Maternal obesity, uterine activity, and the risk of spontaneous preterm birth

Cervical length screening among low-risk women; relationship of body mass index on cervical length and risk of preterm birth

BACKGROUND

Preterm birth (PTB) contributes to nearly 11% of all deliveries in the world. The majority of spontaneous preterm birth (sPTB) remains unexplained. Risk factors include abnormal body mass index (BMI), short cervical length, comorbidities and many more. However, there is limited study on the association between body mass index, cervical length and preterm birth in Malaysia among low-risk women. Hence, we aim to examine the relationship between body mass index, cervical length and the risk of spontaneous preterm birth.

METHOD

In this prospective cohort study, pregnant women between 16 and 24 weeks who fulfilled the criteria were recruited. Women with history of preterm birth were excluded. Demographic and clinical data (age, BMI, ethnicity, education level and parity) were obtained. Cervical length was measured using transvaginal scan. Patients were then followed up till delivery to determine their delivery gestation and outcome of delivery.

RESULTS

Out of 153 women who participated in this study, 146 women had cervical length of more than 30 mm, six had cervical length between 25 mm and 30 mm and one had cervical length of 24 mm. There were nine (9) cases of sPTB, with all of them being late preterm with normal midtrimester cervical length. Almost half of them (44%) were overweight/obese. A significant association was found between age, cervical length, and parity compared to BMI. Nevertheless, no significant association was seen between the BMI and risk of sPTB.

CONCLUSION

This study demonstrates a higher BMI is associated with longer cervical length, but it is not necessarily protective against sPTB. Hence, we concluded there is a limited role in cervical length screening among low-risk women regardless of their BMI in predicting sPTB.

Differences in cervical length during the second trimester among normal weight, overweight and obese women: A systematic review and meta-analysis

Objective

Maternal obesity has been previously linked to increased risk of preterm birth; however, the actual pathophysiology behind this observation remains unknown. Cervical length seems to differentiate among overweight, obese and extremely obese patients, compared to normal weight women. However, to date the actual association between body mass index and cervical length remains unknown. In this systematic review, accumulated evidence is presented to help establish clinical implementations and research perspectives.

Methods

We searched Medline, Scopus, the Cochrane Central Register of Controlled Trials CENTRAL, Google Scholar, and Clinicaltrials.gov databases from inception till February 2023. Observational studies that reported on women undergone ultrasound assessment of their cervical length during pregnancy were included, when there was data regarding their body mass index. Statistical meta-analysis was performed with RStudio. The quality of the included studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS).

Results

Overall, 20 studies were included in this systematic review and 12 in the meta-analysis. Compared to women with normal weight, underweight women were not associated with increased risk of CL < 15 mm or < 30 mm and their mean CL was comparable (MD -1.51; 95% CI -3.07, 0.05). Overweight women were found to have greater cervical length compared to women with normal weight (MD 1.87; 95% CI 0.52, 3.23) and had a lower risk of CL < 30 mm (OR 0.65; 95% CI 0.47, 0.90).

Conclusion

Further research into whether BMI is associated with cervical length in pregnant women is deemed necessary, with large, well-designed, prospective cohort studies with matched control group.

A review of maternal overweight and obesity and its impact on cardiometabolic outcomes during pregnancy and postpartum

The rates of maternal overweight and obesity, but also excess gestational weight gain, are increasing. Pregnancy complications, including gestational diabetes mellitus, gestational hypertension, pre-eclampsia and delivery of a preterm or growth restricted baby, are higher for both women with overweight and obesity and women who gain excess weight during their pregnancy. Other conditions such as polycystic ovary syndrome are also strongly linked to overweight and obesity and worsened pregnancy complications. All of these conditions place women at increased risk for future cardiometabolic diseases. If overweight and obesity, but also excess gestational weight gain, can be reduced in women of reproductive age, then multiple comorbidities associated with pregnancy complications may also be reduced in the years after childbirth. This narrative review highlights the association between maternal overweight and obesity and gestational weight gain, with gestational diabetes, pre-eclampsia, polycystic ovary syndrome and delivery of a preterm or growth restricted baby. This review also addresses how these adverse conditions are linked to cardiometabolic diseases after birth. We report that while the independent associations between obesity and gestational weight gain are evident across many of the adverse conditions assessed, whether body mass index or gestational weight gain is a stronger driving factor for many of these is currently unclear. Mechanisms linking gestational diabetes mellitus, gestational hypertension, pre-eclampsia, preterm delivery and polycystic ovary syndrome to heightened risk for cardiometabolic diseases are multifactorial but relate to cardiovascular and inflammatory pathways that are also found in overweight and obesity. The need for post-partum cardiovascular risk assessment and follow-up care remains overlooked. Such early detection and intervention for women with pregnancy-related complications will significantly attenuate risk for cardiovascular disease.

Association of Maternal Prepregnancy Body Mass Index With Fetal Growth and Neonatal Thalamic Brain Connectivity Among Adolescent and Young Women

Importance

Higher maternal prepregnancy body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) is associated with adverse long-term outcomes for offspring, including obesity, poorer cognitive and social abilities, and increased risk of psychiatric disorders. Less clear is whether higher maternal BMI disrupts fetal growth and brain development.

Objective

To investigate the association of maternal prepregnancy BMI with fetal growth and neonatal functional connectivity.

