Preterm delivery: a public health perspective

Optimizing the timing of antenatal corticosteroid administration prior to anticipated preterm birth: A retrospective cohort study

OBJECTIVE

To examine suboptimal antenatal corticosteroid (ACS) administration based on indications and maternal-obstetrical factors.

METHODS

Women who prematurely delivered (24 + 0 to 36 + 6 gestational weeks) a viable neonate following ACS treatment between 2012 and 2019 were identified by a retrospective database review. The cohort was divided into patients in whom ACS administration was optimally timed (≥24 h to ≤7 days) or suboptimally timed (>7 days). The groups were compared for ACS indications and maternal, obstetrical, and neonatal parameters.

RESULTS

The cohort included 399 women. ACS timing was optimal in 233 patients (58%) and was associated with nulliparity (109 [46.8%] vs. 54 [32.5%], P = 0.004) and preterm premature rupture of membranes (89 [38.2%] vs. 45 [27.1%], P = 0.021). Suboptimal timing was associated with chronic hypertension (22 [9.4%] vs. 36 [21.7%], P < 0.001) and asymptomatic cervical shortening (23 [9.9%] vs. 26 [15.7%], P = 0.020). Optimal ACS timing was associated with higher neonatal intensive care unit admission (135 [58%] vs. 71 [42.8%], P = 0.003). On multivariate analysis, the adjusted odds ratio (aOR) of neonatal intensive care unit admission was 0.69 (95% confidence interval [CI], 0.58-0.83, P < 0.001) and 0.99 (95% CI, 0.99-1, P = 0.003) when adjusted for gestational age and birth weight, respectively. When adjusting for maternal age, the aOR for suboptimal ACS administraion due to chronic hypertension was 2.65 (95% CI, 1.49-4.72; P < 0.001).

CONCLUSION

Optimal timing of ACS varies based on different maternal characteristics and clinical indications. In the presence of certain parameters physicians tend to administer ACS suboptimally, diminishing its beneficial effect.

Women's lived experiences of preterm birth and neonatal care for premature infants at a tertiary hospital in Ghana: A qualitative study

Preterm birth is a leading cause of death in children under five and a major public concern in Ghana. Women's lived experiences of care following preterm birth in clinical setting represents a viable adjunctive measure to improve the quality of care for premature infants. This qualitative study explored the knowledge and experiences of women who have had preterm birth and the associated challenges in caring for premature infants at a tertiary hospital. A qualitative design using in-depth interviews (IDIs) was conducted among women who experienced preterm birth with surviving infants at the Korle-Bu Teaching Hospital in Accra, Ghana. A thematic content analysis using the inductive analytic framework was undertaken using Nvivo. Thirty women participated in the study. We observed substantial variation in women's knowledge on preterm birth: some women demonstrated significant understanding of preterm delivery including its causes such as hypertension in pregnancy, and potential complications including neonatal death whilst others had limited knowledge on the condition. Women reported significant social and financial challenges associated with preterm birth that negatively impacted the quality of postnatal care they received. Admission of preterm infants at the neonatal intensive care unit (NICU) generated enormous psychological and emotional stress on the preterm mothers due to uncertainty associated with the prognosis of their babies, health system challenges and increased cost. Context-specific recommendations to improve the quality of care for prematurely born infants were provided by the affected mothers and include urgent need to expand the National Health Insurance Scheme (NHIS) coverage and more antenatal health education on preterm birth. Mothers of premature infants experienced varied unanticipated challenges during the care for their babies within the hospital setting. While knowledge of preterm birth seems adequate among women, there was a significant gap in the women's expectations of the challenges associated with the care of premature infants of which the majority experience psychosocial, economic and emotional impact.

Association between progesterone treatment and neonatal outcome in preterm births: a retrospective analysis

This retrospective study was conducted to determine if infants born prematurely despite prophylactic maternal progesterone treatment during pregnancy may still benefit from its adjunct properties and have decreased neonatal complications. 248 women treated with vaginal/intramuscular progesterone during pregnancy and 2519 controls who gave birth to a preterm newborn (24 + 0-36 + 6 gestational weeks) at a tertiary medical centre in 2012-2019. The primary outcome measure was neonatal infectious composite outcome. Secondary outcome measures were other maternal and neonatal complications. Compared to controls, the study group was characterised by lower gestational age at birth (35.0 ± 2.66 vs. 36.0 ± 2.23 weeks, p < .001), lower birth weight (2294 vs. 2485 g, p < .001), higher rates of neonatal infectious composite outcome (27.82 vs. 21.36%, p = 0.024), NICU admission, periventricular leukomalacia, and mechanical ventilation. The higher neonatal infectious composite outcome is likely associated with the lower gestational age at birth in this high-risk group and not the progesterone treatment per se.IMPACT STATEMENTWhat is already known on this subject? Several randomised controlled trials have shown that progesterone administration in pregnancy significantly reduced the rate and complications of preterm birth. A recent study reported that vaginal administration of progesterone during pregnancy was more effective than intramuscular administration in decreasing vaginal group B Streptococcus (GBS) colonisation. This finding raises the question of whether progesterone treatment may have additional benefits besides preventing preterm birth and may reduce neonatal complication rate in preterm infants.What do the results of this study add? This is the first study examining the impact of gestational progesterone exposure on outcomes of preterm infants. The primary objective was a composite measure of infectious neonatal outcomes. Newborns who had progesterone exposure on average had lower gestational age, lower birth weight and higher neonatal infectious composite outcome. The significant difference is explained by lower gestational age.What are the implications of these findings for clinical practice and/or further research? Progesterone is widely used to prevent preterm birth, and may have important additive effects even when prematurity is not avoided. Although the findings did not support our initial hypothesis, they warrant further examination with larger cohorts.

Critical analysis of electrohysterographic methods for continuous monitoring of intrauterine pressure

Monitoring the progression of uterine activity provides important prognostic information during pregnancy and delivery. Currently, uterine activity monitoring relies on direct or indirect mechanical measurements of intrauterine pressure (IUP), which are unsuitable for continuous long-term observation. The electrohysterogram (EHG) provides a non-invasive alternative to the existing methods and is suitable for long-term ambulatory use. Several published state-of-the-art methods for EHG-based IUP estimation are here discussed, analyzed, optimized, and compared. By means of parameter space exploration, key parameters of the methods are evaluated for their relevance and optimal values. We have optimized all methods towards higher IUP estimation accuracy and lower computational complexity. Their accuracy was compared with the gold standard accuracy of internally measured IUP. Their computational complexity was compared based on the required number of multiplications per second (MPS). Significant reductions in computational complexity have been obtained for all published algorithms, while improving IUP estimation accuracy. A correlation coefficient of 0.72 can be obtained using fewer than 120 MPS. We conclude that long-term ambulatory monitoring of uterine activity is possible using EHG-based methods. Furthermore, the choice of a base method for IUP estimation is less important than the correct selection of electrode positions, filter parameters, and postprocessing methods. The presented review of state-of-the-art methods and applied optimizations show that long-term ambulatory IUP monitoring is feasible using EHG measurements.

