Bariatric surgery and associated adverse pregnancy outcomes among obese women

Objective: To evaluate whether bariatric surgery is associated with intrauterine growth restriction (IUGR).

Methods: We performed a population-based retrospective cohort study to estimate the relationship between prior bariatric surgery and adverse pregnancy outcomes. The data were collected from the 2012 Healthcare Cost and Utilization Project Nationwide Inpatient Sample (HCUP-NIS). Pregnancies in obese women with a prior bariatric surgery were compared to those of obese women without. Outcomes of interest were pre-eclampsia, IUGR, intrauterine fetal demise, large for gestational age, postpartum hemorrhage, failed induction of labor, cesarean delivery and operative vaginal delivery. Multivariable logistic regression analysis was used to adjust for potential confounders.

Results: 186?605 obese women with singleton gestations were identified. Among these, 1585 (0.8%) women had a prior bariatric surgery. Prior bariatric surgery was associated with an increased risk of IUGR (5.7% versus 2.2%, adjusted odds ratio 2.89, 99% CI 1.55–5.39, p?<?0.0001) even after adjusting for confounding factors. No differences were seen in our other outcomes of interest.

Conclusion: Singleton gestations in obese women with a prior bariatric surgery have an increased risk of IUGR. It may be reasonable screen these pregnancies for the development of growth restriction.     

Headache and adverse pregnancy outcomes: a prospective study

Objective

To investigate the association between headache, namely migraine and tension-type headache, and adverse pregnancy outcome.

Study design

Prospective cohort study conducted in three tertiary care centres in Italy: 376 pregnant women suffering from headache and 326 non-headache pregnant women as controls were recruited. The diagnosis of headache was made at the beginning of pregnancy, according to the criteria of the International Classification of Headache Disorders (ICHD-II). Women were followed up until delivery, and gestational age at delivery, mode of delivery, indications for operative delivery or caesarean section, birth weight, and centile of neonatal weight at birth were carefully recorded. Main outcome measures of the study were: preterm delivery, newborns small for gestational age, and foetal losses. Odds ratios and 95% confidence intervals were calculated.

Results

The incidence of preterm delivery (Adj OR, 95% CI 2.74, 1.27–5.91) was significantly higher in women suffering from headache than in controls. There was no statistically significant difference in small for gestational age newborns between the groups. Fewer women in the headache group had preterm elective caesarean section or induction of labour, than did controls, indicating a higher chance of spontaneous preterm delivery. Multivariate analysis showed that the association between headache, either migraine or tension-type, and adverse perinatal outcomes was statistically significant regardless of pre-eclampsia.

Conclusions

Women with headache should be considered at risk for adverse perinatal outcomes and should, therefore, be included in a high-risk pregnancy protocol of care throughout pregnancy.     

Epigenetic dysregulation of Insulin-like growth factor (IGF)-related genes and adverse pregnancy outcomes: a systematic review

Objectives: Preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA) are leading causes of neonatal mortality and morbidity around the world. Epigenetic alterations of the human genome may be involved in the causal chain of adverse pregnancy outcomes. In this systematic review we investigated whether PTB, LBW and SGA are associated with epigenetic dysregulation of insulin-like growth factor-related genes (IGF).

Methods: We searched MEDLINE and EMBASE for peer-reviewed articles about IGF and PTB, LBW and SGA published up to February 2015. Two independent reviewers selected original, controlled, human studies published in any language and graded them using the Newcastle–Ottawa Quality Assessment Scale. Disagreements were resolved by consensus with a third reviewer.

Results: Eighteen observational studies of low-to-moderate quality met the eligibility criteria out of 210 unique studies. There was substantial heterogeneity across studies. Most studies reported no, limited or borderline association between epigenetic changes (methylation or imprinting) of IGF-related genes and LBW or SGA. There were no IGF-related epigenetic studies of PTB.

Conclusions: Overall, evidence of an association between epigenetic abnormalities of IGF-related genes and LBW or SGA was weak and inconsistent. Methodological concerns limited results validity.     