Design, Setting, and Participants

This prospective longitudinal cohort study was conducted from 2012 to 2017. Participants included nulliparous pregnant adolescent and young adult women, aged 14 to 19 years who were recruited in the second trimester through Columbia University Irving Medical Center and Weill Cornell Medical College. Women received routine prenatal care and had no major health problems at the time of recruitment. Data were analyzed from January 2018 to March 2020.

Exposures

Maternal prepregnancy BMI.

Main Outcomes and Measures

The main outcomes were fetal growth, measured as estimated fetal weight, and neonatal functional connectivity, measured using magnetic resonance imaging. Prepregnancy BMI and fetal ultrasonographic measurements were obtained from electronic health record review. Resting-state brain imaging data were acquired in infants within the first month of postnatal life. Functional connectivity was measured using intrinsic functional distribution and seed-based methods.

Results

Among 129 women recruited, 105 had ultrasonographic data from at least 2 points and were included in analyses. The mean (SD) age at delivery was 17.82 (1.31) years. Maternal prepregnancy BMI was positively associated with the slope of estimated fetal weight (β = 0.668; 95% CI, 0.163 to 1.175; P = .01) but not with fetal head circumference (β = -0.004; 95% CI, -0.024 to 0.016; P = .70). In a subsample of 45 infants with magnetic resonance imaging data, maternal prepregnancy BMI was positively correlated with global connectivity in the left thalamus. Using this thalamic region as a seed, higher maternal BMI was associated with greater local thalamic (both hemispheres) and lower frontothalamic connectivity.

Conclusions and Relevance

These results suggest that maternal prepregnancy BMI was associated with the development of regulation of body weight and thalamic functional brain connectivity in offspring even during fetal development.

Risk factors for failed induction of labor among pregnant women with Class III obesity

INTRODUCTION

Our aim was to identify risk factors for failed induction in morbidly obese patients undergoing the induction of labor at term.

MATERIAL AND METHODS

This was a retrospective multicenter study on a cohort of 235 patients with a body mass index greater than 40 kg/m² and giving birth to a singleton in cephalic presentation, who had an induction of labor from 38 weeks of amenorrhea. Scheduled cesareans and spontaneous vaginal deliveries were excluded. Maternal, peri-partum and neonatal characteristics were analyzed according to the delivery route.

RESULTS

In all, 235 patients were included. Of these, 62.5% patients delivered vaginally and 37.5% by cesarean section. The frequency of nulliparity was greater in patients who had a cesarean section (56 [interquartile range, IQR, 38.1] vs 56 [IQR 63.6], P < .001). In multivariate analysis, nulliparity (odds ratio [OR] 2.81, 95% confidence interval [CI] 1.58-4.97], P < .001), low Bishop's score (OR .794, 95% CI .70-.90, P < .001) and weight gain (OR 1.04, 95% CI 1.01-1.08, P = .033) were independent risk factors for failed induction. Umbilical cord pH at birth lower than 7 (0 vs 7 [IQR 8.0], P < .001) and lower than 7.20 (36 [IQR 24.5] vs 35 [IQR 39.8], P = .014) as well as the Apgar at 1 minute (14 [IQR 9.5] vs 17 [IQR 19.3], P = .032) was significantly higher in infants born by cesarean section.

CONCLUSIONS

In this cohort, 63% of women with Class III obesity had successful inductions of labor; risk factors for failed induction include nulliparity and unfavorable Bishop score.

Adiponectin links maternal metabolism to uterine contractility

Adiponectin is secreted by adipose tissue and promotes insulin sensitivity. Low circulating adiponectin is associated with increased risk for preterm labor, but the influence of adiponectin on uterine myometrial physiology is unknown. We hypothesized that adiponectin receptors (AdipoRs) decrease myometrial contractility via AMPK to promote uterine quiescence in pregnancy. Using quantitative RT-PCR, we found that nonpregnant or pregnant human and mouse myometrium express AdipoR1 and AdipoR2 mRNAs. We confirmed AdipoR2 protein expression in human and mouse myometrium, with increased abundance in late mouse pregnancy. Both recombinant adiponectin and a pharmacologic AdipoR agonist, AdipoRon, potently inhibited uterine myometrial strip contractions in physiologic organ bath. The relaxation was independent of contractile stimulus (oxytocin, KCl, U46619). AdipoR agonists increased AMPK phosphorylation in pregnant mouse myometrium, and the direct AMPK activator A769662 also relaxed myometrial strips. However, the AMPK inhibitor dorsomorphin (compound C) blocked AMPK phosphorylation but did not abolish relaxation with either AdipoRon or A769662. In summary, adiponectin inhibits myometrial contractility consistent with the possibility that it is a previously unrecognized link between maternal metabolism and pregnancy maintenance. We also identify a separate role for AMPK regulating myometrial contractions that may influence labor onset.-Vyas, V., Guerra, D. D., Bok, R., Powell, T., Jansson, T., Hurt, K. J. Adiponectin links maternal metabolism to uterine contractility.

Adiponectin and Omentin Levels as Predictive Biomarkers of Preterm Birth in Patients with Gestational Diabetes Mellitus

Objective

The aim of this study was to determine any changes in adiponectin and omentin levels in GDM patients who delivered at term and preterm and to evaluate whether adipokines can be useful as a clinical biomarker to predict subsequent preterm delivery.