Toll-like receptor 4 contributes to uterine activation by upregulating pro-inflammatory cytokine and CAP expression via the NF-κB/P38MAPK signaling pathway during pregnancy

Evidence indicates that inflammatory response is significant during the physiological process of human parturition; however, the specific signaling pathway that triggers inflammation is undefined. Toll-like receptors (TLRs) are key upstream gatekeepers that control inflammatory activation before preterm delivery. Our previous study showed that TLR4 expression was significantly increased in human pregnancy tissue during preterm and term labor. Therefore, we explore whether TLR4 plays a role in term labor by initiating inflammatory responses, therefore promoting uterine activation. The results showed that expression of TLR4, interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), CC chemokine ligand 2 (CCL-2), and uterine contraction-associated proteins (CAPs) was upregulated in the human and mice term labor (TL) group compared with the not-in-labor (TNL) group, and the TLR4 level positively correlated with CAP expression. In pregnant TLR4-knockout (TLR4^-/- ) mice, gestation length was extended by 8 hr compared with the wild-type group, and the expression of IL-1β, IL-6, TNF-α, CCL-2, and CAPs was decreased in TLR4^-/- mice. Furthermore, nuclear factor-κB (NF-κB) and P38MAPK activation is involved in the initiation of labor but was inhibited in TLR4^-/- mice. In uterine smooth muscle cells, the expression of inflammatory cytokines and CAPs decreased when the NF-κB and P38MAPK pathway was inhibited. Our data suggest that TLR4 is a key factor in regulating the inflammatory response that drives uterine activation and delivery initiation via activating the NF-κB/P38MAPK pathway.

Dysbiosis and Prematurity: Is There a Role for Probiotics?

Healthy microbiota is a critical mediator in maintaining health and it is supposed that dysbiosis could have a role in the pathogenesis of a number of diseases. Evidence supports the hypothesis that maternal dysbiosis could act as a trigger for preterm birth; aberrant colonization of preterm infant gut might have a role in feeding intolerance and pathogenesis of necrotizing enterocolitis. Despite several clinical trials and meta-analyses, it is still not clear if modulation of maternal and neonatal microbiota with probiotic supplementation decreases the risk of preterm birth and its complications.

At the forefront of psychoneuroimmunology in pregnancy: Implications for racial disparities in birth outcomes PART 1: Behavioral risks factors

Birth prior to full term is a substantial public health issue. In the US, ˜400,000 babies per year are born preterm (<37 weeks), while>1 million are early term (37-38^6/7 weeks). Birth prior to full term confers risk both immediate and long term, including neonatal intensive care, decrements in school performance, and increased mortality risk from infancy through young adulthood. Risk for low birth weight and preterm birth are 1.5-2 times greater among African Americans versus Whites. Psychosocial stress related to being a member of a discriminated racial minority group contributes substantially to these racial disparities. Providing promising targets for intervention, depressed mood, anxiety, and poor sleep are each linked with exposure to chronic stress, including racial discrimination. A rigorous transdisciplinary approach addressing these gaps holds great promise for clinical impact in addressing racial disparities as well as ameliorating effects of stress on perinatal health more broadly. As will be reviewed in a companion paper, the mechanistic roles of physiological sequelae to stress - including neuroendocrine, inflammatory regulation, biological aging, and the microbiome - also require delineation.

Improved Quality of Life for Children With Beckwith-Wiedemann Syndrome Following Tongue Reduction Surgery

Macroglossia is observed in the majority of patients with Beckwith-Wiedemann syndrome (BWS), a congenital condition with characteristic anomalies. In addition, sleep disordered breathing (SDB) associated with macroglossia has occasionally been noted in BWS patients, for which tongue reduction surgery is generally performed. However, macroglossia is related to various health problems, such as eating and articulation disorders, attention deficit disorder, enuresis, and thorax deformation, as well as aesthetic issues. Therefore, in addition to treating airway obstruction, tongue reduction surgery can also exert favorable effects on the overall quality of life (QOL) of patients. However, surgical indications for tongue reduction have yet to be established and reports on QOL assessments after surgery are rare. The OSA-18 questionnaire is used for screening SDB and is also useful for assessing the effect of tongue reduction surgery on QOL. We report a patient whose QOL was improved by tongue reduction surgery. On the basis of our patient's results, we recommend tongue reduction surgery in early childhood not only to treat SDB but also to improve QOL.

Racial difference in preterm birth and low birthweight: Towards a new hypothesis involving the interaction of 25-hydroxyvitamin D with maternal fat mass

Preterm birth (PB) and low birthweight (LBW) remain a leading cause of infant mortality worldwide. Persistent racial disparities in prevalence rates have been reported, with the highest values observed in Subsaharan Africa and South Asia. In United States, non-Hispanic Black women are more likely to have a premature or low-birth-weight baby. Beyond the speculative debate on factors explaining such racial disparity, the key-question remains about the path from race to birth outcomes. Several hypotheses emerged from the published literature to explain the racial difference in likelihood for PB and LBW. However, the 'Hispanic paradox' remains unexplained. We relied here on published data to hypothesize that the racial disparity in PB/LBW is a consequence to the joint influence of 25-hydroxyvitamin D and fat mass. Beyond its role as a source of 1,25-dihydroxyvitamin D, the 25-hydroxyvitamin D is directly implicated in the fetal growth and the normal completion of pregnancy. Because of its lipophilic property, a large part of 25-hydroxyvitamin D is swiftly trapped into fat mass and the circulating fraction impact the body development during fetal period. We postulate that the positive effect of vitamin D to prevent PB/LBW is less beneficial for women with high fat mass, independent of race. The core problem may be related to bioavailable 25-hydroxyvitamin D, not directly to race.

Hypertriglyceridemia and adverse outcomes during pregnancy

Introducción. Durante el embarazo, los niveles séricos de triglicéridos maternos aumentan como un mecanismo de adaptación fisiológica para suplir las necesidades del feto en desarrollo. Pese a que el incremento excesivo se ha asociado a preeclampsia, macrosomía y parto pretérmino, no se han establecido de manera contundente los niveles a partir de los cuales se deben tomar medidas en cada trimestre para prevenir complicaciones.Objetivo. Hacer una revisión sobre fisiopatología, efectos en madre e hijo, valores esperados en cada trimestre e intervenciones terapéuticas en hipertrigliceridemia gestacional.Materiales y métodos. Se realizó una revisión con la búsqueda de artículos en las bases de datos ScienceDirect, PubMed, Scopus, LILACS, Cochrane y SciELO con los términos: Pregnancy; Hypertriglyceridemia; Maternal-Fetal Exchange; Fetal Development; Pregnancy Complications y sus equivalentes en español.Resultados. Se encontraron 59 artículos que cumplieron los criterios de búsqueda y daban respuesta a los objetivos.Conclusiones. El número limitado y la gran variabilidad de los datos indican la necesidad de realizar más investigaciones que establezcan los rangos de normalidad de los triglicéridos durante los tres trimestres del embarazo y así determinar riesgos e intervenciones eficaces antes de la gestación y reducir la morbimortalidad materno-infantil.