Women with endometriosis at first pregnancy have an increased risk of adverse obstetric outcome

Objective: To evaluate pregnancy, delivery and neonatal outcome in singleton primiparous versus multiparous women with/without endometriosis.

Methods: Multicentric, observational and cohort study on a group of Caucasian pregnant women (n?=?2239) interviewed during their hospitalization for delivery in five Italian Gynecologic and Obstetric Units (Siena, Rome, Padua, Varese and Florence).

Results: Primiparous women with endometriosis (n?=?219) showed significantly higher risk of small for gestational age fetuses (OR: 2.72, 95% CI 1.46–5.06), gestational diabetes (OR: 2.13, 95% CI 1.32–3.44), preterm premature rupture of membranes (OR: 2.93, 95% CI 1.24–6.87) and preterm birth (OR: 2.24, 95% CI 1.46–3.44), and were hospitalized for a longer period of time (p?n?=?1331). Multiparous women with endometriosis (n?=?97) delivered significantly more often small for gestational age fetuses (OR: 2.93, 95% CI 1.28–6.67) than control group (n?=?592). Newborns of primiparous women with endometriosis needed more frequently intensive care (p?=?0.05) and were hospitalized for a longer period of time (p?Conclusions: Women with endometriosis at first pregnancy have an increased risk of impaired obstetric outcome, while a reduced number of complications occur in the successive gestation. Therefore, it is worthy for obstetricians to increase the surveillance in nulliparous women with endometriosis during pregnancy.     

Racial discrimination and the black-white gap in adverse birth outcomes: a review

Introduction: The purpose of this integrative review was to evaluate what is known about the relationship between racial discrimination and adverse birth outcomes. Methods: A search of the Cumulative Index of Nursing and Allied Health Literature, MEDLINE, and PsycINFO was conducted. The keywords used were: preterm birth, premature birth, preterm delivery, preterm labor, low birth weight, very low birth weight, racism, racial discrimination, and prejudice. Ten research studies were reviewed. All of the studies included African American women in their samples, were conducted in the United States, and were written in English. We did not limit the year of publication for the studies. Data were extracted based on the birth outcomes of preterm birth, low birth weight, or very low birth weight. Results: A consistent positive relationship existed between perceptions of racial discrimination and preterm birth, low birth weight, and very low birth weight. No relationship was found between racial discrimination and gestational age at birth. Discussion: Future research should explore the effects of racial discrimination as a chronic stressor contributing to the persistent gap in birth outcomes between racial groups.     

Update on the birth weight standard and its diagnostic value in small for gestational age (SGA) infants in China

Objectives: To identify the difference between the current newborn birth weight standard and the previous standard in China, and to evaluate the diagnostic value of newborn birth weight in small for gestational age (SGA) infants.

Methods: A retrospective analysis was conducted of 112?441 delivery cases in 2011, from 39 hospitals at different levels in 14 provinces and autonomous regions. Cases with incomplete data, gestational age?<24 weeks, or severe fetal malformations or fetal death were excluded. Data were recorded and entered on hard paper copies and into an online database. SPSS 18.0 and SAS 9.2 statistical software were used for data analysis.

Results: This study included 109?004 valid cases with an average birth weight of 3226.02?±?525.82?g. Birth weight changed significantly from 1988 for all gestational ages. In preterm infants with gestational age?<37 weeks, birth weight for each gestational week was lower than that in the birth weight standard from 15 cities in China in 1988 (p?+6 weeks showed significantly higher average birth weights compared with the previous birth weight standards (p?Conclusions: The current birth weight standard used in Chinese medical institutions was enacted in 1988. This is not suitable for today’s socioeconomic and clinical requirements, and needs to be updated. Diagnosis of preterm infants with SGA based upon the updated demographic birth weight standard manifested higher accuracy and avoided unnecessary medical interventions. However, the updated demographic birth weight standards were no better diagnostically than the previous standard for full-term infants. Customized birth weight standards from larger sample sizes and multi-center studies will be necessary to determine the appropriate birth weight standards in developing countries.     

Birth weight centiles,risk of intrapartum compromise,and adverse perinatal outcomes in term infants

Objective: The objective of this study is to evaluate the association between birth weight centiles and the risk of intrapartum compromise and adverse neonatal outcomes in term pregnancies.

