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Low birth weight (LBW) and preterm birth (PTB) are primary factors contributing to morbidity and mortality among children aged under 5, resulting in a range of short- and long-term health consequences worldwide. Among the various risk factors, ambient air pollution poses a significant environmental risk and is a key determinant of child health. The prevalence of LBW and PTB among under 5 children sampled from the NFHS-5, 2019–2021, was combined with monthly PM2.5 data (2013–2021) obtained from the Atmospheric Composition Analysis Group at Washington University. Multivariable logistic regression models were used, and a stratified analysis was applied to understand the potential effect modifiers in LBW and PTB. Further, the geographical variation of LBW and PTB spatial autocorrelation (Moran’s I) was used. Geographically weighted regression and ordinary least square spatial regression were used to identify the spatial heterogeneity associated with selected variables. The study comprises a total of 208,181 under 5 children. Out of these children, the LBW rate was 17.41%, and the rate of PTB was 12.42%. The in-utero exposure to the mean concentration of PM2.5 was 56.01 μg/m3. The odds of suffering from LBW showed a non-linear shift when PM2.5 levels rose from the first octile (<28.02 μg/m3) to the last octile (>93.84 μg/m3) (adjusted odds ratio (AOR): 1.06, 95% CI: 1.01–1.12). While comparing the first octile of exposure to PM2.5 (>93.84 μg/m3) to the last octile, there was a 52% more likelihood of having PTB (AOR: 1.52, 95% CI: 1.43–1.61) after accounting for all relevant factors. These findings highlight the urgent need for a thorough strategy to control the air quality in India. Further, to reduce adverse birth outcomes, longitudinal studies and other co-pollutants can consider assessing the possible mechanisms mediating the relationship between maternal exposure and ambient air pollution.
Intimate partner violence is common amongst pregnant patients. It is associated with late entry to prenatal care, increased rates of preterm birth, depression, PTSD, and substance use during pregnancy. The USPTF supports screening of reproductive age individuals and ACOG supports the screening of all pregnant people. Screening is recommended at the beginning of pregnancy, during each trimester, and in the postpartum period to ensure those affected can be referred to resources for support. There are many validated screening tools but it is most important that patients are screened in private and they know their responses are confidential. Healthcare workers play an important role in helping to detect intimate partner violence and providing a safe healing environment for patients affected by intimate partner violence.
Cervical insufficiency is defined as the inability of the uterine cervix to retain a pregnancy, resulting in the subsequent delivery of the pregnancy in the absence of signs and symptoms consistent with labor, placental abruption, or both during the second trimester. It can be diagnosed based on obstetrical history, where painless cervical dilation in the second trimester led to pregnancy loss, or through physical examination findings in a current singleton pregnancy, revealing advanced painless cervical dilation. Treatment methods primarily rely on cervical cerclage placement using either transvaginal or transabdominal approaches. A cerclage may also be indicated to reduce the risk of preterm birth in a current singleton gestation with a shortened cervical length of under 25 mm, especially in the context of a history of preterm delivery before 34 weeks of gestation. The use of vaginal progesterone alone for the treatment of cervical insufficiency has not demonstrated effectiveness, although it might be beneficial in patients with singleton pregnancies and an incidentally found shortened cervical length.
Preterm labor, marked by cervical changes between 20 0/7 and 36 6/7 weeks’ gestation, is a significant contributor to preterm birth, accounting for 50% of such cases and is associated with increased neonatal mortality and long-term health issues. Understanding preterm labor involves considering diverse factors, including maternal medical history, demographics, and current pregnancy characteristics. Modifiable risk factors such as short interpregnancy intervals and substance use play a role in its onset. Diagnostic tools like transvaginal ultrasonography and fetal fibronectin aid in identifying at-risk individuals. Effective management of preterm labor is a pivotal aspect of obstetric care. Tocolytics, antenatal corticosteroids, and group B streptococcus prophylaxis are integral interventions. Decisions about the mode of delivery include the potential benefits of cesarean delivery in extreme prematurity. This case underscores the importance of vigilant monitoring, timely diagnosis, and intervention in addressing preterm labor, thereby mitigating its adverse effects on maternal and neonatal health.
