Maternal, fetal, and placental conditions associated with medically indicated late preterm and early term delivery: a retrospective study

Perinatal Care Measures Are Incomplete If They Do Not Assess The Birth Parent-Infant Dyad As A Whole

Measures of perinatal care quality and outcomes often focus on either the birth parent or the infant. We used linked vital statistics and hospital discharge data to describe a dyadic measure (including both the birth parent and the infant) for perinatal care during the birth hospitalization. In this five-state cohort of 2010-18 births, 21.6 percent of birth parent-infant dyads experienced at least one complication, and 9.6 percent experienced a severe complication. Severe infant complications were eight times more prevalent than severe birth parent complications. Among birth parents with a severe complication, the co-occurrence of a severe infant complication ranged from 2 percent to 51 percent, whereas among infants with a severe complication, the co-occurrence of a severe birth parent complication was rare, ranging from 0.04 percent to 5 percent. These data suggest that measures, clinical interventions, public reporting, and policies focused on either the birth parent or the infant are incomplete in their assessment of a healthy dyad. Thus, clinicians, administrators, and policy makers should evaluate dyadic measures, incentivize positive outcomes for both patients (parent and infant), and create policies that support the health of the dyad.

Elevated human placental heat shock protein 5 is associated with spontaneous preterm birth

BACKGROUND

Specific heat shock proteins are associated with pregnancy complications, including spontaneous preterm birth (SPTB). Placental proteomics and whole exome sequencing recently suggested an association between heat shock protein HSPA5 and uncomplicated SPTB. In the present study, we investigated the localization of and possible roles for HSPA5 in SPTB.

METHODS

Western blot was performed to validate the result from the previously published proteomic analysis. We used qPCR to assess mRNA expression of genes and immunohistochemistry and immunoelectron microscopy to examine localization of HSPA5 in placental tissue. We silenced the HSPA5 gene in the HTR8/SVneo human trophoblast cell line to investigate possible functions of HSPA5.

RESULTS

HSPA5 was upregulated in placentas from SPTBs compared to spontaneous term births. We did not observe upregulation of HSPA5 mRNA in placental samples. The protein was localized in placental trophoblast in both spontaneous preterm and term placentas. Gene silencing of HSPA5 in human trophoblast cell culture affected the inflammatory response and decreased the expression of several proinflammatory genes.

CONCLUSIONS

We suggest that upregulation of HSPA5 in the placenta is associated with spontaneous preterm labor. HSPA5 may promote the inflammatory response and alter the anti-inflammatory state of the placenta which could eventually lead to premature labor.

IMPACT

We validated upregulation of HSPA5 in placentas from spontaneous preterm birth. HSPA5 was not upregulated at transcriptional level which suggests that it may be regulated post-translationally. Silencing HSPA5 in a human trophoblast-derived cell line suggested that HSPA5 promotes expression of proinflammatory cytokines. The emerging inflammation could lead to spontaneous preterm labor. Identifying inflammatory pathways and factors associated with spontaneous preterm birth increases knowledge of the molecular mechanisms of premature labor. This could provide cues to predict imminent premature labor and lead to information about how to safely maintain pregnancies.

Perinatal outcomes in twin late preterm pregnancies: results from an Italian area-based, prospective cohort study

BACKGROUND

Multiple gestations represent a considerable proportion of pregnancies delivering in the late preterm (LP) period. Only 30% of LP twins are due to spontaneous preterm labor and 70% are medically indicated; among this literature described that 16-50% of indicated LP twin deliveries are non-evidence based. As non-evidence-based delivery indications account for iatrogenic morbidity that could be prevented, the objective of our observational study is to investigate first neonatal outcomes of LP twin pregnancies according to gestational age at delivery, chorionicity and delivery indication, then non evidence-based delivery indications.

METHODS

Prospective cohort study among twins infants born between 34 + 0 and 36 + 6 weeks, in Emilia Romagna, Italy, during 2013-2015. The primary outcome was a composite of adverse perinatal outcomes.