Methods: Retrospective study of 32?468 term singleton births at a major tertiary maternity hospital in Australia. Data comprised gestation, mode, and indication for delivery and adverse perinatal outcomes. Fetal sex and gestational age-specific birth weight centiles were the main exposure variable.

Results: Neonates?<21st birth weight centile had an increased risk of intrapartum compromise, the highest risk was in babies?<3rd centile (OR 4.04, 95% CI 3.34–4.89). The risk of adverse perinatal outcomes was increased in neonates?<21st and?>91st birth weight centiles. The highest risk was in those?<3rd centile (OR 2.35, 95% CI 2.00–2.75).

Conclusions: Fetal size measurements near term may be used as part of screening test for identifying fetuses at an increased risk of intrapartum compromise and adverse perinatal outcomes.     

Ethnicity and birth outcome: New Zealand trends 1980-2001: Part 2. Pregnancy outcomes for Maori women

BACKGROUND: While traditionally Maori perinatal mortality has been similar to that of other ethnic groups, rates of preterm birth, small for gestational age (SGA) and teenage pregnancy have remained high. AIMS: To review current trends in preterm birth, SGA and teenage pregnancy for Maori during 1980-2001 and to highlight the major factors that have influenced Maori reproductive outcomes during this period. METHODS: De-identified birth registration data from 1 189 120 singleton live births and 5775 stillbirths were analysed for 1980-2001. Outcomes of interest included preterm birth, SGA and late fetal death while explanatory variables included maternal ethnicity, age and NZ Deprivation Index decile. Trend analysis was undertaken for 1980-1994 and multivariate logistic regression was used to explore risk factors for 1996-2001. RESULTS: During 1980-1994, Maori women had the highest preterm birth rates of any ethnic group in New Zealand, but in relative terms, inequalities declined as a consequence of a non-significant 7% fall in rates being offset by a statistically significant 30% increase for the European/other ethnic group. Rates of SGA were also higher amongst Maori women but declined by 25% during the 1980-1994 period. In addition, Maori women experienced significant socioeconomic gradients in SGA, with risk for Maori women in the most deprived NZDep areas being double that of Maori living affluent areas. Paradoxically, while Maori women had high rates of teenage pregnancy, this did not confer additional risk for preterm birth or SGA during the 1996-2001 period. CONCLUSIONS: While high rates of teenage pregnancy amongst Maori women appear not to confer additional risk for preterm birth or SGA, the social consequences of early childbearing may well be significant. The persistence of elevated rates of preterm birth and large socioeconomic gradients in SGA amongst Maori suggest that broader social and policy interventions are necessary if Maori are to achieve optimal birth outcomes in the coming decades.     

Ethnicity and birth outcome: New Zealand trends 1980-2001: Part 4. Pregnancy outcomes for European/other women

BACKGROUND: In the early 1980s European/other women made up 80% of New Zealand's population and experienced rates of preterm birth that were lower than for other ethnic groups. Rates of small for gestational age (SGA) and late fetal death were intermediate between those of Maori and Pacific women. AIMS: To examine trends in preterm birth, SGA and late fetal death for European/other women during 1980-2001 and to explore risk factors which make this group vulnerable to adverse birth outcome. METHODS: De-identified birth registration data from 1 189 120 singleton live births and 5775 stillbirths were analysed for 1980-2001. Outcomes of interest included preterm birth, SGA and late fetal death while explanatory variables included maternal ethnicity, age and NZ Deprivation Index decile. Trend analysis was undertaken for 1980-1994 and multivariate logistic regression was used to explore risk factors for 1996-2001. RESULTS: During 1980-1994, rates of preterm birth rose by 30% for European/other women, in contrast to a non-significant decline of 7% for Maori women and 4% for Pacific women. Rates of SGA declined 19% for European/other women, compared to 25% for Maori and 30% for Pacific women. Preterm birth and SGA were positively associated with teenage pregnancy and increasing NZDep deprivation. During 1980-1994, rates of late fetal death declined by 49%, with declines being similar for all ethnic groups. CONCLUSIONS: The progressive rise in preterm birth during the past two decades is a cause of concern for European/other women, particularly as it appears confined to this ethnic group. While rates of SGA have declined, albeit at a slower rate than for other ethnic groups, the elevated risk amongst teenagers and those living in the more deprived NZDep areas suggests that greater gains are achievable if interventions are targeted towards these particular groups.     