Financial strain and birth weight: the mediating role of psychological distress

The effects of financial strain during pregnancy have received limited attention. In addition, data examining the pathways by which SES indicators contribute to birth weight are lacking. The objective of the current study was to examine the potential pathway of psychological distress in the relationship between financial strain and birth weight. Participants consisted of 138 pregnant women who completed measures assessing financial strain, depressive symptoms, pregnancy-specific distress, perceived stress, and general anxiety during pregnancy (mean gestational age = 18.5, SD = 7.2). Birth outcome data were obtained via medical record review. Simple and parallel mediation models were conducted using PROCESS. Simple mediation models showed that depressive symptoms (95% CI -24.65, -0.90) and pregnancy-specific distress (95% CI -37.31, -5.91), but not perceived stress (95% CI -31.17, 4.69) or anxiety (95% CI -25.84, 5.57), served as mediators in the relationship between financial strain and birth weight. When depressive symptoms and pregnancy-specific distress were included in the same mediation model, only pregnancy-specific distress remained significant. Financial strain was positively associated with all facets of psychological distress and negatively associated with birth weight during pregnancy. The current study demonstrated the mechanistic role of pregnancy-specific distress in the link between financial strain and birth weight in a racially diverse sample. Interventions targeting pregnancy-specific distress may mitigate the effects of financial strain on birth weight. Studies examining whether pregnancy-specific distress accounts for the relationship between other types of stressor exposures and birth weight would be informative.

Maternal lipid profile and the relation with spontaneous preterm delivery: a systematic review

BACKGROUND

It is unknown whether an unfavorable (atherogenic) lipid profile and homocysteine level, which could supersede clinical cardiovascular disease, is also associated with an increased risk of spontaneous preterm delivery (sPTD). A systematic review of studies assessing the lipid profile and homocysteine value of women with sPTD compared to women with term delivery in pre-pregnancy and during pregnancy.

METHODS

A systematic search of peer-reviewed articles published between January 1980 and May 2014 was performed using MEDLINE, EMBASE and the Cochrane database. We included case-control and cohort studies that examined triglycerides, high/low density lipoprotein cholesterol, total cholesterol and homocysteine in women with sPTD. Articles were subdivided in pre-pregnancy, first, second and third trimester. Of 708 articles reviewed for eligibility, 14 met our inclusion criteria.

RESULTS AND CONCLUSION

Nine cohort studies and five case-control studies were analyzed, reporting on 1466 cases with sPTD and 11296 controls with term delivery. The studies suggest a possible elevated risk of sPTD in woman with high TG levels, no association of high and low density lipoprotein cholesterol with the risk of sPTD was found. High homocysteine levels are associated with sPTD in the second trimester. The role of triglycerides and homocysteine in sPTD should be explored further.

Novel Toll-like receptor-4 antagonist (+)-naloxone protects mice from inflammation-induced preterm birth

Toll-like receptor 4 (TLR4) activation by bacterial infection, or by sterile inflammatory insult is a primary trigger of spontaneous preterm birth. Here we utilize mouse models to investigate the efficacy of a novel small molecule TLR4 antagonist, (+)-naloxone, the non-opioid isomer of the opioid receptor antagonist (−)-naloxone, in infection-associated preterm birth. Treatment with (+)-naloxone prevented preterm delivery and alleviated fetal demise in utero elicited by i.p. LPS administration in late gestation. A similar effect with protection from preterm birth and perinatal death, and partial correction of reduced birth weight and postnatal mortality, was conferred by (+)-naloxone administration after intrauterine administration of heat-killed E. coli. Local induction by E. coli of inflammatory cytokine genes Il1b, Il6, Tnf and Il10 in fetal membranes was suppressed by (+)-naloxone, and cytokine expression in the placenta, and uterine myometrium and decidua, was also attenuated. These data demonstrate that inhibition of TLR4 signaling with the novel TLR4 antagonist (+)-naloxone can suppress the inflammatory cascade of preterm parturition, to prevent preterm birth and perinatal death. Further studies are warranted to investigate the utility of small molecule inhibition of TLR-driven inflammation as a component of strategies for fetal protection and delaying preterm birth in the clinical setting.

Maternal exposure to di-2-ethylhexylphthalate and adverse delivery outcomes: A systematic review

Adverse pregnancy outcomes, including preterm delivery, short gestational age, and abnormal birth weight, remain a public health concern. The evidence on the association of the most common phthalate, di-2-ethylhexyl phthalate (DEHP) with adverse pregnancy outcomes remains equivocal. This systematic review summarizes published studies that investigated the association of DEHP with preterm delivery, gestational age, and birthweight. A comprehensive literature search found 15 relevant studies, most of which evaluated more than one outcome (four studies for preterm delivery, nine studies for gestational age, and ten studies for birthweight). Studies varied greatly with respect to study design, exposure assessment, analytical methods, and direction of the associations. We identified important methodological concerns which could have resulted in selection bias and exposure misclassification and contributed to null findings and biased associations. Given limitations of the previous studies discussed in this review, more thorough investigation of these associations is warranted to advance our scientific knowledge.

Evaluation the effect of 17-alpha hydroxyprogesterone caproate on gestational diabetes mellitus in pregnant women at risk for preterm birth

BACKGROUND

The mellitus exact role of 17-alpha hydroxyprogesterone caproate in increasing the rate of gestational diabetes mellitus (GDM) is still unclear. This study was aimed to investigate the association of treatment with 17-alpha hydroxyprogesterone caproate with GDM in pregnant women who are at risk for preterm birth (PTB).

MATERIALS AND METHODS

In this clinical trial, 200 singleton pregnant women included 100 pregnant women at risk for PTB or with history of PTB as case group (received weekly injections of 17-alpha hydroxyprogesterone caproate) and 100 healthy pregnant women without history of PTB as control group (did not receive any drug) were evaluated. All women followed until detect or reject of GDM, and abnormal glucose challenge test (GCT) and GDM were calculated in all of them.

RESULTS

During study follow-up, 36 women in both groups were excluded and 81 cases 83 controls completed the study and analyzed. Mean of GCT in all studied pregnant women was 128.2 ± 18.1, whereas, in cases was higher than controls but no significant difference was noted between groups (P = 0.56). Abnormality in GCT was observed in 32 (19.5%) of 164 studied women, (18 of cases and 14 of controls), which was not statistically significant (P = 0.34). The frequency of GDM among all studied women was 7.9% (13 of 164), 7 of cases and 6 of controls, which was not significant (P = 0.74).

CONCLUSION

In summary, results demonstrated that weekly administration of 17-alpha hydroxyprogesterone caproate is not associated with higher rates of GDM in pregnant women at risk for PTB.

Toll-Like Receptor 4 Is an Essential Upstream Regulator of On-Time Parturition and Perinatal Viability in Mice

An inflammatory response is instrumental in the physiological process of parturition but the upstream signals initiating inflammation are undefined. Because endogenous ligands for Toll-like receptor 4 (TLR4) are released in late gestation, we hypothesized that on-time labor requires TLR4 signaling, to trigger a cytokine and leukocyte response and accelerate the parturition cascade. In pregnant TLR4-deficient (Tlr4-/-) mice, average gestation length was extended by 13 hours and increased perinatal mortality was seen compared with wild-type controls. Quantification of cytokine and uterine activation gene expression showed that late gestation induction of Il1b, Il6, Il12b, and Tnf expression seen in control placenta and fetal membranes was disrupted in Tlr4-/- mice, and accompanied by a transient delay in expression of uterine activation genes, including prostaglandin F receptor, oxytocin receptor, and connexin-43. Leukocyte populations were altered before birth in TLR4-deficient females, with fewer neutrophils and macrophages in the placenta, and fewer dendritic cells and more regulatory T cells in the myometrium. Administration of TLR4 ligand lipopolysaccharide to pregnant wild-type mice induced cytokine expression and fetal loss, whereas Tlr4-/- pregnancies were protected. The small molecule TLR4 antagonist (+)-naloxone increased mean duration of gestation by 16 hours in wild-type mice. Collectively, these data demonstrate that TLR4 is a key upstream regulator of the inflammatory response acting to drive uterine activation and control the timing of labor. Because causal pathways for term and preterm labor converge with TLR4, interventions to manipulate TLR4 signaling may have therapeutic utility for women at risk of preterm labor, or in postterm pregnancy.