RESULTS

Among 346 LP twins, 84 (23.4%) were monochorionic and 262 (75.7%) were dichorionic; spontaneous preterm labor accounted for 85 (24.6%) deliveries, preterm prelabor rupture of membranes for 66 (19.1%), evidence based indicated deliveries were 117 (33.8%), while non-evidence-based indications were 78 (22.5%). When compared to spontaneous preterm labor or preterm prelabor rupture of membranes, pregnancies delivered due to maternal and/or fetal indications were associated with higher maternal age (p <  0.01), higher gestational age at delivery (p <  0.01), Caucasian race (p 0.04), ART use (p <  0.01), gestational diabetes (p <  0.01), vaginal bleeding (p <  0.01), antenatal corticosteroids (p <  0.01), diagnosis of fetal growth restriction (FGR) (p <  0.01), and monochorionic (p <  0.01). Two hundred twenty-six pregnancies (65.3%) had at least one fetus experiencing one composite of adverse perinatal outcome. Multivariate analysis confirmed that delivery indication did not affect the composite of adverse perinatal outcomes; the only characteristic that affect the outcome after controlling for confounding was gestational age at delivery (p <  0.01). Moreover, there was at least one adverse neonatal outcome for 94% of babies born at 34 weeks, for 73% of those born at 35 weeks and for 46% of those born at 36 weeks (p <  0.01).

CONCLUSION

Our study suggests that the decision to deliver or not twins in LP period should consider gestational age at delivery as the main determinant infants' prognosis. Delivery indications should be accurately considered, to avoid iatrogenic early birth responsible of preventable complications.

Regionalization of neonatal care: benefits, barriers, and beyond

The goal of regionalization of neonatal care is to improve infant outcomes by directing patients to hospitals where risk-appropriate care is available. Although evidence shows that regionalized, risk-appropriate neonatal care decreases mortality, especially for high-risk infants, the approach and success of regionalization efforts in the U.S. and around the world is highly variable. Barriers to regionalization exist on the patient, provider, hospital, state, and national levels, which highlight potential opportunities to improve regionalization efforts. Improving neonatal regionalized care delivery requires a collaborative approach inclusive of all stakeholders from patients to national professional organizations, expansion and adaptation of current policies, changes to financial incentives, cross-state collaboration, support of national policies, and partnership between neonatal and obstetric communities to promote comprehensive, regionalized perinatal care.

Sustained Energy Deficit Following Perinatal Asphyxia: A Shift towards the Fructose-2,6-bisphosphatase (TIGAR)-Dependent Pentose Phosphate Pathway and Postnatal Development

Labor and delivery entail a complex and sequential metabolic and physiologic cascade, culminating in most circumstances in successful childbirth, although delivery can be a risky episode if oxygen supply is interrupted, resulting in perinatal asphyxia (PA). PA causes an energy failure, leading to cell dysfunction and death if re-oxygenation is not promptly restored. PA is associated with long-term effects, challenging the ability of the brain to cope with stressors occurring along with life. We review here relevant targets responsible for metabolic cascades linked to neurodevelopmental impairments, that we have identified with a model of global PA in rats. Severe PA induces a sustained effect on redox homeostasis, increasing oxidative stress, decreasing metabolic and tissue antioxidant capacity in vulnerable brain regions, which remains weeks after the insult. Catalase activity is decreased in mesencephalon and hippocampus from PA-exposed (AS), compared to control neonates (CS), in parallel with increased cleaved caspase-3 levels, associated with decreased glutathione reductase and glutathione peroxidase activity, a shift towards the TIGAR-dependent pentose phosphate pathway, and delayed calpain-dependent cell death. The brain damage continues long after the re-oxygenation period, extending for weeks after PA, affecting neurons and glial cells, including myelination in grey and white matter. The resulting vulnerability was investigated with organotypic cultures built from AS and CS rat newborns, showing that substantia nigra TH-dopamine-positive cells from AS were more vulnerable to 1 mM of H2O2 than those from CS animals. Several therapeutic strategies are discussed, including hypothermia; N-acetylcysteine; memantine; nicotinamide, and intranasally administered mesenchymal stem cell secretomes, promising clinical translation.

