Prenatal Exposure to Mercury, Manganese, and Lead and Adverse Birth Outcomes in Suriname: A Population-Based Birth Cohort Study

Globally, adverse birth outcomes are increasingly linked to prenatal exposure to environmental contaminants, such as mercury, manganese, and lead. This study aims to assess an association between prenatal exposure to mercury, manganese, and lead and the occurrence of adverse birth outcomes in 380 pregnant women in Suriname. The numbers of stillbirths, preterm births, low birth weights, and low Apgar scores were determined, as well as blood levels of mercury, manganese, lead, and relevant covariates. Descriptive statistics were calculated using frequency distributions. The associations between mercury, manganese, and lead blood levels, on the one hand, and adverse birth outcomes, on the other hand, were explored using contingency tables, tested with the χ²-test (Fisher's exact test), and expressed with a p value. Multivariate logistic regression models were computed to explore independent associations and expressed as (adjusted) odds ratios (aOR) with 95% confidence intervals (CI). The findings of this study indicate no statistically significant relationship between blood mercury, manganese, or lead levels and stillbirth, preterm birth, low birth weight, and low Apgar score. However, the covariate diabetes mellitus (aOR 5.58, 95% CI (1.38-22.53)) was independently associated with preterm birth and the covariate hypertension (aOR 2.72, 95% CI (1.081-6.86)) with low birth weight. Nevertheless, the observed high proportions of pregnant women with blood levels of mercury, manganese, and lead above the reference levels values of public health concern warrants environmental health research on risk factors for adverse birth outcomes to develop public health policy interventions to protect pregnant Surinamese women and their newborns from potential long-term effects.

Association between hypertensive medication during pregnancy and risk of several maternal and neonatal outcomes in women with chronic hypertension: a population-based study

BACKGROUND

Several studies have reported an association between perinatal complications and the severity of the hypertensive disease. The increasing number of pregnancies complicated by hypertension and the small assurance about the perinatal effects of hypertensive drug use during pregnancy involves the need of studying the better management of hypertensive mothers.

OBJECTIVE

To evaluate the association between maternal use of antihypertensive drugs and maternal and neonatal outcomes in women with chronic hypertension.

STUDY DESIGN

We conducted a population-based study including all deliveries of hypertensive women that occurred between 2007-2017 in the Lombardy region, Italy. We evaluated the risk of several maternal and neonatal outcomes among women who filled antihypertensive prescriptions within the 20th week of gestation. Propensity score stratification was used to account for key potential confounders.

RESULTS

Out of 5,553 pregnancies, 2,138 were exposed to antihypertensive treatment. With respect to no-users, users of antihypertensive drugs showed an increased risk of preeclampsia (RR:1.68, 95%CI:1.42-1.99), low birth weight (1.30,1.14-1.48), and preterm birth (1.25,1.11-1.42). These results were consistent in a range of sensitivity and subgroup analyses.

CONCLUSION

Early exposure to antihypertensive drugs in the first 20 weeks of gestation was associated with an increased risk of preeclampsia, low birth weight, and preterm birth.

Use of Antibiotic Treatment in Pregnancy and the Risk of Several Neonatal Outcomes: A Population-Based Study

BACKGROUND

Limited evidence is available on the safety and efficacy of antimicrobials during pregnancy, with even less according to the trimester of their use.

OBJECTIVE

This study aimed to evaluate the association between exposure to antibiotics therapy (AT) during pregnancy and short-term neonatal outcomes.

METHODS

We considered 773,237 deliveries that occurred between 2007-2017 in the Lombardy region of Italy. We evaluated the risk of neonatal outcomes among infants that were born to mothers who underwent AT during pregnancy. The odds ratios and the hazard ratios, with the 95% confidence intervals, were estimated respectively for early (first/second trimester) and late (third trimester) exposure. The propensity score was used to account for potential confounders. We also performed subgroup analysis for the class of AT.

RESULTS

We identified 132,024 and 76,921 singletons that were exposed to AT during early and late pregnancy, respectively. Infants born to mothers with early exposure had 17, 11, and 16% increased risk of preterm birth, low birth weight, and low Apgar score, respectively. Infants that were exposed in late pregnancy had 25, 11, and 13% increased risk of preterm birth, low birth weight, and low Apgar score, respectively. The results were consistent in the subgroup analysis.

CONCLUSION

Our results suggested an increased risk of several neonatal outcomes in women exposed to ATs during pregnancy, albeit we were not able to assess to what extent the observed effects were due to the infection itself. To reduce the risk of neonatal outcomes, women that are prescribed AT during pregnancy should be closely monitored.