Route of administration and formulation dependent pharmacokinetics of 17-hydroxyprogesterone caproate in rats

1. Weekly intramuscular injections of (250 mg/week) of 17-hydroxyprogesterone caproate (17-OHPC) are the only treatment option for prevention of preterm birth in women with a prior history of preterm delivery. 2. The objective of the current study was to evaluate the use of an alternate formulation and the feasibility of an alternate route of administration of this agent. 17-OHPC was administered to adult female SD rats, as marketed oily formulation intramuscularly, or as a solution IV, IM, or PO. 3. Plasma concentrations of 17-OHPC were measured by LC-MS-MS and pharmacokinetic parameters were calculated by non-compartmental analysis, using WinNonLin (Certara, St. Louis, MO). 4. After IV or IM administration as a solution, the mean half-life of 17-OHPC was around 11 h. The bioavailability was nearly 100% after IM administration, but was very low (<3%) after PO administration of a solution dosage form. 5. Intramuscular injection of the oily formulation resulted in low levels of 17-OHPC that were sustained for a prolonged time period with a projected bioavailability close to 100%. 6. The pharmacokinetics of 17-OHPC is dependent on the formulation and the route of administration. 7. The low bioavailability after oral administration indicates that oral administration of 17-OHPC may not be feasible with simple formulations of this drug.

Potential Peripartum Markers of Infectious-Inflammatory Complications in Spontaneous Preterm Birth

Spontaneous preterm birth significantly contributes to the overall neonatal morbidity associated with preterm deliveries. Nearly 50% of cases are associated with microbial invasion of the amniotic cavity followed by an inflammatory response. Robust diagnostic tools for neonates jeopardized by infection and inflammation may thus decrease the overall neonatal morbidity substantially. Amniotic fluid retrieved during labor retains fetal and pregnancy-related protein fingerprint and its sampling does not place any unwanted stress on women. Using exploratory and targeted methods we analyzed proteomes of amniotic fluid sampled at the end of spontaneous preterm labor prior to delivery from women with and without infection and inflammation. Exploratory data indicated several amniotic fluid proteins to be associated with infectious-inflammatory complications in spontaneous preterm birth. LC-SRM analysis subsequently verified statistically significant changes in lipocalin-1 (P = 0.047 and AUC = 0.67, P = 0.046), glycodelin (P = 0.013 and AUC = 0.73, P = 0.013), and nicotinamide phosphoribosyltransferase (P = 0.018 and AUC = 0.71, P = 0.01).

Associations between ozone and preterm birth in women who develop gestational diabetes

Prenatal exposure to ambient air pollutants might cause adverse birth outcomes; however, there have been few studies in which the association between air pollution and preterm birth was examined after stratifying by pregnancy complications. We conducted a population-based case-control study of 1,510,064 singleton births from the Taiwanese birth registry during 2001-2007. Of the total of 1,510,064 births, we designated all 86,224 preterm births as the case group and then randomly selected an additional 344,896 from the remaining births (equivalent to 4 full-term births for every 1 preterm birth) as the control sample. We used an inverse distance weighting approach to calculate an average exposure parameter for air pollutants. The adjusted odds ratio for preterm birth per 10-ppb increase in ozone was 1.12 (95% confidence interval: 1.01, 1.23) for women with gestational diabetes mellitus who were exposed in the third trimester and 1.02 (95% confidence interval: 1.01, 1.03) for women without gestational diabetes (P for interaction <0.001). These findings suggest that exposure to ozone in pregnancy is associated with an increased risk of preterm birth, particularly for women who have gestational diabetes mellitus.

Contextualizing racial disparities in preterm delivery: a rhetorical analysis of U.S. epidemiological research at the turn of the 21st century

Preterm delivery (PTD), defined as delivery prior to 37 weeks gestation, is a key contributor to persistent racial disparities in infant mortality in the United States. Five major funding initiatives were devoted to advancing PTD epidemiology during the 1990s and 2000s. By examining content and rhetorical features of 94 studies conducted under these initiatives, and published between 1993 and 2011, this paper considers how calls for more "contextual" approaches (focusing on social and environmental contexts) interacted with more "conventional" approaches (focusing on individual-level risk factors) to PTD epidemiology during this period. Contextual advocates initially emphasized complex biosocial reasoning to better connect social adversity with embodied outcomes. Yet responses by researchers invested in conventional approaches, as well as in studies published under new initiatives that explicitly claimed to incorporate contextual insights, often reframed this complex reasoning in biologically reductionist terms. Subsequent contextual advocates then focused on developing statistical methods to support research about social and environmental causes of PTD, and this strategy appears to have gained some traction with conventional researchers. These findings call for closer attention to language and power in both social scientific studies of epidemiological knowledge production, as well as among epidemiologists themselves.

The impact of social disadvantage on preconception health, illness, and well-being: an intersectional analysis

PURPOSE

To understand how social and structural contexts shape individual risk, vulnerability, and interconception health-related behaviors of African-American women. APPROACH OR DESIGN: A longitudinal ethnographic study was conducted.

SETTING

The study was conducted in Philadelphia, Pennsylvania.

PARTICIPANTS

The sample included 19 African-American women who were participants in the intervention group of a randomized clinical trial of interconceptional care.

METHOD

Data were collected through interaction with participants over a period of 6 to 12 months. Participant observation , structured and unstructured interviews, and Photovoice were used to obtain data; grounded theory was used for analysis. The analysis was guided by intersectional theory.

RESULTS

Social disadvantage influenced health and health care-seeking behaviors of African-American women, and the disadvantage centered on the experience of racism. The authors identify seven experiences grounded in the interactions among the forces of racism, class, gender, and history that may influence women's participation in and the effectiveness of preconception and interconception health care.

CONCLUSION

African-American women's health and wellness behaviors are influenced by an experience of racism structurally embedded and made more virulent by its intersection with class, gender, and history. These intersecting forces create what may be a unique exposure that contributes significantly to the proximal determinants of health inequities for African-American women. Health promotion approaches that focus on the individual as the locus of intervention must concomitantly unravel and address the intertwining structural forces that shape individual circumstance in order to improve women's interconceptional health and to reduce disparities.

Is a randomised controlled trial of a maternity care intervention for pregnant adolescents possible? An Australian feasibility study

Background

The way in which maternity care is provided affects perinatal outcomes for pregnant adolescents; including the likelihood of preterm birth. The study purpose was to assess the feasibility of recruiting pregnant adolescents into a randomised controlled trial, in order to inform the design of an adequately powered trial which could test the effect of caseload midwifery on preterm birth for pregnant adolescents.