Antenatal steroids (ANS) are one of the most widely prescribed medications in pregnancy, being administered to women at risk of preterm delivery. In the setting of preterm delivery at or below 35 weeks’ gestation, systematic review data show ANS reduce perinatal morbidity and mortality, primarily by promoting fetal lung maturation. However, with the expanding use of this intervention has come a growing appreciation for the potential off-target, adverse effects of ANS therapy on wider fetal development. We undertook a narrative literature review of the animal and clinical literature to assess current evidence for adverse effects of ANS exposure and fetal development. This review presents a summary of the evidence relating to the potential for wide-ranging, off-target, adverse effects of ANS therapy on fetal development and programming. We highlight an urgent need for further animal and clinical studies investigating the effects of ANS on the fetal immune, cardiovascular, renal and hepatic systems given a current sparsity of evidence. We also strongly suggest an emphasis on open disclosure, discussion and education of clinicians and patients with regard to the potential benefits and risks of ANS therapy, particularly in late preterm and term gestations where infants derive relatively few benefits from these drugs. We also propose further studies on the optimisation of ANS therapy through improved patient selection and improved dosing regimens based on a pharmacokinetic-pharmacodynamic informed understanding of ANS action on the fetal lung.
Spontaneous preterm birth remains the leading cause of neonatal death, and the second leading cause of mortality worldwide in children below five years of age. The causes of preterm birth are multifactorial, likely contributing to why significant progress in reducing the incidence has been slow. This Element contains the most up-to-date evidence regarding the aetiology, epidemiology, and management of pregnancies at risk of, or complicated by, spontaneous preterm birth and preterm pre-labour rupture of membranes. It concentrates largely on those aspects potentially amenable to preventative intervention (i.e. cervical dysfunction and premature uterine contractility), as well as strategies to improve outcomes for infants born prematurely.
Most women with epilepsy (WWE) will experience stable seizure control during pregnancy. Adverse fetal outcomes with epilepsy include spontaneous abortion, preterm birth, fetal growth restriction, major congenital malformation (MCM), hypertensive disorders of pregnancy, postpartum hemorrhage, peripartum depression, and—rarely—maternal death. Studies reporting these increased risks may be biased by differences in preexisting medical conditions, other patient characteristics, and anti-seizure medication (ASM) use and type. Poor seizure control preceding pregnancy, unplanned pregnancy, and polytherapy are associated with higher risks. Antenatal care should be coordinated by an experienced multidisciplinary team. Monotherapy with an appropriate ASM at the lowest effective dose is the goal, and drug levels should be monitored. Second trimester fetal anatomical sonography is the best screening modality for neural tube defects and other MCMs. Serial third trimester fetal growth ultrasounds are recommended. WWE are likely to have an uncomplicated labour and delivery. Epilepsy is not an indication for induction of labour or caesarean delivery. The risk of intrapartum seizures is 2−3%, and intractable seizures necessitating urgent delivery are rare. Attention is needed to avoid dehydration, missed ASM doses, sleep deprivation, and pain during labour and postpartum. WWE should be screened and counselled regarding their heightened risk of peripartum depression.
Previous studies have indicated associations between maternal mental disorders and adverse birth outcomes; however, these studies mainly focus on certain types of mental disorders, rather than the whole spectrum.
Aims
We aimed to conduct a broad study examining all maternal mental disorder types and adverse neonatal outcomes which is needed to provide a more complete understanding of the associations.
Method
We included 1 132 757 liveborn singletons born between 1997 and 2015 in Denmark. We compared children of mothers with a past (>2 years prior to conception; n = 48 646), recent (2 years prior to conception and during pregnancy; n = 15 899) or persistent (both past and recent; n = 10 905) diagnosis of any mental disorder, with children of mothers with no mental disorder diagnosis before the index delivery (n = 1 057 307). We also considered different types of mental disorders. We calculated odds ratios and 95% CIs of low birthweight, preterm birth, small for gestational age, low Apgar score, Caesarean delivery and neonatal death.