Ethnicity and birth outcome: New Zealand trends 1980-2001: Part 3. Pregnancy outcomes for Pacific women

BACKGROUND: Pacific women in New Zealand reside in areas of higher socioeconomic deprivation compared to women from other ethnic groups. Pacific women and their health are further disadvantaged because of genetic predisposition and sociocultural factors that cause ill-health. The correlations between pregnancy outcomes, risk factors and other health indices in Pacific women need evaluation. AIMS: To examine trends in preterm birth, small for gestational age (SGA) and late fetal death for Pacific women during 1980-2001 and to explore risk factors which make this group vulnerable to adverse birth outcome. METHODS: De-identified birth registration data from 1 189 120 singleton live births and 5775 stillbirths were analysed for 1980-2001. Outcomes of interest included preterm birth, SGA and late fetal death while explanatory variables included maternal ethnicity, age and NZ Deprivation Index decile. Trend analysis was undertaken for 1980-1994 and multivariate logistic regression was used to explore risk factors for 1996-2001. RESULTS: Pacific women had the lowest rates of preterm birth and SGA when compared to Maori and European women. In addition, preterm birth rates underwent a non-significant 4% decline and SGA rates a 30% decline during 1980-1994. Although there has been a 49% decline in late fetal deaths during 1980-1994, the rate remained higher for Pacific women than for Maori and European/other women. CONCLUSIONS: Despite residing in areas of high socioeconomic deprivation, which is associated with poor pregnancy outcomes for Maori and European/other women, Pacific women had better pregnancy outcomes, with lower preterm and SGA rates. The significant decline in rates of late fetal death during the past two decades is a cause for celebration; however, the rate remains higher for Pacific women than for other ethnic groups. Biological, cultural and social factors might explain the better pregnancy outcomes for Pacific women and these factors should be considered when developing future prevention programmes.     

Vigorous exercise and birth outcomes in a sample of recreational exercisers: a prospective study across pregnancy

OBJECTIVE: This study examined the question of whether vigorous exercise undertaken by recreational exercisers across pregnancy, defined in two ways, were associated with reduced infant birthweight and gestational age at birth. METHODS: A prospective approach was implemented. A total of 148 pregnant women participated. Average intensity duration and frequency of vigorous exercise reported were examined and compared with two existing definitions of vigorous exercise. Participants completed questionnaires (including retrospective reports on 3 months prepregnancy) and an exercise diary at 16-23 weeks pregnancy, 24-31 weeks pregnancy and 32-38 weeks pregnancy, and at 7 to 14 days post-partum a birth outcomes questionnaire was completed. RESULTS: There were no significant differences between exercise groups for birthweight and gestational age at birth. CONCLUSIONS: There was no evidence that the intensity duration and frequency of vigorous exercise were associated with significant reductions in mean birth outcomes for the infants of women who participated in the study. Replication in a large, more diverse sample is recommended.     

Maternal periodontal disease and adverse perinatal outcomes: is there an association? A hospital-based case-control study

Objectives: The association between maternal periodontal disease and adverse perinatal outcomes although extensively studied remains unclear. The aim of this study was to evaluate, by a case-control study, conducted in three hospitals the association between preterm birth and/or low birth weight (PTB/LBW) and clinical parameters of maternal periodontal disease.

Material and methods: Postpartum women who gave birth to a newborn PTB/LBW (case group), and postpartum women who had babies at full term with normal weight (control group) were included, in 1:2 ratio. Data were collected through medical records, interview, and periodontal clinical parameters. Bivariate analysis was performed to assess the PTB/LBW proportion relative to independent variables and multiple logistic regression analysis to assess the association between adverse perinatal outcomes and independent variables.