Methods

We recruited pregnant adolescents into a feasibility study of a prospective, un-blinded, two-arm, randomised controlled trial of caseload midwifery compared to standard care. We recorded and analysed recruitment data in order to provide estimates to be used in the design of a larger study.

Results

The proportion of women aged 15–17 years who were eligible for the study was 34% (n=10), however the proportion who agreed to be randomised was only 11% (n = 1). Barriers to recruitment were restrictive eligibility criteria, unwillingness of hospital staff to assist with recruitment, and unwillingness of pregnant adolescents to have their choice of maternity carer removed through randomisation.

Conclusions

A randomised controlled trial of caseload midwifery care for pregnant adolescents would not be feasible in this setting without modifications to the research protocol. The recruitment plan should maximise opportunities for participation by increasing the upper age limit and enabling women to be recruited at a later gestation. Strategies to engage the support of hospital-employed staff are essential and would require substantial, and ongoing, work. A Zelen method of post-randomisation consent, monetary incentives and ‘peer recruiters’ could also be considered.

Azurocidin levels in maternal serum in the first trimester can predict preterm prelabor rupture of membranes

OBJECTIVE

To determine the possible association between azurocidin in maternal serum in the first trimester of pregnancy and subsequent spontaneous preterm labor, preterm prelabor rupture of membranes, and iatrogenic preterm delivery.

METHODS

Women who underwent first trimester screening for chromosomal abnormalities between January and November 2011 were included in the study, and a sample of maternal serum was obtained. In total, 1905 women were followed-up through the local record system, and 13 women with spontaneous preterm labor, 17 women with preterm prelabor rupture of membranes (PPROM), and 16 women with iatrogenic preterm delivery were identified. Twenty-two women with uncomplicated pregnancies who delivered at term were selected as controls. Maternal serum azurocidin levels in women were determined using ELISA.

RESULT

Women with PPROM had lower azurocidin levels (median 0.91 ng/mL, range 0.2-2.07) than women who delivered at term (median 1.63 ng/mL, range 0.4-10.98; p = 0.02). No differences in azurocidin levels between women with labor at term and those with either spontaneous preterm labor (median 1.46 ng/mL, range 0.19-2.59; p = 0.42) or iatrogenic preterm delivery (median 1.60 ng/mL, range 0.66-7.96; p = 0.27) were found.

CONCLUSIONS

Low levels of azurocidin in maternal serum in the first trimester were associated with subsequent PPROM.

Prenatal administration of progesterone for preventing preterm birth in women considered to be at risk of preterm birth

BACKGROUND

Preterm birth is a major complication of pregnancy associated with perinatal mortality and morbidity. Progesterone for the prevention of preterm labour has been advocated.

OBJECTIVES

To assess the benefits and harms of progesterone for the prevention of preterm birth for women considered to be at increased risk of preterm birth and their infants.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (14 January 2013) and reviewed the reference list of all articles.

SELECTION CRITERIA

Randomised controlled trials, in which progesterone was given for preventing preterm birth.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated trials for methodological quality and extracted data.

MAIN RESULTS

Thirty-six randomised controlled trials (8523 women and 12,515 infants) were included. Progesterone versus placebo for women with a past history of spontaneous preterm birth Progesterone was associated with a statistically significant reduction in the risk of perinatal mortality (six studies; 1453 women; risk ratio (RR) 0.50, 95% confidence interval (CI) 0.33 to 0.75), preterm birth less than 34 weeks (five studies; 602 women; average RR 0.31, 95% CI 0.14 to 0.69), infant birthweight less than 2500 g (four studies; 692 infants; RR 0.58, 95% CI 0.42 to 0.79), use of assisted ventilation (three studies; 633 women; RR 0.40, 95% CI 0.18 to 0.90), necrotising enterocolitis (three studies; 1170 women; RR 0.30, 95% CI 0.10 to 0.89), neonatal death (six studies; 1453 women; RR 0.45, 95% CI 0.27 to 0.76), admission to neonatal intensive care unit (three studies; 389 women; RR 0.24, 95% CI 0.14 to 0.40), preterm birth less than 37 weeks (10 studies; 1750 women; average RR 0.55, 95% CI 0.42 to 0.74) and a statistically significant increase in pregnancy prolongation in weeks (one study; 148 women; mean difference (MD) 4.47, 95% CI 2.15 to 6.79). No differential effects in terms of route of administration, time of commencing therapy and dose of progesterone were observed for the majority of outcomes examined. Progesterone versus placebo for women with a short cervix identified on ultrasound Progesterone was associated with a statistically significant reduction in the risk of preterm birth less than 34 weeks (two studies; 438 women; RR 0.64, 95% CI 0.45 to 0.90), preterm birth at less than 28 weeks' gestation (two studies; 1115 women; RR 0.59, 95% CI 0.37 to 0.93) and increased risk of urticaria in women when compared with placebo (one study; 654 women; RR 5.03, 95% CI 1.11 to 22.78). It was not possible to assess the effect of route of progesterone administration, gestational age at commencing therapy, or total cumulative dose of medication. Progesterone versus placebo for women with a multiple pregnancy Progesterone was associated with no statistically significant differences for the reported outcomes. Progesterone versus no treatment/placebo for women following presentation with threatened preterm labour Progesterone, was associated with a statistically significant reduction in the risk of infant birthweight less than 2500 g (one study; 70 infants; RR 0.52, 95% CI 0.28 to 0.98). Progesterone versus placebo for women with 'other' risk factors for preterm birth Progesterone, was associated with a statistically significant reduction in the risk of infant birthweight less than 2500 g (three studies; 482 infants; RR 0.48, 95% CI 0.25 to 0.91).

AUTHORS' CONCLUSIONS

The use of progesterone is associated with benefits in infant health following administration in women considered to be at increased risk of preterm birth due either to a prior preterm birth or where a short cervix has been identified on ultrasound examination. However, there is limited information available relating to longer-term infant and childhood outcomes, the assessment of which remains a priority.Further trials are required to assess the optimal timing, mode of administration and dose of administration of progesterone therapy when given to women considered to be at increased risk of early birth.

The consequences of chorioamnionitis: preterm birth and effects on development

Preterm birth is a major cause of perinatal mortality and long-term morbidity. Chorioamnionitis is a common cause of preterm birth. Clinical chorioamnionitis, characterised by maternal fever, leukocytosis, tachycardia, uterine tenderness, and preterm rupture of membranes, is less common than subclinical/histologic chorioamnionitis, which is asymptomatic and defined by inflammation of the chorion, amnion, and placenta. Chorioamnionitis is often associated with a fetal inflammatory response. The fetal inflammatory response syndrome (FIRS) is defined by increased systemic inflammatory cytokine concentrations, funisitis, and fetal vasculitis. Clinical and epidemiological studies have demonstrated that FIRS leads to poor cardiorespiratory, neurological, and renal outcomes. These observations are further supported by experimental studies that have improved our understanding of the mechanisms responsible for these outcomes. This paper outlines clinical and experimental studies that have improved our current understanding of the mechanisms responsible for chorioamnionitis-induced preterm birth and explores the cellular and physiological mechanisms underlying poor cardiorespiratory, neural, retinal, and renal outcomes observed in preterm infants exposed to chorioamnionitis.