Combining Resampling Strategies and Ensemble Machine Learning Methods to Enhance Prediction of Neonates with a Low Apgar Score After Induction of Labor in Northern Tanzania

Objective

The goal of this study was to establish the most efficient boosting method in predicting neonatal low Apgar scores following labor induction intervention and to assess whether resampling strategies would improve the predictive performance of the selected boosting algorithms.

Methods

A total of 7716 singleton births delivered from 2000 to 2015 were analyzed. Cesarean deliveries following labor induction, deliveries with abnormal presentation, and deliveries with missing Apgar score or delivery mode information were excluded. We examined the effect of resampling approaches or data preprocessing on predicting low Apgar scores, specifically the synthetic minority oversampling technique (SMOTE), borderline-SMOTE, and the random undersampling (RUS) technique. Sensitivity, specificity, precision, area under receiver operating curve (AUROC), F-score, positive predicted values (PPV), negative predicted values (NPV) and accuracy of the three (3) boosting-based ensemble methods were used to evaluate their discriminative ability. The ensemble learning models tested include adoptive boosting (AdaBoost), gradient boosting (GB) and extreme gradient boosting method (XGBoost).

Results

The prevalence of low (<7) Apgar scores was 9.5% (n = 733). The prediction models performed nearly similar in their baseline mode. Following the application of resampling techniques, borderline-SMOTE significantly improved the predictive performance of all the boosting-based ensemble methods under observation in terms of sensitivity, F1-score, AUROC and PPV.

Conclusion

Policymakers, healthcare informaticians and neonatologists should consider implementing data preprocessing strategies when predicting a neonatal outcome with imbalanced data to enhance efficiency. The process may be more effective when borderline-SMOTE technique is deployed on the selected ensemble classifiers. However, future research may focus on testing additional resampling techniques, performing feature engineering, variable selection and optimizing further the ensemble learning hyperparameters.

Adverse neonatal outcomes associated with pregestational diabetes mellitus in infants born preterm

BACKGROUND

Pregestational diabetes mellitus is associated with a higher risk of adverse pregnancy outcomes. Based on the available data, it is unclear whether infants born preterm to mothers with pregestational diabetes mellitus are at a higher risk of adverse outcomes than other preterm infants.

OBJECTIVE

This study aimed to quantify the neonatal complications associated with pregestational diabetes mellitus in infants born preterm.

STUDY DESIGN

This was a retrospective cohort study of all nonanomalous singleton neonates born in Texas from 2006 to 2014. Analysis was limited to births between 24 and 36 weeks' gestation and excluded multiple births, stillbirths, fetal congenital anomalies, neonates born to mothers with gestational diabetes mellitus, and neonates born to mothers with chronic hypertension. Results were stratified by pregestational diabetes mellitus status. Neonatal outcomes of interest included infant death, neonatal intensive care unit admission, low 5-minute Apgar scores, assisted ventilation of >6 hours, surfactant administration, and seizures. Multivariate logistic regression analysis was performed to estimate the association between pregestational diabetes mellitus and neonatal outcomes controlling for potential confounding variables.

RESULTS

After predefined exclusions, 277,210 births were analyzed, 4164 of which were to mothers with pregestational diabetes mellitus. The comparison group consisted of mothers without pregestational diabetes mellitus. The preterm infant mortality rates between the pregestational diabetic and nondiabetic groups were similar. However, after adjusting for confounding variables, there was an increased risk of infant mortality for preterm neonates born to mothers with pregestational diabetes mellitus. In infants born preterm, pregestational diabetes mellitus was associated with an increased risk of infant death, low 5-minute Apgar score, prolonged assisted ventilation, surfactant requirement, and neonatal intensive care unit admission. Neonates born before 34 weeks' gestation had an increased risk of assisted ventilation of >6 hours, neonatal intensive care unit admission, and seizure. Neonates born to mothers with pregestational diabetes mellitus in the late preterm period between 34 and 36 weeks' gestation had an increased risk of low Apgar score at 5 minutes, assisted ventilation of >6 hours, surfactant use, and neonatal intensive care unit admission.

CONCLUSION

Pregestational diabetes mellitus is associated with a higher risk of adverse neonatal outcomes in infants born preterm.