Results
Odds ratios for children exposed to past, recent and persistent maternal mental disorders suggested an increased risk for almost all adverse neonatal outcomes. Estimates were highest for children in the ‘persistent’ group for all outcomes, with the exception of the association between persistent maternal mental disorders and neonatal death (odds ratio 0.96, 0.62–1.48).
Conclusions
Our study provides evidence for increased risk of multiple adverse neonatal outcomes among children of mothers with mental disorders, highlighting the need for close monitoring and support for women with mental disorders.
Our aim was to estimate associations of adolescent dietary patterns and meal habits with hypertensive disorders of pregnancy (HDP) and preterm birth. We used data from a prospective cohort study (Norwegian Young-HUNT1) where dietary information was collected during adolescence and pregnancy outcomes were obtained through record linkage to the Norwegian national birth registry. The outcomes were HDP, hypertension, pre-eclampsia/eclampsia, and preterm birth in the first pregnancy and in any pregnancy. Diet was self-reported from validated questionnaires, and exposures were dietary indexes (healthy; unhealthy; fruit and vegetable; fibre index) and meal habits. Recruitment took place in schools. Eligible participants were females aged 13–19 years at the time of dietary assessment with a subsequent singleton pregnancy (n 3622). Women who reported a higher fibre intake in adolescence had a lower risk of pre-eclampsia in the first pregnancy (Relative Risk: 0·84; 95 % CI 0·7, 1·0), although this was weaker in sensitivity analyses. Regular meal habits in mid-adolescence (aged 13–15 years), particularly breakfast and lunch, were weakly associated with a lower risk of hypertension in pregnancy. Our results are the first to indicate an association between aspects of diet and dietary behaviour in mid-adolescence and subsequent HDP. More evidence is needed from larger studies to replicate the results and from alternative study designs to disentangle causality.
There are few data on long-term neurological or cognitive outcomes in the offspring of mothers with type 1 diabetes (T1D). The aims of this study were to examine if maternal T1D increases the risk of intellectual disability (ID) in the offspring, estimate the amount of mediation through preterm birth, and examine if the association was modified by maternal glycated hemoglobin (HbA1c).
Design
Population-based cohort study using population-based data from several national registries in Sweden.
Setting and participants
All offspring born alive in Sweden between the years 1998 and 2015.
Main outcome measure
The risk of ID was estimated through hazard ratios with 95% confidence intervals (HR, 95% CI) from Cox proportional hazard models, adjusting for potential confounding. Risks were also assessed in mediation analyses and in subgroups of term/preterm births, in relation to maternal HbA1c and by severity of ID.
Results
In total, 1,406,441 offspring were included. In this cohort, 7,794 (0.57%) offspring were born to mothers with T1D. The risk of ID was increased in offspring of mothers with T1D (HR; 1.77, 1.43–2.20), of which 47% (95% CI: 34–100) was mediated through preterm birth. The HRs were not modified by HbA1c.
Conclusion
T1D in pregnancy is associated with moderately increased risks of ID in the offspring. The risk is largely mediated by preterm birth, in particular for moderate/severe cases of ID. There was no support for risk-modification by maternal HbA1c.