Dietary supplementation with probiotics during late pregnancy: outcome on vaginal microbiota and cytokine secretion

Background

The vaginal microbiota of healthy women consists of a wide variety of anaerobic and aerobic bacterial genera and species dominated by the genus Lactobacillus. The activity of lactobacilli helps to maintain the natural healthy balance of the vaginal microbiota. This role is particularly important during pregnancy because vaginal dismicrobism is one of the most important mechanisms for preterm birth and perinatal complications. In the present study, we characterized the impact of a dietary supplementation with the probiotic VSL#3, a mixture of Lactobacillus, Bifidobacterium and Streptococcus strains, on the vaginal microbiota and immunological profiles of healthy women during late pregnancy.

Results

An association between the oral intake of the probiotic VSL#3 and changes in the composition of the vaginal microbiota of pregnant women was revealed by PCR-DGGE population profiling. Despite no significant changes were found in the amounts of the principal vaginal bacterial populations in women administered with VSL#3, qPCR results suggested a potential role of the probiotic product in counteracting the decrease of Bifidobacterium and the increase of Atopobium, that occurred in control women during late pregnancy. The modulation of the vaginal microbiota was associated with significant changes in some vaginal cytokines. In particular, the decrease of the anti-inflammatory cytokines IL-4 and IL-10 was observed only in control women but not in women supplemented with VSL#3. In addition, the probiotic consumption induced the decrease of the pro-inflammatory chemokine Eotaxin, suggesting a potential anti-inflammatory effect on the vaginal immunity.

Conclusion

Dietary supplementation with the probiotic VSL#3 during the last trimester of pregnancy was associated to a modulation of the vaginal microbiota and cytokine secretion, with potential implications in preventing preterm birth.

Trial registration

ClinicalTrials.gov NCT01367470

The role of 17 alpha-hydroxyprogesterone caproate in the prevention of preterm birth

Preterm birth is a major public-health problem in the USA, which has higher rates of preterm birth than most other developed countries. Attempts at the prevention of preterm birth have been largely unsuccessful. The recent publication of a large, multicenter, randomized trial of 17 alpha-hydroxyprogesterone caproate, which showed efficacy in preventing recurrent preterm delivery, has sparked renewed interest in progestational drugs in general and this compound in particular for use in preventing preterm delivery. Although this drug is not currently commercially available, an application has been made to the US FDA to produce 17 alpha-hydroxyprogesterone caproate, as Gestiva() for the prevention of preterm delivery.

O impacto do baixo peso ao nascer relacionado à depressão gestacional para o financiamento federal da saúde pública: uma análise do Município de Pelotas, Rio Grande do Sul, Brasil

O baixo peso ao nascer está relacionado com morbimortalidade e sequelas no desenvolvimento infantil, impactando nos custos dos sistemas de saúde, por isso é importante avaliar fatores que o influenciam, estimando seu impacto no Sistema Único de Saúde (SUS). Este é um estudo prospectivo aninhado a uma coorte de gestantes que realizaram pré-natal e parto exclusivamente pelo SUS nos hospitais com UTI da cidade de Pelotas, Rio Grande do Sul, Brasil. Entre os resultados, concluiu-se que mães com episódios de depressão gestacional apresentam quase quatro vezes mais chances de ter um filho com baixo peso ao nascer (RP = 3,94; IC: 1,49-10,36). Valendo-se do cálculo da fração atribuível na população, estima-se que, na população geral, 36,17% dos bebês com baixo peso ao nascer são filhos de mães que tiveram episódio depressivo, estimando-se um custo que pode chegar a mais de R$ 76 milhões no Brasil. Sugere-se que se ampliem as ações preventivas e curativas para as gestantes na área da saúde mental, possibilitando melhor desfecho de saúde dos recém-nascidos, e que se utilizem adequadamente os recursos do SUS.

Outcome of vaginal progesterone as a tocolytic agent: randomized clinical trial

Vaginal progesterone has a potential beneficial effect in postponing of preterm labor by suppression of prostaglandins cascades. Although different studies evaluated the use of progesterone for preterm birth, the exact effect of which on prolongation of pregnancy remains unclear. Seventy two women who underwent preterm labor were managed by magnesium sulfate. Then they were randomly assigned to continue pregnancy either by applying vaginal progesterone (400 mg) until delivery or without using any drug. Gestational age mean at the time of delivery (P = 0.039) and postponing delivery mean time (P = 0.048) were significantly higher in progesterone group. Comparison of neonatal outcomes between two groups of patients showed meaningful benefits of progesterone in increasing of neonatal weight, reduction of low birth weight babies, and lowing neonate admitted in NICU.

Use of progestogens in pregnant and infertile patients

Progesterone is an essential hormone in the occurence and maintenance of pregnancy. Natural or synthetic progestogens are commonly used in pregnant patients or patients undergoing infertility treatments for various indications. Most frequently put indications for the use of progestogens in these patient populations are the prevention of spontaneous preterm birth, the prevention of pregnancy loss in pregnancies with an unexplained recurrent pregnancy loss and in patients with threatened abortion. It is also used in pregnant women undergoing nonobstetric surgery, for infertility or recurrent pregnancy loss that is thought to be due to luteal phase defect or as a luteal support in stimulated IVF cycles. We aimed to review the current evidence for the use of progestogens in each of these settings.

Prevention of preterm birth

Preterm birth (delivery before 37 completed weeks of gestation) is common and rates are increasing. In the past, medical efforts focused on ameliorating the consequences of prematurity rather than preventing its occurrence. This approach resulted in improved neonatal outcomes, but it remains costly in terms of both the suffering of infants and their families and the economic burden on society. Increased understanding of the pathophysiology of preterm labor has altered the approach to this problem, with increased focus on preventive strategies. Primary prevention is a limited strategy which involves public education, smoking cessation, improved nutritional status and avoidance of late preterm births. Secondary prevention focuses on recurrent preterm birth which is the most recognisable risk factor. Widely accepted strategies include cervical cerclage, progesterone and dedicated clinics. However, more research is needed to explore the role of antibiotics and anti-inflammatory treatments in the prevention of this complex problem.

Psychoneuroimmunology in pregnancy: immune pathways linking stress with maternal health, adverse birth outcomes, and fetal development

It is well-established that psychological stress promotes immune dysregulation in nonpregnant humans and animals. Stress promotes inflammation, impairs antibody responses to vaccination, slows wound healing, and suppresses cell-mediated immune function. Importantly, the immune system changes substantially to support healthy pregnancy, with attenuation of inflammatory responses and impairment of cell-mediated immunity. This adaptation is postulated to protect the fetus from rejection by the maternal immune system. Thus, stress-induced immune dysregulation during pregnancy has unique implications for both maternal and fetal health, particularly preterm birth. However, very limited research has examined stress-immune relationships in pregnancy. The application of psychoneuroimmunology research models to the perinatal period holds great promise for elucidating biological pathways by which stress may affect adverse pregnancy outcomes, maternal health, and fetal development.

Role of African ancestry and gene-environment interactions in predicting preterm birth

OBJECTIVE

To estimate whether African ancestry, specific gene polymorphisms, and gene-environment interactions could account for some of the unexplained preterm birth variance within African American women.