Results: The sample consisted of 148 cases and 296 controls. By the 148 postpartum women with PTB/LBW in case group, 126 (87.5%) had preterm birth, and 75 (50.7%) had PTB and LBW. The periodontal status and generalized periodontitis presence were not associated with any adverse pregnancy outcomes. Having made four or more prenatal visits was a protective factor for all outcomes. The history of previous PTB/LBW was a risk factor for new cases of PTB and PTB and/or LBW. The presence of systemic disease was associated with preterm and low birth weight (PTLBW). Preeclampsia and cesarean delivery were associated with all outcomes.

Conclusions: The clinical parameters of maternal periodontitis were not considered as a risk factor for the studied adverse perinatal outcomes.

Clinical relevance: The present study demonstrated no association between maternal periodontitis and PTB/LBW.     

Periodontal disease and adverse pregnancy outcomes: a systematic review

BACKGROUND: Recent studies suggest that periodontal disease, as a source of subclinical and persistent infection, may induce systemic inflammatory responses that increase the risk of adverse pregnancy outcomes. OBJECTIVES: To examine the existing evidence on the relationship between periodontal disease and adverse pregnancy outcomes. SEARCH STRATEGY: Published studies identified via searches of the MEDLINE, EMBASE, CINAHL, and Current Contents full-text databases. SELECTION CRITERIA: We identified and selected observational studies (i.e. case-control, cross-sectional, and cohort) and nonrandomised controlled studies or randomised controlled trials that examined periodontal disease as a risk factor for adverse pregnancy outcomes. DATA COLLECTION AND ANALYSIS: Odds ratios (OR) or risk ratios (RR) were extracted or calculated from the studies' data. We calculated pooled effect size for two clinical controlled trials but not for the observational studies due to the heterogeneity in definitions for periodontal disease and adverse pregnancy outcomes across studies. MAIN RESULTS: Twenty-five studies (13 case-control, 9 cohort, and 3 controlled trials) were identified. The studies focused on preterm low birthweight, low birthweight, preterm birth, birthweight by gestational age, miscarriage or pregnancy loss, and pre-eclampsia. Of the chosen studies, 18 suggested an association between periodontal disease and increased risk of adverse pregnancy outcome (ORs ranging from 1.10 to 20.0) and 7 found no evidence of an association (ORs ranging from 0.78 to 2.54). Three clinical trial studies suggest that oral prophylaxis and periodontal treatment can lead to a 57% reduction in preterm low birthweight (pooled RR 0.43; 95% CI 0.24-0.78) and a 50% reduction in preterm births (RR 0.5; 95% CI 0.20-1.30). AUTHOR'S CONCLUSIONS: Periodontal disease may be associated with an increased risk of adverse pregnancy outcome. However, more methodologically rigorous studies are needed for confirmation.     

A 12-year cohort study on adverse pregnancy outcomes in Eastern Townships of Canada: impact of endometriosis

The aim of this study was to provide a temporal-spatial reference of adverse pregnancy outcomes (APO) and examine whether endometriosis promotes APO in the same population. Among the 31?068 women who had a pregnancy between 1997 and 2008 in Eastern Townships of Canada, 6749 (21.7%) had APO. These APO increased significantly with maternal age and over time (r^2?=?0.522, p?=?0.008); and were dominated by preterm birth (9.3%), pregnancy-induced hypertension (8.3%) including gestational hypertension (6.5%), low birth weight (6.3%), gestational diabetes (3.4%), pregnancy loss (2.2%) including spontaneous abortion (1.5%) and stillbirth (0.6%), intrauterine growth restriction (2.1%) and preeclampsia (1.8%). Among the 31?068 pregnancies, 784 (2.5%) had endometriosis and 183 (23.3%) had both endometriosis and APO. Endometriosis has been shown to increase the incidence of fetal loss (OR?=?2.03; 95% CI?=?1.42–2.90, p?p?=?0.005) and stillbirth (OR?=?2.29; 95% CI?=?1.24–5.22, p?=?0.012). This study provides a temporal-spatial reference on APO, which is a valuable tool for monitoring, comparing and correcting. It is also the first study to highlight an impact of endometriosis on the incidence of spontaneous abortion and stillbirth.