Patients and Methods

The levels of adiponectin and omentin were measured in four groups: (1) women with GDM who delivered at term (n=63); (2) women with GDM who had the symptoms of threatened preterm labor and delivered at term (n=23); (3) women with GDM and spontaneous preterm birth (before 37 completed weeks of gestation) (n=19); (4) women with physiological pregnancy (n=55).

Results

In comparison with control group the median adiponectin concentrations were significantly lower in all GDM groups (10737 versus 8879; 7057; 6253 ng/ml, respectively; p<0.01). The median omentin concentrations were also significantly lower in all GDM groups in comparison with control group (469 versus 432; 357; 308 ng/ml, respectively; p<0.01). No significant differences in adiponectin and omentin levels between the GDM, preterm labor, and preterm birth groups were observed. However, there was a trend towards lower adiponectin and omentin levels in preterm birth group. The strong correlations between adiponectin and omentin levels were observed in all groups (R=0.801, p<0.001; R=0.824, p<0.001; R=0.705, p<0.001; R=0.764, respectively; p<0.001). In the univariable logistic regression model, significant correlation between omentin concentrations and preterm birth occurrence was found.

Conclusions

Our findings suggest that omentin-1, rather than adiponectin, could be useful as a predictor of preterm birth in patients with gestational diabetes mellitus.

Maternal body mass index and cervical length among women with a history of spontaneous preterm birth†

Objectives: To evaluate whether women with a prior spontaneous preterm birth (SPTB) with a higher body mass index (BMI) have a lower risk of a shortened cervix in a subsequent pregnancy.Study Design: A secondary analysis of the Maternal-Fetal Medicine Units Network RCT of omega-3 fatty acid supplementation for recurrent SPTB prevention. All women had ≥1 prior SPTB <37 weeks, a singleton pregnancy, and initiated 17-alpha hydroxyprogesterone caproate(17-OHPC). The primary exposure was pre-pregnancy BMI. The primary outcome was the shortest transvaginal cervical length <30 mm.Results: Of the 356 women with a prior SPTB receiving 17-OHPC and a cervical length available, 108 (30%) were overweight and 103 (29%) obese; 12% had a cervical length <30 mm. Fewer overweight/obese women had a shortened cervix compared to normal-weight women (43 versus 57%; odds ratio: 0.47 [95%CI: 0.25-0.89]). After adjusting for maternal age, number of prior SPTBs, and tobacco use, overweight/obese women were less than half as likely to have a shortened cervix compared to normal-weight women (adjusted odds ratio: 0.46, 95%CI: 0.24-0.89).Conclusions: Overweight and obese women with a prior SPTB receiving 17-OHPC have longer cervical lengths compared to normal weight women, and this finding could explain a possible mechanism between the decreased rate of SPTB and larger BMI.

Induction of the apoptotic pathway by oxidative stress in spontaneous preterm birth: Single nucleotide polymorphisms, maternal lifestyle factors and health status

The purpose of the present study was to search for associations between spontaneous preterm birth (sPTB), single nucleotide polymorphisms (SNPs) associated with the apoptotic pathway as triggered by oxidative stress, maternal lifestyle and health status. SNP genotyping [rs7560 for c-Jun N-terminal kinase (JNK), rs9517320 for mammalian STE20-like protein kinase 3 (MST3), rs1049216 for caspase 3 (CASP3)] in the placenta and maternal blood of 300 controls with at-term birth and 43 cases of sPTB was performed. No association was identified in genotype frequencies or combinations of foetal/maternal genotypes between single SNPs and sPTB. The risk of sPTB was significantly reduced by physical activity and significantly increased by current hypertensive diseases, premature rupture of membranes (PROM) or preterm PROM (P-PROM) and previous sPTB. The TT/GA genotype of JNK/CASP3 in maternal blood and maternal health status (current hypertensive diseases, current PROM/P-PROM, previous sPTB) were independently associated with sPTB. The present findings suggested that, independently of other maternal factors, pregnant women carrying the TT/GA genotype of JNK/CASP3 were more susceptible to sPTB than women bearing the GT/GA (our reference) genotype; that the apoptotic pathway triggered by oxidative stress was involved; and that genetic and non-genetic factors contributed to sPTB. Knowledge of these aspects may aid to improve the management of pregnancies by indicating the lifestyle to be adopted on the basis of sPTB susceptibility.

Association among Maternal Obesity, Cervical Length, and Preterm Birth

Objective The objective of this study was to determine if mid-trimester cervical length is associated with the inverse relationship between maternal body mass index (BMI) at delivery and spontaneous preterm birth (SPTB). Materials and Methods This was a retrospective cohort of women with a singleton pregnancy without prior SPTB who underwent routine transvaginal cervical length assessment between 18 and 24 weeks. Women were categorized into four BMI groups: (1) 18.5 to 24.9, (2) 25 to 29.9, (3) 30 to 34.9, and (4) ≥ 35 kg/m2. Univariable and multivariable analyses were conducted to determine whether BMI group was associated with SPTB at < 37, 34, or 32 weeks independent of the cervical length. Results Of the 18,100 women in this analysis, 43.5% had a BMI ≥ 30. In univariable analysis, increasing BMI group was associated with longer cervical length but not with cervical length < 10th percentile. SPTB at < 37, 35, and 32 weeks was less common among women with higher BMI. In multivariable regression, a higher BMI group was associated with a lower frequency of SPTB at 37 weeks (adjusted odds ratios [aORs] of 0.64, 0.68, and 0.51), at 34 weeks (aORs of 0.53, 0.54, and 0.31) and at 32 weeks (aORs of 0.47, 0.60, and 0.27) for BMI groups 2 to 4, respectively. This association persisted even when cervical length was entered into the model as a covariate. Conclusion Women with a higher BMI group had longer mid-trimester cervical length, and correspondingly reduced SPTB. However, the decreased risk of SPTB was not associated with cervical length. The reason for the potential protective effect from prematurity is unknown and its mechanisms require further investigation.