METHODS

We genotyped 1,509 African ancestry-informative markers, cytochrome P450 1A1 (CYP1A1), and glutathione S-transferases Theta 1 (GSTT1) variants in 1,030 self-reported African American mothers. We estimated the African ancestral proportion using the ancestry-informative markers for all 1,030 self-reported African American mothers. We examined the effect of African ancestry and CYP1A1- and GSTT1-smoking interactions on preterm birth cases as a whole and within its subgroups: very preterm birth (gestational age less than 34 weeks); and late preterm birth (gestational age greater than 34 and less than 37 weeks). We applied logistic regression and receiver operating characteristic curve analysis, separately, to evaluate whether African ancestry and CYP1A1- and GSTT1-smoking interactions could make additional contributions to preterm birth beyond epidemiologic factors.

RESULTS

We found significant associations of African ancestry with preterm birth (22% compared with 31%, odds ratio [OR] 1.11, 95% confidence interval [CI] 1.02-1.20) and very preterm birth (23% compared with 33%, OR 1.17, 95% CI 1.03-1.33), but not with late preterm birth (22% compared with 29%, OR 1.06, 95% CI 0.97-1.16). In addition, the receiver operating characteristic curve analysis suggested that African ancestry and CYP1A1- and GSTT1-smoking interactions made substantial contributions to very preterm birth beyond epidemiologic factors.

CONCLUSION

Our data underscore the importance of simultaneously considering epidemiologic factors, African ancestry, specific gene polymorphisms, and gene-environment interactions to better understand preterm birth racial disparity and to improve our ability to predict preterm birth, especially very preterm birth.

Effect of pregestational maternal, obstetric and perinatal factors on neonatal outcome in extreme prematurity

PURPOSE

To investigate the effect of pregestational maternal, obstetric and perinatal factors on neonatal outcome in extreme preterm deliveries.

METHODS

Retrospective study of deliveries in a Norwegian tertiary teaching hospital. All women with live births at 24(+0)- 27(+6) weeks of gestation between 2004 and 2007 were included. Major morbidity is defined as intraventricular haemorrhage grade 3-4, periventricular leukomalacia, bronchopulmonary dysplasia or necrotizing enterocolitis. Pregestational maternal, obstetric and perinatal variables were initially compared for mortality and survival with major morbidity at 24-h, 7- or 28-day postpartum/discharge in univariate analysis. Then, a multivariate analysis was conducted in order to determine independent factors associated with mortality and survival with major morbidity.

RESULTS

A total of 109 babies were delivered alive in 92 women, representing 1.6% of total births. The survival rates were 93.6, 84.4 and 80.7%, with a prevalence of major morbidity among survivors of 40.4, 32.1 and 39.4% at 24-h, 7- and 30-day postpartum/discharge, respectively. After adjustment using multiple logistic regression, only a 5-min Apgar score ≤ 3 and babies with at least one major morbidity had significantly independent effects on neonatal survival. Multiple pregnancy and gestational age <26 weeks were the only two independent risk factors for survival with major morbidity.

CONCLUSIONS

Neonatal survival was significantly predicted by a 5-min Apgar score and neonatal morbidity, independent of pregestational maternal disease, obstetric complications, method of delivery, gestational age and birth weight in extreme preterm deliveries. The excess morbidity rate was confined among multiples and babies who were delivered before 26 weeks of gestation.

An integrated systems biology approach to the study of preterm birth using "-omic" technology--a guideline for research

Preterm birth is the leading cause of neonatal mortality and perinatal morbidity. The etiology of preterm is multi-factorial and still unclear. As evidence increases for a genetic contribution to PTB, so does the need to explore genomics, transcriptomics, proteomics and metabolomics in its study. This review suggests research guidelines for the conduct of high throughput systems biology investigations into preterm birth with the expectation that this will facilitate the sharing of samples and data internationally through consortia, generating the power needed to study preterm birth using integrated "-omics" technologies. The issues to be addressed include: (1) integrated "-omics" approaches, (2) phenotyping, (3) sample collection, (4) data management-integrative databases, (5) international consortia and (6) translational feasibility. This manuscript is the product of discussions initiated by the "-Omics" Working Group at the Preterm Birth International Collaborative Meeting held at the World Health Organization, Geneva, Switzerland in April 2009.

Father's education: an independent marker of risk for preterm birth

To explore the association between paternal education and preterm birth, taking into account maternal social and economic factors. We analyzed data from a population-based cross-sectional postpartum survey, linked with birth certificates, of women who gave birth in California from 1999 through 2005 (n = 21,712). Women whose infants' fathers had not completed college had significantly higher odds of preterm birth than women whose infants' fathers were college graduates, even after adjusting for maternal education and family income [OR (95% CI) = 1.26 (1.01-1.58)]. The effect of paternal education was greater among unmarried women than among married women. Paternal education may represent an important indicator of risk for preterm birth, reflecting social and/or economic factors not measured by maternal education or family income. Researchers and policy makers committed to understanding and reducing socioeconomic disparities in birth outcomes should consider paternal as well as maternal socioeconomic factors in their analyses and policy decisions.

Proportion of excision and cervical healing after large loop excision of the transformation zone for cervical intraepithelial neoplasia

OBJECTIVE

To determine how the proportion of the cervical volume excised affects cervical regeneration.

DESIGN

Prospective observational study.

SETTING

University Hospital.

POPULATION

Women planning to undergo excisional treatment for cervical intraepithelial neoplasia who wish to have future pregnancies.

METHODS

The cervical volume (and dimensions) is calculated with magnetic resonance imaging (MRI) before treatment. The volume (and dimensions) of the cone is assessed before fixation by a volumetric tube and a ruler; the percentage (%) of excision is computed. Cervical regeneration is estimated by repeat MRI at 6 months.

MAIN OUTCOME MEASURES

Cervical regeneration in relation to proportion of excision. Statistical analysis was performed by box plots and analysis of variance.

RESULTS

A total of 48 women have been recruited; 29 have completed 6 months follow up. Both the total cervical volume (from MRI) before treatment and the volume of the excised/ablated cone varied substantially. The estimated proportion of excision varied significantly between 4% and 39% (median 11%). Multivariate linear regression revealed that the proportional deficit at 6 months post-treatment was determined mainly by the proportion of the excised volume.

CONCLUSIONS

Careful assessment of risks and benefits of treatment is essential when deciding to treat women who wish to have future pregnancies. Assessment of the proportion of the cervical volume and length excised might identify those that need further surveillance during future pregnancy.