Impact of maternal HIV infection on pregnancy outcomes in southwestern China - a hospital registry based study

Globally, human immune deficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) continues to be a major public health issue. With improved survival, the number of people living with HIV/AIDS is increasing, with over 2 million among pregnant women. Investigating adverse pregnant outcomes of HIV-infected population and associated factors are of great importance to maternal and infant health. A cross-sectional data collected from hospital delivery records of 4397 mother-infant pairs in southwestern China were analysed. Adverse pregnant outcomes (including low birthweight/preterm delivery/low Apgar score) and maternal HIV status and other characteristics were measured. Two hundred thirteen (4.9%) mothers were HIV positive; maternal HIV infection, rural residence and pregnancy history were associated with all three indicators of adverse pregnancy outcomes. This research suggested that maternal population have high prevalence in HIV infection in this region. HIV-infected women had higher risks of experiencing adverse pregnancy outcomes. Rural residence predisposes adverse pregnancy outcomes. Findings of this study suggest social and medical support for maternal-infant care needed in this region, selectively towards rural areas and HIV-positive mothers.

Probiotics decrease the stress response and intestinal permeability of term neonates with low Apgar scores

To observe the effect of probiotics on the stress responses and intestinal permeability of term neonates with low Apgar scores, the present study retrospectively analyzed the clinical data of 78 term neonates (42 males and 36 females). In the control group (n=38), total parenteral nutrition and comprehensive treatment (anti-infection therapy) were provided. In the observation group (n=40), the neonates were administered Lactobacillus Complex Capsules in addition to the control group treatment. The corticotropin-releasing factor level was determined using ELISA; cortisol levels were determined using a radioimmunoprecipitation assay; D-lactate and diamine oxidase levels were determined using ultraviolet spectrometry; procalcitonin levels were determined using ECL; and C-reactive protein levels were determined using a protein analyzer. Following treatment, the levels of all parameters were lower in the observation group compared with the control group, and the differences were statistically significant (P<0.05). In the observation group, the daily milk intake was 16.57±2.58 ml, which was significantly higher than that of the control group (13.26±1.87 ml), while the length of hospital stay and total parenteral nutrition time, which were 12.31±2.02 and 6.21±1.26 days, respectively, in the observation group, were significantly shorter than those of the control group (14.86±2.58 and 8.86±1.78 days, respectively), and the differences were statistically significant (P<0.001). The results of the present study suggested that probiotics can ameliorate the stress response and intestinal permeability of term neonates with low Apgar scores, thereby, facilitating gastrointestinal function recovery.

Impact of recommended changes in labor management for prevention of the primary cesarean delivery

BACKGROUND

The dramatic rise in cesarean delivery rates worldwide in recent decades, without evidence of a concomitant decrease in cerebral palsy rates, has raised concerns about its potential negative consequences for maternal and infant health. In 2014, the American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine jointly published an Obstetric Care Consensus for safe prevention of the primary cesarean delivery.

OBJECTIVE

We sought to assess whether modification of our protocol to implement these recommendations helped to decrease our primary cesarean delivery rate safely.

STUDY DESIGN

This is a before-and-after retrospective cohort study at a university referral hospital. In March 2014, the threshold for defining active labor changed from 4 to >6 cm and arrest of first-stage labor from lack of cervical change despite regular contractions after 3 hours of oxytocin administration with amniotomy and epidural anesthesia to no change after 4 hours of adequate or 6 hours of inadequate contractions in women with an epidural. The definition of second-stage arrest of labor changed simultaneously from lack of progress for 3 hours with adequate contractions in women with epidural anesthesia to no progress for ≥4 hours in nulliparas or 3 hours in multiparas with an epidural. We compared maternal and neonatal outcomes over two 1 year periods: from March 2013 to February 2014 (before, preguideline) and from June 2014 to May 2015 (after, postguideline). We included all women with singleton pregnancies at ≥37 weeks' gestation, in vertex presentation, in spontaneous or induced labor, and with epidural anesthesia. We excluded women with an elective or previous cesarean delivery and those with obstetric or fetal complications.

RESULTS

This study included 3283 and 3068 women in the before and after periods, respectively. The groups had similar general and obstetric characteristics. The global cesarean delivery rate decreased significantly from 9.4% in the preguideline to 6.9% in the postguideline period (odds ratio, 0.71; 95% confidence interval, 0.59-0.85; P < .01). The cesarean delivery rate for arrest of first-stage labor fell by half, from 1.8% to 0.9% (odds ratio, 0.51; 95% confidence interval, 0.31-0.81; P < .01) but was significant only among nulliparous women. The cesarean delivery rate for second-stage arrest of labor decreased but not significantly between periods (1.3% vs 1.0%; odds ratio, 0.73; 95% confidence interval, 0.44-1.22; P = .2), and the cesarean delivery rate for failure of induction remained similar (3.7% vs 3.5%; odds ratio, 1.06; 95% confidence interval, 0.06-13.24; P = .88). The median duration of labor before cesarean delivery also became significantly longer among nulliparous women during the later period. Maternal and neonatal outcomes did not differ between the 2 periods, except that the rate of 1 minute Apgar score <7 fell significantly in the later period (8.4% vs 6.9%; odds ratio, 0.80; 95% confidence interval, 0.66-0.97; P = .02).

