appropriated weight gain and healthy lifestyle in overweight and obese pregnant women remains a challenge. This review aims to summarize the complications associated with maternal prepregnancy overweight and obesity and to discuss possible strategies to improve the lifestyle habits of pregnant women.

Prevention of gestational diabetes by metformin plus diet in patients with polycystic ovary syndrome

OBJECTIVE

To prospectively assess whether metformin diet safely provides primary and secondary prevention of gestational diabetes (GD).

DESIGN

Assess development of GD on metformin diet.

SETTING

Outpatient clinical research center.

PATIENT(S)

One hundred forty-two nondiabetic women with polycystic ovary syndrome (PCOS) who had at least one live-birth (LB) pregnancy on metformin diet (172 pregnancies, 180 LBs).

INTERVENTION(S)

Women were given 26% protein, 44% carbohydrate diets, without calorie restriction during pregnancy. Metformin (2-2.55 g/d) was given preconception, through pregnancy.

MAIN OUTCOME MEASURE(S)

Development of GD.

RESULT(S)

On metformin, GD developed in 12 (7%) of 172 LB pregnancies. Forty-seven women had at least one previous LB pregnancy (n = 64) without metformin, with GD developing in 19 (30%). Subsequently, on metformin, these 47 women had 50 LB pregnancies, developing GD in 6 (12%), which was a statistically significant difference. Of 15 women who had previous GD without metformin, GD developed in 5 (31%) of 16 subsequent pregnancies on metformin. Of 32 women who were previously free of GD without metformin, GD developed in 1 (3%) of 34 subsequent pregnancies on metformin. Previous GD without metformin was the only statistically significant explanatory variable for current GD on metformin.

CONCLUSION(S)

Metformin diet during pregnancy in women with PCOS facilitates primary and secondary prevention of GD.

Impact of maternal body mass index on obstetric outcome

AIM

The purpose of the present study was to correlate effect of maternal body mass index (BMI) on obstetric outcome. The studies conducted so far are from Western developed countries and there is a paucity of data from developing countries.

METHODS

A prospective evaluation was carried out of 380 women in one unit of a tertiary care teaching hospital in North India from May 2005 to June 2006 on the effect of maternal BMI on pregnancy outcome. BMI was calculated as weight (kg) divided by height (m(2)). BMI was used to characterize women as lean (BMI < 19.8 kg/m(2)), normal (BMI 19.9-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)) or obese (> or =30 kg/m(2)).

RESULTS

Forty-six women (12.1%) out of 380 were underweight, 99 (26.1%) were overweight, 30 (7.9%) were obese and the remaining 205 (53.9%) had normal BMI. Anemia (P = 0.02) and low birthweight (P = 0.008) was significantly present among lean women. Obese women had a significant risk for gestational diabetes (P = 0.0004), pre-eclampsia (P = 0.004), cesarean delivery (P = 0.01) and macrosomia (P = 0.02).

CONCLUSION

Both lean and obese women carry a risk for adverse pregnancy outcome, therefore pregnant women should maintain a normal BMI to achieve a healthy pregnancy outcome.