Intrapartum Management of the Obese Gravida

Obese women are at increased risk for multiple labor abnormalities, including postdates pregnancy, failed induction of labor, prolonged labor, cesarean delivery, and postpartum hemorrhage (PPH). Prolonged labor among obese women is confined to the first stage of labor. In the setting of reassuring fetal and maternal status, increased time to progress in the first stage of labor should be allowed. Uterine atony occurs more frequently in obese women and vigilance in the prevention of PPH is critical. There is a lack of high-quality data to guide the management of induction, labor, and PPH prevention among obese women.

Synergistic effect of maternal obesity and periodontitis on preterm birth in women with pre-eclampsia: a prospective study

AIM

The aim of this study was to investigate if pregnant women with both obesity and periodontitis are more likely to experience preterm birth (PTB) in women with pre-eclampsia (PE) than pregnant women with only obesity or only periodontitis.

MATERIALS AND METHODS

The study examined a total of 328 pregnant women at 21-24 weeks of gestation. Overweight and obesity was defined based on criteria proposed by the WHO Expert Consultation. Periodontal conditions were assessed by measuring periodontal clinical attachment loss. PTB was defined as delivery at <37 weeks, and PE was defined as blood pressure higher than 140/90 mmHg on two separate occasions with at least 1+ proteinuria on a random urine screen after the 20th week of pregnancy.

RESULTS

After adjusting for other important cofactors, pregnant women with periodontitis were 5.56 times [95% confidence interval (CI) = 1.22-25.39] more likely to have PTB with PE than women without periodontitis. The association was much stronger (odds ratio = 15.94, 95% CI = 3.31-76.71) in women with both obesity and periodontitis.

CONCLUSIONS

Our results of this study indicate that pregnant women with both pre-pregnancy obesity and periodontitis are significantly more likely to have PTB with PE than pregnant women with only periodontitis.

Maternal Obesity and its Short- and Long-Term Maternal and Infantile Effects

Obesity, in childhood or in adulthood, remains to be a global health problem. The worldwide prevalence of obesity has increased in the last few decades, and consequently, the women of our time suffer more gestational problems than women in the past. The prevalence of obesity is greater in older women than in younger ones and in women with low educational level than in their counterparts with a higher level of education. Maternal obesity during pregnancy may increase congenital malformations and neonatal morbidity and mortality. Maternal obesity is associated with a decreased intention to breastfeed, decreased initiation of breastfeeding, and decreased duration of breastfeeding. We discuss the current epidemiological evidence for the association of maternal obesity with congenital structural neural tube and cardiac defects, fetal macrosomia that predisposes infants to birth injuries and to problems with physiological and metabolic transition, as well as potential for long-term complications secondary to prenatal and neonatal programming effects compounded by a reduction in sustained breastfeeding.

The Impact of Maternal Body Mass Index and Gestational Age on the Detection of Uterine Contractions by Tocodynamometry: A Retrospective Study

OBJECTIVE

To examine the impact of maternal body mass index (BMI) and gestational age (GA) on uterine contraction detection by tocodynamometry.

METHODS

Gravidas with preterm labor (PTL) complaints who were evaluated by tocodynamometry, discharged from Labor and Delivery triage, and subsequently readmitted for preterm delivery were studied. Forty-six patients in whom contractions were detected (group 1) were compared to 49 women in whom contractions were not detected (group 2) with respect to BMI and GA at both evaluation and delivery. Multivariable logistic regression was used to adjust for confounders.

RESULTS

Group 2 had a higher mean BMI (31.7 vs 26.1, P < .001), were more likely to be obese (57.1% vs 19.6%, P < .001), and were more likely to have been evaluated in the mid-trimester (36.7% vs 17.4%, P = .04) compared to group 1. Independent risk factors for the inability of the tocodynamometer to detect contractions were obesity (odds ratio [OR] 0.18, 95% confidence interval [CI] 0.07-0.46) and evaluation in the mid-trimester (OR 0.33, 95% CI 0.13-0.84).

CONCLUSION

Our study provides evidence that the effectiveness of tocodynamometry diminishes with increasing maternal BMI. Efficacy of tocodynamometry is also decreased at earlier GA, most pronounced below 25 weeks. To evaluate women with PTL symptoms in the mid-trimester or symptomatic obese women at any GA, a modality other than tocodynamometry could be valuable to more accurately assess uterine activity.

Design of lifestyle intervention trials to prevent excessive gestational weight gain in women with overweight or obesity

OBJECTIVE

The Lifestyle Interventions for Expectant Moms (LIFE-Moms) Consortium is designed to determine, in pregnant women with overweight or obesity, whether various behavioral and lifestyle interventions reduce excessive gestational weight gain (GWG) and subsequent adverse maternal and neonatal outcomes and obesity in offspring. The design and planning process of the LIFE-Moms Consortium is described.