Maternal diseases and risk of hypertensive disorders of pregnancy across gestational age groups

OBJECTIVES

To estimate the risk of hypertensive disorders of pregnancy in nulliparous women with diabetes, chronic hypertension or obesity in three gestational age groups.

STUDY DESIGN

Population-based observational cohort study of 382 618 nulliparous women (94 280 with known BMI) using Medical Birth Registry of Norway and Statistics Norway. Main exposure variables were diabetes, chronic hypertension, Body Mass Index (BMI). Multiple regression analysis was performed without (model 1) and with (model 2) BMI.

MAIN OUTCOME MEASURES

Preeclampsia stratified by gestational age group at delivery: early (23⁰-33⁶ weeks), intermediate (34⁰-36⁶ weeks) and late (37⁰-43⁶ weeks), and gestational hypertension.

RESULTS

In model 1, Type 1 diabetes was associated with early (aOR = 5.0, 95%CI 3.8, 6.7), intermediate (aOR = 10.2, 95%CI 8.5, 12.3) and late preeclampsia (aOR = 2.7, 95%CI 2.4, 3.2), compared to no diabetes. Compared to normotensive women, women with chronic hypertension had an increased risk of preeclampsia in all groups: early (aOR = 8.68, 95%CI 6.94, 10.85), intermediate (aOR = 5.59, 95%CI 4.46, 7.02), late (aOR = 3.45, 95%CI 3.00, 3.96). The same trends persisted after adjusting for BMI (model 2). Obesity remained an independent risk factor for hypertensive disorders of pregnancy.

CONCLUSIONS

Maternal diabetes, chronic hypertension and obesity were associated with an increased risk of hypertensive disorders of pregnancy across all gestational age groups in nulliparous women. Adjusting for BMI did not further modify the risk in these women, although 75% of the women in the study lacked BMI data.

Pregnancy and Neonatal Outcomes Among Deaf or Hard of Hearing Women: Results From Nationally Representative Data

BACKGROUND

Although the literature suggests that women with disabilities are at increased risk for pregnancy complications and adverse birth outcomes, there are few population-based studies of the pregnancy outcomes among deaf and hard of hearing (DHH) women in the United States.

OBJECTIVE

To compare pregnancy complications and neonatal outcomes between deliveries to DHH and non-DHH women using national hospitalization discharge record data.

STUDY DESIGN

We used the 2007-2016 Healthcare Cost and Utilization Project National Inpatient Sample to compare pregnancy complications and outcomes among deliveries to DHH women with deliveries to non-DHH women using bivariate and Poisson regressions, controlling for sociodemographic, hospital, and clinical characteristics.

RESULTS

DHH women had an increased risk of adverse pregnancy outcomes and chronic medical conditions, including preexisting diabetes (relative risk [RR], 2.01; 95% confidence interval, 1.68-2.42; p < .001), gestational diabetes (RR, 1.31; 95% CI, 1.19-1.44; p < .001), chronic hypertension (RR, 1.51; 95% CI, 1.33-1.72; p < .001), preeclampsia and eclampsia (RR, 1.35; 95% CI, 1.21-1.51; p < .01), placenta previa (RR, 1.62; 95% CI, 1.22-2.16; p < .01), placental abruption (RR, 1.43; 95% confidence interval, 1.15-1.78; p < .01), labor induction (RR, 1.16; 95% CI, 1.05-1.27; p < .01), chorioamnionitis (RR, 1.43; 95% CI, 1.22-1.69; p < .001), cesarean delivery (RR, 1.09; 95% CI, 1.04-1.14; p < .001), premature rupture of membranes (RR, 1.34; 95% CI, 1.20-1.50; p < .001), antepartum hemorrhage (RR, 1.36; 95% CI, 1.13-1.64; p < .001), and postpartum hemorrhage (RR, 1.30; 95% CI, 1.13-1.49; p < .001). After adjustment for socioeconomic and hospital characteristics, the risk for gestational diabetes, preeclampsia and eclampsia, placenta previa, and chorioamnionitis remained unexplained.