CONCLUSION

The modification of our protocol by implementing the new consensus recommendations was associated with a reduction of the rate of primary cesarean delivery performed for arrest of labor with no apparent increase in immediate adverse neonatal outcomes in nulliparous women at term with singleton pregnancies in vertex presentation and with epidural anesthesia. Further studies are needed to assess the long-term maternal and neonatal safety of these policies.

Thyroid autoimmunity in pregnancy and its influences on maternal and fetal outcome in Iran (a prospective study)

AIM OF THE STUDY

Thyroid dysfunction and autoimmunity are common problems in women of child-bearing age. It could be associated with pregnancy morbidities in the mother and fetus. Due to lack of sufficient data about the prevalence of thyroid autoimmunity in pregnant women in Iran, and controversies about its complications on pregnancy outcomes, this study was conducted.

MATERIALS AND METHODS

This is a prospective study on 600 singleton pregnant women in 15-28 weeks of pregnancy; they were residents of Fars province. We evaluated the prevalence of preeclampsia, intra-uterine growth retardation (IUGR), preterm delivery and low Apgar score and their association with TSH, thyroid peroxidase (TPO), and thyroglobulin (Tg) antibodies.

RESULTS

Prevalence of anti-TPO and anti-Tg positivity is 12.8% and 8.5% among Iranian pregnant women. Mothers with either positive TPO or Tg antibody have a higher risk of preeclampsia (p = 0.019), preterm delivery (p < 0.001), IUGR (p < 0.001), and low first minute Apgar score (p < 0.001). This association was independent of thyroid dysfunction for preterm delivery (RR = 5, p < 0.001), and low Apgar score neonates (RR = 8.8, p < 0.001), but this association for preeclampsia was due to thyroid dysfunction (RR = 3.7, p = 0.003). About IUGR in either TPO or Tg positive mothers, this association results from the additive effect of thyroid dysfunction and thyroid autoimmunity (RR = 8.3, p < 0.001). Cesarean section delivery was significantly higher in abnormal TSH/positive anti-Tg mothers (p = 0.045).

CONCLUSION

Thyroid autoimmunity independent of thyroid dysfunction could have significant adverse outcomes in the mother and fetus. Further investigation should be done to reveal the significance of screening and treating the thyroid autoimmunity during pregnancy.

Recurrence risk of low Apgar score among term singletons: a population-based cohort study

OBJECTIVE

To examine the risk of recurrence of low Apgar score in a subsequent term singleton pregnancy.

DESIGN

Population-based cohort study.

SETTING

The Netherlands.

POPULATION

A total of 190,725 women with two subsequent singleton term live births between 1999 and 2007.

METHODS

We calculated the recurrence risk of low Apgar score after adjustment for possible confounders. Women with an elective cesarean delivery, fetus in breech presentation or a fetus with congenital anomalies were excluded. Results were reported separately for women with a vaginal delivery or a cesarean delivery at first pregnancy.

MAIN OUTCOME MEASURES

Prevalence of birth asphyxia, a 5-min Apgar score <7.

RESULTS

The risk for an Apgar score of <7 in the first pregnancy was 0.99% and overall halved in the subsequent pregnancies (0.50%). For those with asphyxia in the first pregnancy, the risk of recurrence of a low Apgar score in the subsequent pregnancy was 1.1% (odds ratio 2.1, 95% confidence interval 1.4-3.3). This recurrence risk was present in women with a previous vaginal delivery (odds ratio 2.1, 95% confidence interval 1.2-3.5) and in women with a previous cesarean delivery (odds ratio 3.8, 95% confidence interval 1.7-8.5). Among women with a small-for-gestational-age infant in the subsequent pregnancy and a previous vaginal delivery, the recurrence risk was 4.8% (adjusted odds ratio 5.8, 95% confidence interval 2.0-16.5).

CONCLUSION

Women with birth asphyxia of the first born have twice the risk of renewed asphyxia at the next birth compared to women without birth asphyxia of the first born. This should be incorporated in the risk assessment of pregnant women.