METHODS

The LIFE-Moms Consortium is a collaboration among seven clinical centers, a Research Coordinating Unit, and the NIH designed to support each clinical center's conduct of a separate trial of a unique intervention. Specific common measures, procedures, and eligibility criteria are consistent across the seven trials allowing data to be combined in exploratory analyses and/or compared readily.

RESULTS

Numerous committees and working groups were created to define common measures and outcomes during pregnancy and through 1 year postpartum, develop Consortium policies, and oversee progress of the trials. The primary outcome for the Consortium is excessive GWG. Secondary outcomes include maternal, neonatal, and infant anthropometric measures, physical activity, sleep, and complications of pregnancy and delivery.

CONCLUSIONS

A multi-center consortium of independent, lifestyle interventions with common measures and outcomes may enhance the ability to identify promising interventions for improving outcomes in pregnant women and their offspring.

Adipokinins in pregnancies at risk of preterm delivery

OBJECTIVE

To compare adipokinins between women experiencing preterm labor (PTL) and prior preterm deliveries (PTD).

STUDY DESIGN

In this prospective observational cohort, 110 women with a singleton <35 weeks at increased risk of PTD were studied. Serum leptin, adiponectin, and resistin were obtained at three times (23-34 weeks, 35-36 weeks, at delivery) and analyzed via enzyme-linked immunosorbent assay. The adipokinins were compared across time and between PTL (n = 59) and prior PTD (n = 51) groups using generalized estimated equation models.

RESULTS

There were no differences in leptin, adiponectin, or resistin levels over the three times between the PTL and PTD groups. There was a trend toward higher leptin levels (p = 0.06 unadjusted analysis, p = 0.09 adjusted analysis) at 23-34 weeks. When stratified by body mass index (BMI), there were differences in leptin (p < 0.001 for BMI < 30; p = 0.77 for BMI ≥ 30) and adiponectin (p = 0.04 for BMI < 30; p = 0.09 for BMI ≥ 30), but not in resistin over the three times between the PTL and prior PTD groups.

CONCLUSION

There were no significant differences in adipokinins in women with PTL and a prior PTD. The trends toward higher leptin levels at 23-34 weeks in women with PTL may represent a compensatory response and require further evaluation in the study of treatments for PTL.

Risks associated with obesity in pregnancy, for the mother and baby: a systematic review of reviews

Maternal obesity is linked with adverse outcomes for mothers and babies. To get an overview of risks related to obesity in pregnant women, a systematic review of reviews was conducted. For inclusion, reviews had to compare pregnant women of healthy weight with women with obesity, and measure a health outcome for mother and/or baby. Authors conducted full-text screening, quality assurance using the AMSTAR tool and data extraction steps in pairs. Narrative analysis of the 22 reviews included show gestational diabetes, pre-eclampsia, gestational hypertension, depression, instrumental and caesarean birth, and surgical site infection to be more likely to occur in pregnant women with obesity compared with women with a healthy weight. Maternal obesity is also linked to greater risk of preterm birth, large-for-gestational-age babies, foetal defects, congenital anomalies and perinatal death. Furthermore, breastfeeding initiation rates are lower and there is greater risk of early breastfeeding cessation in women with obesity compared with healthy weight women. These adverse outcomes may result in longer duration of hospital stay, with concomitant resource implications. It is crucial to reduce the burden of adverse maternal and foetal/child outcomes caused by maternal obesity. Women with obesity need support to lose weight before they conceive, and to minimize their weight gain in pregnancy.

Cell-Free Fetal DNA, Telomeres, and the Spontaneous Onset of Parturition

Multiple previous reports have provided compelling support for the premise that spontaneous parturition is mediated by activation of inflammation-related signaling pathways leading to increased secretion of cytokines and chemokines, the influx of neutrophils and macrophages into the pregnant uterus, increased production of uterine activation proteins (eg, connexin-43, cyclo-oxygenase-2, oxytocin receptors, etc), activation of matrix metalloproteinases, and the release of uterotonins leading to cervical ripening, membrane rupture, and myometrial contractions. The missing link has been the fetal/placental signal that triggers these proinflammatory events in the absence of microbial invasion and intrauterine infection. This article reviews the biomedical literature regarding the increase in cell-free fetal DNA (cffDNA), which is released during apoptosis in the placenta and fetal membranes at term, the ability of apoptosis modified vertebrate DNA to stimulate toll-like receptor-9 (TLR9) leading to increased release of cytokines and chemokines, and the potential "fail-safe" role for the anti-inflammatory cytokine IL-10. This article also reviews the literature supporting the key role that telomere loss plays in regard to increasing the ability of vertebrate (including placental) DNA to stimulate TLR9, and in regard to signaling the onset of apoptosis in the placenta and fetal membranes, thereby providing a biologic clock that determines the length of gestation and the timing for the onset of parturition. In summary, this literature review provides a strong rationale for future research to test the hypothesis that telomere loss and increased cffDNA levels trigger the proinflammatory events leading to the spontaneous onset of parturition in mammals: the "cffDNA/telomere hypothesis."