CONCLUSIONS

DHH women are at an increased risk for adverse pregnancy, fetal, and neonatal outcomes, illuminating the need for awareness among obstetric and primary care providers as well as the need for systematic investigation of outcomes and evidence-based guidelines.

Preterm births in Iceland 1997-2016: Preterm birth rates by gestational age groups and type of preterm birth

BACKGROUND

The frequency of preterm births has been increasing globally, mainly due to a rise in iatrogenic late preterm births. The aim of this study was to assess the prevalence of preterm births in Iceland during 1997-2016 by type of preterm birth.

METHODS

This study included all live births in Iceland during 1997-2016 identified from the Icelandic Medical Birth Registry. Risk of preterm birth by time period was assessed with Poisson regression models adjusted for demographic variables and indications for iatrogenic births.

RESULTS

The study population included 87 076 infants, of which 4986 (5.7%) were preterm. The preterm birth rate increased from 5.3% to 6.1% (adjusted rate ratio [ARR] = 1.16, confidence interval [CI] = 1.07-1.26) between 1997-2001 and 2012-2016 overall. The increase was only evident in multiples (ARR 1.41, 95% CI 1.21-1.65), not singletons (1.07, 0.97-1.19). The rate of late preterm births (34-36 weeks) increased significantly (1.24, 1.14-1.40), and the rate of iatrogenic preterm births more than doubled during this period even after adjustment for identified medical indications (2.40, 2.00-2.88). The rate of spontaneous preterm births decreased during the study period (0.63, 0.55-0.73), and the rate of PPROM increased (1.31, 1.09-1.57). The most common contributing indications for iatrogenic births were fetal distress (26.2%), hypertensive disorders (18.2%), and severe preeclampsia (16.9%).

CONCLUSIONS

Preterm birth rates increased in multiples in Iceland between 1997 and 2016, and late and iatrogenic preterm births increased overall. The increase in iatrogenic preterm births remained significant after adjusting for medical indications, suggesting that other factors might be affecting the rise.

Iatrogenic late preterm birth: when is it recommended? A Delphi survey promoted by the Italian Society of Perinatal Medicine

BACKGROUND

The rate of iatrogenic Late Preterm (LP) Birth varies in different settings. This is due to the lack of strong evidence/guidelines on the management of the different maternal, fetal and placental complications affecting pregnancy in the LP window. Steroid prophylaxis is also under discussion.

AIM

To build recommendations about the management of main medical complications (pregestational diabetes, placenta previa, preeclampsia, cholestasis, p-PROM, intrauterine growth restriction -IUGR-) occurring in the LP period to reduce clinical heterogeneity.

METHODS

A group of Italian Perinatal experts were identified by Scientific Societies. A Delphi consensus methodology was used to reach agreement on different clinical sceneries. Two rounds of consultation by using a purpose built on-line survey and a third open panel discussion were performed.

RESULTS

The panel of 50 experts reached agreement for the vast majority of clinical sceneries (Placenta Previa, Preeclampsia, Diabetes, Cholestasis). Overall, there was agreement to be conservative at 34 weeks and in favor of delivery at 36 weeks. The management of p-PROM and mostly of IUGR were characterized by a minor degree of consensus. Corticosteroids were found necessary at the 34th week and unnecessary at the 36th week.

CONCLUSIONS

Besides providing some guidance on clinical indications for LP iatrogenic delivery, these results represent a stimulus for designing future trials investigating the grey areas in this field.

Phenotypic Classification of Preterm Birth Among Nulliparous Women: A Population-Based Cohort Study

OBJECTIVE

A classification model based on preterm birth clinical presentations (phenotypes) was proposed at the International Conference on Prematurity and Stillbirth, with calls for validation. This study sought to determine the distribution of clinical phenotypes of preterm birth among nulliparous women, their corresponding associations with maternal characteristics, and the odds ratios (ORs) of preterm Caesarean section and other adverse outcomes.