Few studies have evaluated the joint effect of trace elements on spontaneous preterm birth (SPTB). This study aimed to examine the relationships between the individual or mixed maternal serum concentrations of Fe, Cu, Zn, Se, Sr and Mo during pregnancy, and risk of SPTB. Inductively coupled plasma MS was employed to determine maternal serum concentrations of the six trace elements in 192 cases with SPTB and 282 controls with full-term delivery. Multivariate logistic regression, weighted quantile sum regression (WQSR) and Bayesian kernel machine regression (BKMR) were used to evaluate the individual and joint effects of trace elements on SPTB. The median concentrations of Sr and Mo were significantly higher in controls than in SPTB group (P < 0·05). In multivariate logistic regression analysis, compared with the lowest quartile levels of individual trace elements, the third- and fourth-quartile Sr or Mo concentrations were significantly associated with reduced risk of SPTB with adjusted OR (aOR) of 0·432 (95 CI < 0·05). In multivariate logistic regression analysis, compared with the lowest quartile levels of individual trace elements, the third- and fourth-quartile Sr or Mo concentrations were significantly associated with reduced risk of SPTB with adjusted aOR of 0·432 (95 % CI 0·247, 0·756), 0·386 (95 % CI 0·213, 0·701), 0·512 (95 % CI 0·297, 0·883) and 0·559 (95 % CI 0·321, 0·972), respectively. WQSR revealed the inverse combined effect of the trace elements mixture on SPTB (aOR = 0·368, 95 % CI 0·228, 0·593). BKMR analysis confirmed the overall mixture of the trace elements was inversely associated with the risk of SPTB, and the independent effect of Sr and Mo was significant. Our findings suggest that the risk of SPTB decreased with concentrations of the six trace elements, with Sr and Mo being the major contributors.
An individual’s birthweight, a marker of in utero exposures, was recently associated with certain psychiatric conditions. However, studies investigating the relationship between an individual’s preterm birth status and/or birthweight and risk for depression during adulthood are sparse; we used data from the Women’s Health Initiative (WHI) to investigate these potential associations. At study entry, 86,925 postmenopausal women reported their birthweight by category (<6 lbs., 6–7 lbs. 15 oz., 8–9 lbs. 15 oz., or ≥10 lbs.) and their preterm birth status (full-term or ≥4 weeks premature). Women also completed the Burnham screen for depression and were asked to self-report if: (a) they had ever been diagnosed with depression, or (b) if they were taking antidepressant medications. Linear and logistic regression models were used to estimate unadjusted and adjusted effect estimates. Compared to those born weighing between 6 and 7 lbs. 15 oz., individuals born weighing <6 lbs. (βadj = 0.007, P < 0.0001) and ≥10 lbs. (βadj = 0.006, P = 0.02) had significantly higher Burnam scores. Individuals born weighing <6 lbs. were also more likely to have depression (adjOR 1.21, 95% CI 1.11–1.31). Individuals born preterm were also more likely to have depression (adjOR 1.18, 95% CI 1.02–1.35); while attenuated, this association remained in analyses limited to only those reportedly born weighing <6 lbs. Our research supports the role of early life exposures on health risks across the life course. Individuals born at low or high birthweights and those born preterm may benefit from early evaluation and long-term follow-up for the prevention and treatment of mental health outcomes.
Emerging evidence suggests that preterm-born individuals (<37 weeks gestation) are at increased risk of developing chronic health conditions in adulthood. This study compared the prevalence, co-occurrence, and cumulative prevalence of three female predominant chronic health conditions – hypertension, rheumatoid arthritis [RA], and hypothyroidism – alone and concurrently. Of 82,514 U.S. women aged 50–79 years enrolled in the Women’s Health Initiative, 2,303 self-reported being born preterm. Logistic regression was used to analyze the prevalence of each condition at enrollment with birth status (preterm, full term). Multinomial logistic regression models analyzed the association between birth status and each condition alone and concurrently. Outcome variables using the 3 conditions were created to give 8 categories ranging from no disease, each condition alone, two-way combinations, to having all three conditions. The models adjusted for age, race/ethnicity, and sociodemographic, lifestyle, and other health-related risk factors. Women born preterm were significantly more likely to have any one or a combination of the selected conditions. In fully adjusted models for individual conditions, the adjusted odds ratios (aORs) were 1.14 (95% CI, 1.04, 1.26) for hypertension, 1.28 (1.12, 1.47) for RA, and 1.12 (1.01, 1.24) for hypothyroidism. Hypothyroidism and RA were the strongest coexisting conditions [aOR 1.69, 95% CI (1.14, 2.51)], followed by hypertension and RA [aOR 1.48, 95% CI (1.20, 1.82)]. The aOR for all three conditions was 1.69 (1.22, 2.35). Perinatal history is pertinent across the life course. Preventive measures and early identification of risk factors and disease in preterm-born individuals are essential to mitigating adverse health outcomes in adulthood.