Metabolic syndrome in preeclampsia women in gorgan

The aim of study was to assess the metabolic syndrome in preeclampsia women. The study was performed on 50 women. The metabolic syndrome prevalence was 66%. Serum glucose, triglyceride and LDL-cholesterol levels significantly were increased and HDL- cholesterol level significantly was decreased in metabolic syndrome patients. These patients showed high prevalence of components of the syndrome. Our results show the importance of dyslipidemia in preeclampsia in overweight and obese women. Preeclampsia and cardiovascular disease are important problems for the health of women. It may be useful to give a treat to people with a high-normal blood pressure in early pregnancy.

Urinary metabolic profiles in early pregnancy are associated with preterm birth and fetal growth restriction in the Rhea mother-child cohort study

BACKGROUND

Preterm birth (PB) and fetal growth restriction (FGR) convey the highest risk of perinatal mortality and morbidity, as well as increasing the chance of developing chronic disease in later life. Identifying early in pregnancy the unfavourable maternal conditions that can predict poor birth outcomes could help their prevention and management. Here we used an exploratory metabolic profiling approach (metabolomics) to investigate the association between birth outcomes and metabolites in maternal urine collected early in pregnancy as part of the prospective mother-child cohort Rhea study. Metabolomic techniques can simultaneously capture information about genotype and its interaction with the accumulated exposures experienced by an individual from their diet, environment, physical activity or disease (the exposome). As metabolic syndrome has previously been shown to be associated with PB in this cohort, we sought to gain further insight into PB-linked metabolic phenotypes and to define new predictive biomarkers.

METHODS

Our study was a case-control study nested within the Rhea cohort. Major metabolites (n = 34) in maternal urine samples collected at the end of the first trimester (n = 438) were measured using proton nuclear magnetic resonance spectroscopy. In addition to PB, we used FGR in weight and small for gestational age as study endpoints.

RESULTS

We observed significant associations between FGR and decreased urinary acetate (interquartile odds ratio (IOR) = 0.18 CI 0.04 to 0.60), formate (IOR = 0.24 CI 0.07 to 0.71), tyrosine (IOR = 0.27 CI 0.08 to 0.81) and trimethylamine (IOR = 0.14 CI 0.04 to 0.40) adjusting for maternal education, maternal age, parity, and smoking during pregnancy. These metabolites were inversely correlated with blood insulin. Women with clinically induced PB (IPB) had a significant increase in a glycoprotein N-acetyl resonance (IOR = 5.84 CI 1.44 to 39.50). This resonance was positively correlated with body mass index, and stratified analysis confirmed that N-acetyl glycoprotein and IPB were significantly associated in overweight and obese women only. Spontaneous PB cases were associated with elevated urinary lysine (IOR = 2.79 CI 1.20 to 6.98) and lower formate levels (IOR = 0.42 CI 0.19 to 0.94).

CONCLUSIONS

Urinary metabolites measured at the end of the first trimester are associated with increased risk of negative birth outcomes, and provide novel information about the possible mechanisms leading to adverse pregnancies in the Rhea cohort. This study emphasizes the potential of metabolic profiling of urine as a means to identify novel non-invasive biomarkers of PB and FGR risk.

Predictors of failed trial of labor among women with an extremely obese body mass index

OBJECTIVE

The purpose of this study was to examine predictors associated with cesarean delivery (CD) among extremely obese women undergoing a trial of labor (TOL).

STUDY DESIGN

Using a delivery database, we identified all pregnant women delivering at our institution from Jan. 1, 2008, through July 31, 2010, weighing >275 lb at the time of delivery who attempted a TOL with a singleton gestation >34 weeks' gestation. Demographic and obstetrical factors were compared for those having a successful vaginal delivery to those having a CD.

RESULTS

During the study period, there were 357 pregnant women who weighed >275 lb (all with body mass index [BMI] >40 kg/m(2)), and among these, 248 (69.5%) attempted a TOL. Women having a CD had a greater BMI (51.6 vs 49.9 kg/m(2), P = .038), were less likely to be parous (32.2% vs 65.8%, P < .0001), and were more likely to be induced (80.5% vs 57.8%) compared to those having a vaginal delivery. Using a multivariable logistic regression model, among nulliparous women, maternal age, parity, and cervical dilation at time of admission were independent predictors for CD. Furthermore, an increase in BMI of 10 kg/m(2) was associated with a 3.5 increased odds (P = .002) for CD.

CONCLUSION

Among nulliparous extremely obese women attempting a TOL, BMI was an independent predictor of CD, with the rate of CD increasing further with increasing BMI. The underlying mechanisms for failed TOL in the setting of maternal obesity remain largely unknown.

Autism spectrum disorder in children born preterm-role of exposure to perinatal inflammation

Autism Spectrum Disorder (ASD) is the collective term for neurodevelopmental disorders characterized by qualitative impairments in social interaction, communication, and a restricted range of activities and interests. Many countries, including Australia, have reported a dramatic increase in the number of diagnoses over the past three decades, with current prevalence of ASD at 1 in every 110 individuals (~1%). The potential role for an immune-mediated mechanism in ASD has been implicated by several studies, and some evidence suggests a potential link between prenatal infection-driven inflammation and subsequent development of ASD. Furthermore, a modest number of contemporary studies have reported a markedly increased prevalence of ASD in children born preterm, who are at highest risk of exposure to perinatal inflammation. However, the mechanisms that underpin the susceptibility to infection-driven inflammation during pregnancy and risk of preterm birth, and how these intersect with the subsequent development of ASD in the offspring, is not understood. This review aims to summarize and discuss the potential mechanisms and evidence for the role of prenatal infection on the central nervous system, and how it may increase the susceptibility for ASD pathogenesis in children born preterm.