Lactobacillus rhamnosus GR-1 stimulates colony-stimulating factor 3 (granulocyte) (CSF3) output in placental trophoblast cells in a fetal sex-dependent manner

Bacterial vaginosis is associated with a 1.4-fold increased risk of preterm birth. We have shown previously that Lactobacillus rhamnosus GR-1 supernatant up-regulates interleukin 10 and down-regulates tumor necrosis factor-alpha output in lipopolysaccharide (LPS)-treated human primary placenta cultures in a fetal sex-dependent manner. We hypothesize that lactobacilli also exert their anti-inflammatory effect by up-regulation of colony-stimulating factor 3 (granulocyte) (CSF3), which is secreted from both immune and placental trophoblast cells, and that this activity is dependent on the sex of the fetus. Placental trophoblast cells were isolated from term elective cesarean section placentae using a Percoll gradient and separated from CD45(+) cells using magnetic purification. Cells were treated with LPS in the presence or absence of pretreatments with L. rhamnosus GR-1 supernatant or chemical inhibitors of the intracellular signaling pathways. Phosphorylations of mitogen-activated protein kinase 14 (MAPK14, previously known as p38) and signal transducer and activator of transcription (STAT) 3 were measured by Western blot analysis, and levels of CSF3 were determined by ELISA. CSF3 output was increased only in the placental trophoblast cells of female fetuses treated with LPS, GR-1 supernatant, and a combination of both treatments. The GR-1 supernatant up-regulated the phosphorylation of STAT3 and MAPK14. CSF3 output was inhibited by both Janus kinases (JAK) and MAPK14 inhibitors. None of the treatments was able to increase CSF3 output in either the pure trophoblast or the CD45(+) cell preparations alone. These results suggest an underlying mechanism for the sex difference in incidence of preterm birth and provide potential evidence for a therapeutic benefit of lactobacilli in reducing the risk of preterm labor.

The role of progesterone in prevention of preterm birth

Preterm birth continues to provide an enormous challenge in the delivery of perinatal health care, and is associated with considerable short and long-term health consequences for surviving infants. Progesterone has a role in maintaining pregnancy, by suppression of the calcium-calmodulin-myosin light chain kinase system. Additionally, progesterone has recognized anti-inflammatory properties, raising a possible link between inflammatory processes, alterations in progesterone receptor expression and the onset of preterm labor. Systematic reviews of randomized controlled trials evaluating the use of intramuscular and vaginal progesterone in women considered to be at increased risk of preterm birth have been published, with primary outcomes of perinatal death, preterm birth <34 weeks, and neurodevelopmental handicap in childhood. Eleven randomized controlled trials were included in the systematic review, involving 2714 women and 3452 infants, with results presented according to the reason women were considered to be at increased risk of preterm birth. While there is a potential beneficial effect in the use of progesterone for some women considered to be at increased risk of preterm birth, primarily in the reduction in the risk of preterm birth before 34 weeks gestation, it remains unclear if the observed prolongation of pregnancy translates into improved health outcomes for the infant.

Partner violence during pregnancy: prevalence, effects, screening, and management

The purpose of this review is to provide an overview of the current state of knowledge regarding the experience of intimate partner violence (IPV) during pregnancy. Pregnancy IPV is a significant problem worldwide, with rates varying significantly by country and maternal risk factors. Pregnancy IPV is associated with adverse newborn outcomes, including low birth weight and preterm birth. Many mechanisms for how IPV may impact birth outcomes have been proposed and include direct health, mental health, and behavioral effects, which all may interact. Screening for IPV during pregnancy is essential, yet due to time constraints and few clear recommendations for assessment, many prenatal providers do not routinely inquire about IPV, or even believe they should. More training is needed to assist health care providers in identifying and managing pregnancy IPV, with additional research needed to inform effective interventions to reduce the rates of pregnancy IPV and resultant outcomes.

Omega-3 fatty acid supplementation to prevent recurrent preterm birth: a randomized controlled trial

OBJECTIVE

To assess whether the addition of an omega-3 long-chain polyunsaturated fatty acid supplement would reduce preterm birth in women with at least one prior spontaneous preterm birth receiving 17alpha-hydroxyprogesterone caproate.

METHODS

We conducted a randomized, double-masked, placebo-controlled trial in 13 centers. Women with a history of prior spontaneous singleton preterm birth and a current singleton gestation were assigned to either a daily omega-3 supplement (1,200 mg eicosapentaenoic acid and 800 mg docosahexaenoic acid) or matching placebo from 16-22 through 36 weeks of gestation. All participants received weekly intramuscular 17alpha-hydroxyprogesterone caproate (250 mg). The primary study outcome was delivery before 37 weeks of gestation. A sample size of 800 was necessary to have 80% power to detect a 30% reduction in the primary outcome from 30%, assuming a type I error two-sided of 5%.

RESULTS

A total of 852 women were included, and none was lost to follow up. Delivery before 37 weeks of gestation occurred in 37.8% (164/434) of women in the omega-3 group and 41.6% (174/418) in the placebo group (relative risk 0.91, 95% confidence interval 0.77-1.07).

CONCLUSION

Omega-3 long-chain polyunsaturated fatty acid supplementation offered no benefit in reducing preterm birth among women receiving 17alpha-hydroxyprogesterone caproate who have a history of preterm delivery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT00135902.

LEVEL OF EVIDENCE

I.

The effect of 17-alpha hydroxyprogesterone caproate on the risk of gestational diabetes in singleton or twin pregnancies

OBJECTIVE

To compare the rates of gestational diabetes among women who received serial doses of 17-alpha hydroxyprogesterone caproate vs placebo.

STUDY DESIGN

Secondary analysis of 2 double-blind randomized placebo-controlled trials of 17-alpha hydroxyprogesterone caproate given to women at risk for preterm delivery. The incidence of gestational diabetes was compared between women who received 17-alpha hydroxyprogesterone caproate or placebo.

RESULTS

We included 1094 women; 441 had singleton and 653 had twin gestations. Combining the 2 studies, 616 received 17-alpha hydroxyprogesterone caproate and 478 received placebo. Among singleton and twin pregnancies, rates of gestational diabetes were similar in women receiving 17-alpha hydroxyprogesterone caproate vs placebo (5.8% vs 4.7%; P = .64 and 7.4% vs 7.6%; P = .94, respectively). In the multivariable model, progesterone was not associated with gestational diabetes (adjusted odds ratio, 1.04; 95% confidence interval, 0.62-1.73).

CONCLUSION

Weekly administration of 17-alpha hydroxyprogesterone caproate is not associated with higher rates of gestational diabetes in either singleton or twin pregnancies.

Effect of Lactobacillus rhamnosus GR-1 supernatant and fetal sex on lipopolysaccharide-induced cytokine and prostaglandin-regulating enzymes in human placental trophoblast cells: implications for treatment of bacterial vaginosis and prevention of preterm labor

OBJECTIVE

The objective of the study was to determine the effect of fetal sex on the output of cytokines and prostaglandin-regulating enzymes in lipopolysaccharide (LPS) and probiotic lactobacilli-treated placental trophoblast cells.

STUDY DESIGN

We examined the effect of LPS and Lactobacillus rhamnosus GR-1 supernatant in placental trophoblast cells on tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-10 using enzyme-linked immunosorbent assay and on prostaglandin-endoperoxide synthase 2 (PTGS2), 15-hydroxy prostaglandin dehydrogenase (PGDH), and toll-like receptor-4 (TLR-4) using Western blotting. Comparisons were performed using one-way analysis of variance and Student t test.

RESULTS

LPS increased the output of TNF-alpha, IL-10, and PTGS2 with a greater response in male placentae. L rhamnosus GR-1 supernatant inhibited the LPS-stimulated TNF-alpha and increased IL-10. It also up-regulated expression of PGDH in female placentae and partially reduced the LPS-stimulated PTGS2 in male placentae. There was no change in IL-1beta. Expression of TLR-4 was greater in placentae of male fetuses.

CONCLUSION

These findings suggest an underlying mechanism for the sex difference in the incidence of preterm birth and provide potential evidence for a therapeutic benefit of lactobacilli in reducing preterm labor.