Preterm birth has been associated with insulin resistance and beta-cell dysfunction, a hallmark characteristic of type 2 diabetes. However, studies investigating the relationship between a personal history of being born preterm and type 2 diabetes are sparse. We sought to investigate the potential association between a personal history of being born preterm and risk for type 2 diabetes in a racially and ethnically diverse population. Baseline and incident data (>16 years of follow-up) from the Women’s Health Initiative (n = 85,356) were used to examine the association between personal history of being born preterm (born 1910–1940s) and prevalent (baseline enrollment; cross-sectional) or incident (prospective cohort) cases of type 2 diabetes. Logistic and Cox proportional hazards regression models were used to estimate odds and hazards ratios. Being born preterm was significantly, positively associated with odds for prevalent type 2 diabetes at enrollment (adjOR = 1.79, 95% CI 1.43–2.24; P < 0.0001). Stratified regression models suggested the positive associations at baseline were consistent across race and ethnicity groups. However, being born preterm was not significantly associated with risk for incident type 2 diabetes. Regression models stratified by age at enrollment suggest the relationship between being born preterm and type 2 diabetes persists only among younger age groups. Preterm birth was associated with higher risk of type 2 diabetes but only in those diagnosed with type 2 diabetes prior to study enrollment, suggesting the association between preterm birth and type 2 diabetes may exist at earlier age of diagnosis but wane over time.
Deficiency of essential trace element, Se, has been implicated in adverse birth outcomes and in child linear growth because of its important role in redox biology and associated antioxidant effects. We used data from a randomised controlled trial conducted among a cohort of pregnant and lactating women in Dhaka, Bangladesh to examine associations between Se biomarkers in whole blood (WBSe), serum and selenoprotein P (SEPP1) in maternal delivery and venous cord (VC) blood. Associations between Se biomarkers, birth weight and infant growth outcomes (age-adjusted length, weight, head circumference and weight-for-length z-scores) at birth, 1 and 2 years of age were examined using regression analyses. WB and serum Se were negatively associated with birth weight (adjusted β, 95 % CI, WBSe delivery: −26·6 (–44·3, −8·9); WBSe VC: −19·6 (–33·0, −6·1)); however, delivery SEPP1 levels (adjusted β: −37·5 (–73·0, −2·0)) and VC blood (adjusted β: 82·3 (30·0, 134·7)) showed inconsistent and opposite associations with birth weight. Positive associations for SEPP1 VC suggest preferential transfer from mother to fetus. We found small associations between infant growth and WBSe VC (length-for-age z-score β, 95 % CI, at birth: −0·05 (–0·1, −0·01)); 12 months (β: −0·05 (–0·08, −0·007)). Weight-for-age z-score also showed weak negative associations with delivery WBSe (at birth: −0·07 (–0·1, −0·02); 12 -months: −0·05 (–0·1, −0·005)) and in WBSe VC (at birth: −0·05 (–0·08, −0·02); 12 months: −0·05 (–0·09, −0·004)). Given the fine balance between essential nutritional and toxic properties of Se, it is possible that WB and serum Se may negatively impact growth outcomes, both in utero and postpartum.
The aim of the current study was to examine whether self-control skills in childhood moderate the association between very preterm birth (<32 weeks of gestational age) and emotional problems and peer victimization in adolescence. We used data from four prospective cohort studies, which included 29,378 participants in total (N = 645 very preterm; N = 28,733 full-term). Self-control was mother-reported in childhood at 5–11 years whereas emotional problems and peer victimization were both self- and mother-reported at 12–17 years of age. Findings of individual participant data meta-analysis showed that self-control skills in childhood do not moderate the association between very preterm birth and adolescence emotional problems and peer victimization. It was shown that higher self-control skills in childhood predict lower emotional problems and peer victimization in adolescence similarly in very preterm and full-term borns.