Association between body mass index and pregnancy outcome in a randomized trial of cerclage for short cervix

OBJECTIVE

To evaluate whether increasing body mass index (BMI) alters the efficacy of ultrasound-directed cerclage in women with a history of preterm birth.

METHODS

This was a planned secondary analysis of a multicenter trial in which women with a singleton gestation and prior spontaneous preterm birth (17 to 33 + 6 weeks' gestation) were screened for a short cervix by serial transvaginal ultrasound evaluations between 16 and 22 + 6 weeks. Women with a short cervix (cervical length < 25 mm) were randomly assigned to cerclage or not. Linear and logistic regression were used to assess the relationship between BMI and continuous and categorical variables, respectively.

RESULTS

Overall, in the screened women (n = 986), BMI was not associated with cervical length (P = 0.68), gestational age at delivery (P = 0.12) or birth at < 35 weeks (P = 0.68). For the cerclage group (n = 148), BMI had no significant effect. For the no-cerclage group (n = 153), BMI was associated with a decrease in gestational age at delivery, with an estimated slope of - 0.14 weeks per kg/m(2) (P = 0.03; including adjustment for cervical length). This result was driven primarily by several women with BMI > 47 kg/m(2) .

CONCLUSION

In women at high risk for recurrent preterm birth, BMI was not associated with cervical length or gestational age at birth. BMI did not appear to adversely affect ultrasound-indicated cerclage.

Effect of revised IOM weight gain guidelines on perinatal outcomes

OBJECTIVE

We sought to examine perinatal outcomes in women with a body mass index (BMI) of 25 kg/m(2) comparing those whose weight gain met 2009 IOM guidelines to women meeting 1990 IOM guidelines.

METHODS

This is a retrospective cohort study utilizing birth records linked to hospital discharge data for all term, singleton infants born to overweight, Missouri residents (2000-2006) with a BMI of 25 kg/m(2). We excluded congenital anomalies, mothers with diabetes, hypertension, or previous cesarean delivery.

RESULTS

Fourteen thousand nine hundred fifty-five women gained 25-35 lbs (1990 guidelines); 1.6% delivered low birth weight (LBW) infants and 1.1% delivered macrosomic infants. Eight thousand three hundred fifty women gained 15-25 lbs (2009 guidelines); 3.4% delivered LBW infants and 0.6% delivered macrosomic infants. Women who gained 15-25 lbs were 1.99 (95% CI 1.67, 2.38) times more likely to have a LBW infant and 0.59 (95% CI 0.40, 0.76) times less likely to deliver a macrosomic infant.

CONCLUSION

Limiting weight gain in women with a BMI of 25 kg/m(2), per the 2009 guidelines, increases the risk of LBW deliveries and decreases the risk of macrosomia but does not reduce associated adverse perinatal outcomes. Further studies should explore the optimal weight gain to reduce these outcomes.

Obesity and pregnancy: clinical management of the obese gravida

In recent years, the prevalence of obesity in the United States has risen dramatically, especially among women of reproductive age. Research that has specifically evaluated pregnancy outcomes among obese parturients has allowed for a better understanding of the myriad adverse perinatal complications that are observed with significantly greater frequency in the obese pregnant population. The antepartum, intrapartum, intraoperative, postoperative, and postpartum periods are all times in which the obese pregnant woman is at greater risk for adverse maternal-fetal outcomes, compared with her ideal bodyweight counterpart. Comorbid medical conditions that commonly are associated with obesity further accentuate perinatal risks. All obese pregnant women should be counseled regarding these risks, and strategies should be used to improve perinatal outcome whenever possible. Obese women of reproductive age ideally should be counseled before conception and advised to achieve ideal bodyweight before pregnancy.

Overweight and obesity in pregnancy do not adversely affect neonatal outcomes: new evidence

We studied neonatal outcomes of infants of obese mothers in a cohort of 6,125 deliveries, using logistic multivariate analysis to remove the role of potential confounding variables. Although, as in previous reports, the crude unadjusted prevalence of several adverse neonatal outcomes was higher in these infants, the multivariable analysis revealed that only two outcomes remained significantly associated with maternal overweight and obesity: neonatal macrosomia (adjusted odds ratios aOR 1.4, p < 0.001) and meconium aspiration syndrome (aOR 1.6, p = 0.05), indicating that the unadjusted association with the other outcomes was caused by confounding factors. Nonetheless, as macrosomia is associated with increased health risks both to the mothers and their infants, and maternal obesity with considerable maternal morbidity during pregnancy, these results should not lead to complacency, but instead encourage better prevention of obesity in general and during pregnancy in particular.

Effect of maternal body mass index on in vitro response to tocolytics in term myometrium

OBJECTIVE

We sought to investigate the effect of body mass index (BMI) on in vitro response to tocolytics.

STUDY DESIGN

Myometrial biopsies were obtained at the time of scheduled cesarean deliveries from term nonlaboring women with BMI < or =29.9 (26.3 +/- 1.3; n = 7), 30-34.9 (31.8 +/- 1.2; n = 16), and > or = 35 (39.5 +/- 4.9; n = 9). Tissue strips were suspended in organ chambers for isometric tension recording. The effects of cumulative doses (10(-10) to 10(-5) mol/L) of nifedipine or indomethacin on spontaneous uterine contractility were determined. Areas under the contraction curve were compared using 1-way analysis of variance with Tukey post hoc test.

RESULTS

Myometrial response to tocolytics did not differ between the BMI groups. Nifedipine, but not indomethacin, significantly inhibited myometrial contractility independent of BMI.

CONCLUSION

BMI does not affect uterine response to tocolytics in isolated uterine tissue from term nonlaboring women.

Obstetric management of obesity in pregnancy

Rates of obesity among the pregnant population have increased substantially and adiposity has a damaging effect on every aspect of female reproductive life. This review summarises epidemiological data concerning obesity-related complications of pregnancy. Obesity is linked to a number of adverse obstetric outcomes as well as increased maternal and neonatal morbidity and mortality. These complications include miscarriage, congenital abnormalities, pre-eclampsia, gestational diabetes mellitus, iatrogenic preterm delivery, postdates pregnancy with increased rates of induction of labour, caesarean section, postpartum haemorrhage, shoulder dystocia, infection, venous thromboembolism, and increased hospital stay. It is important to consider obese pregnant women as a high risk group with a linear increase in risk of complications associated with their degree of obesity. Their obstetric management should be consultant-led and involve a multidisciplinary team approach to improve outcome.

Maternal obesity: consequences for children, challenges for clinicians and carers

In many industrialised countries almost one in five pregnant women is obese. Maternal obesity has major implications for the fetus and newborn infants, and may have adverse consequences for lifelong health and well-being. We discuss the current epidemiological evidence for the association of maternal obesity with congenital structural neural tube and cardiac defects, fetal macrosomia that predisposes infants to birth injuries and to problems with physiological and metabolic transition, as well as potential for long-term effects secondary to prenatal and neonatal programming effects compounded by a reduction in sustained breastfeeding. We summarise the evidence for the effect of maternal weight management interventions on fetal and neonatal outcomes and discuss areas where further research is needed to clarify uncertainties.

Obesity in older mothers, gestational weight gain, and risk estimates for preterm phenotypes

OBJECTIVE

To assess whether advanced maternal age modifies the relationship between maternal pregravid weight status, gestational weight gain patterns, and the occurrence of spontaneous preterm birth (SPB) and medically indicated preterm birth (MIPB).

METHODS

Retrospective cohort analysis of vital statistics data from the state of Florida for the period 2004 through 2007 comprising 311,422 singleton pregnancies (two age groups: 20-24 years old or younger women and >or=35 years or older women). Mothers were classified into five clusters based on their pre-pregnancy body mass index (BMI) values: non-obese (less than 30), class I obese (30.0<or=BMI<or=34.9), class II obese (35.0<or=BMI<or=39.9), class III obese (40<or=BMI<or=49.9), and super-obese (BMI>or=50.0).

RESULTS

MIPB occurred more frequently among older than younger women [11.8% vs. 6.4%, respectively (p<0.0001)) whereas SPB occurred more frequently among younger women [11.3% vs. 10.5%, respectively (p<0.0001)). Maternal obesity increased the risk for MIPB but not for SPB. Regardless of BMI status, the risk of MIPB was elevated among older mothers, particularly among those with suboptimal (<0.23 kg/week) and supraoptimal (>0.68 kg/week) gestational weight gain. A dose-response relationship with increasing gestational weight gain was evident (p<0.01); the greatest risk for MIPB occurred among older mothers with weekly gestational weight gain in excess of 0.79 kg (OR=7.76, 95% CI=5.73-10.5).

CONCLUSION

The occurrence of medically indicated preterm birth is positively associated with increased maternal pregravid body weight, older maternal age and extremes of gestational weight gain. Targeted pre- and inter-conception weight management efforts should be particularly encouraged in older mothers.

Metabolic syndrome in early pregnancy and risk of preterm birth

The authors determined the association between metabolic syndrome in early pregnancy (mean, 11.96 weeks) and the risk of preterm birth in the mother-child cohort study ("Rhea" Study) in Crete, Greece, 2007-2009. Maternal fasting serum samples were collected, and blood pressure was measured at the time of the first major ultrasound examination (n = 625). Multivariable log-binomial regression models were used. Women with metabolic syndrome were at high risk for preterm birth (relative risk (RR) = 2.93, 95% confidence interval (CI): 1.53, 5.58), with the highest risk observed for medically indicated preterm births (RR = 5.13, 95% CI: 1.97, 13.38). Among the components of metabolic syndrome, the most significant risk factor was hypertension (RR = 2.32, 95% CI: 1.28, 4.20). An elevation of 10 mm Hg in diastolic blood pressure increased the relative risk for preterm birth by 29% (RR = 1.29, 95% CI: 1.08, 1.53), while a per unit increase in the low density lipoprotein/high density lipoprotein cholesterol ratio increased this risk by 19% (RR = 1.19, 95% CI: 1.02, 1.39). Fetal weight growth restriction was associated with elevated levels of insulin (RR = 1.14, 95% CI: 1.08, 1.20) and diastolic blood pressure (RR = 1.27, 95% CI: 1.00, 1.61) in early pregnancy. These findings suggest that women with metabolic syndrome in early pregnancy had higher risk for preterm birth.