The USA has higher rates of preterm birth and incarceration than any other developed nation, with rates of both being highest in Southern states and among Black Americans, potentially due to rurality and socioeconomic factors. To test our hypothesis that prior-year county-level rates of jail admission, economic distress, and rurality were positively associated with premature birth rates in the county of delivery in 2019 and that the strength of these associations is greater for Black women than for White or Hispanic women, we merged five datasets to perform multivariable analysis of data from 766 counties across 12 Southern/rural states.
Methods:
We used multivariable linear regression to model the percentage of babies born premature, stratified by Black (Model 1), Hispanic (Model 2), and White (Model 3) mothers. Each model included all three independent variables of interest measured using data from the Vera Institute, Distressed Communities Index, and Index of Relative Rurality.
Results:
In fully fitted stratified models, economic distress was positively associated with premature births among Black (F = 33.81, p < 0.0001) and White (F = 26.50, p < 0.0001) mothers. Rurality was associated with premature births among White mothers (F = 20.02, p < 0.0001). Jail admission rate was not associated with premature births among any racial group, and none of the study variables were associated with premature births among Hispanic mothers.
Conclusions:
Understanding the connections between preterm birth and enduring structural inequities is a necessary scientific endeavor to advance to later translational stages in health-disparities research
While there is a physiological basis for the concern about preterm birth with sex in pregnancy, this risk has not been demonstrated in retrospective and prospective studies. In fact, in low-risk patients, sexual activity is typically associated with a decrease in preterm birth. In patients with a history of preterm birth, there is also no evidence that sexual activity increases the risk of preterm birth. Sexually transmitted infections (STIs) should be avoided in pregnancy due to the well-documented increased risk of preterm birth. Notably, sexual cohabitation for 12 months prior to conception (with maternal exposure to sperm) leads to a decrease in preeclampsia and likely to the risk of preterm birth.
Spontaneous preterm birth (PTB) refers to a delivery that occurs between weeks 20 and 37 of pregnancy, due to preterm labor, preterm prelabor rupture of membranes. and short cervical length at mid-trimester. The three most common risk factors for PTB are (1) prior history of preterm delivery, (2) twin pregnancy, and (3) short cervix at mid-trimester ultrasound. Several studies have demonstrated that short cervical length is the most powerful predictor for PTB in the index pregnancy for both singleton and twin pregnancies. A short cervical length means the measured length of the cervix is shorter than expected for the current gestational age, with a cutoff value between 20 and 25 mm. Sexual intercourse by itself has not been demonstrated to be a clear risk factor for PTB. Thus, abstinence after pregnancy has been achieved has no role in strategies for prevention of PTB. Also, most sexual positions and noncoital activities (e.g. oral sex, masturbation) during late pregnancy are not clearly associated with adverse pregnancy outcomes. There is no strong evidence that sexual activity affects the risk of PTB or onset of labor in healthy individuals. Pelvic rest may be recommended in selected cases, such as patients with a very short cervix or bulging membranes.
Arguably the most common cause of perinatal mortality and morbidity in multiple gestation is spontaneous preterm labour and delivery. A number of interventions have been evaluated in preventing spontaneous preterm birth in this this context, namely, bed rest (with or without hospitalization), oral tocolytics, home uterine activity monitoring, use of progesterone, cervical cerclage and cervical pessary. Most of the research is in this area relates to twin pregnancy with very little dedicated to triplet and higher order pregnancies. There are conflicting results but in the main, sadly, an effective primary preventative intervention remains elusive. This chapter will summarise what we know about the efficacy of the aforementioned interventions and highlight some specific scenarios where intervention may be beneficial.