METHODS

A population-based cohort study was performed of all nulliparous women with singleton pregnancies (>20 weeks) who gave birth in a hospital in Ontario between 2012 and 2014. Logistic regression models were used to estimate adjusted ORs (Canadian Task Force Classification II-2).

RESULTS

Among 113 942 nulliparous women, 6.1% delivered at <37 weeks, at a mean gestational age of 33.9 weeks. Of those women, 34.1% did not meet the criteria for the presence of any clinical phenotype; 42.3% had one maternal, fetal, or placental condition; 22.3% had two clinical conditions; and 1.3% had three clinical conditions. The most common preterm birth phenotypes were worsening of maternal diseases (24.0%), intrauterine growth restriction (23.5%), and fetal distress (23.0%). Compared with preterm births without any significant clinical phenotype, those with maternal, fetal, or placental phenotypes were associated with increased odds of Caesarean section (adjusted ORs 2.70 [95% confidence interval [CI] 2.30-3.17], 1.66 [95% CI 1.36-2.03], and 6.49 [95% CI 4.29-9.80], respectively).

CONCLUSION

Approximately two thirds of nulliparous preterm births were grouped into distinct clinical phenotypes. This study demonstrated that outcomes varied across phenotypes, thus providing evidence of benefit for the phenotypic classification model.

Impact of the new guidelines on the management of premature rupture of membranes for the prevention of late preterm birth: an 11-year retrospective study

Objectives To evaluate the number of late preterm (LPT) births (between 34 0/7 and 36 6/7 weeks) that could have been prevented if expectant management of preterm premature rupture of membranes (PPROM) had been applied according to new recommendations. Methods A retrospective cohort study included all births at one Swiss center between January 1, 2002 and December 31, 2012. Births were categorized using an adapted evidence-based classification. Two scenarios were considered: best scenario (maximum averted cases) and a conservative scenario (minimum averted cases). Results Among 2017 LPT births (5.0% of all deliveries; n=40,609), 1122 (60.6%) women had PPROM. Spontaneous labor occurred in 473 (42.2%) cases and 649 (57.8%) had induction of labor or an elective cesarean section. In the latter group, 44 (6.8%) had evidence-based indications for LPT delivery and 605 (83.2%) had non-evidence-based indications. Depending on the scenario, the rate of avoided LPT cases would have varied between 4.2% (95% confidence interval [CI]: 3.4-5.2) if the conservative scenario was applied, and 30% (95% CI: 28.0-32.0) for the best scenario. Conclusion Adoption of new guidelines for the management of PPROM will prevent a considerable number of LPT births and help decrease the adverse effects and potential disability associated with late preterm infants.

International variations in the gestational age distribution of births: an ecological study in 34 high-income countries

Background

Few studies have investigated international variations in the gestational age (GA) distribution of births. While preterm births (22-36 weeks GA) and early term births (37-38 weeks) are at greater risk of adverse health outcomes compared to full term births (39-40 weeks), it is not known if countries with high preterm birth rates also have high early term birth rates. We examined rate associations between preterm and early term births and mean term GA by mode of delivery onset.

Methods

We used routine aggregate data on the GA distribution of singleton live births from up to 34 high-income countries/regions in 1996, 2000, 2004, 2008 and 2010 to study preterm and early term births overall and by spontaneous or indicated onset. Pearson correlation coefficients were adjusted for clustering in time trend analyses.

Results

Preterm and early term births ranged from 4.1% to 8.2% (median 5.5%) and 15.6% to 30.8% (median 22.2%) of live births in 2010, respectively. Countries with higher preterm birth rates in 2004-2010 had higher early term birth rates (r > 0.50, P < 0.01) and changes over time were strongly correlated overall (adjusted-r = 0.55, P < 0.01) and by mode of onset.

Conclusion

Positive associations between preterm and early term birth rates suggest that common risk factors could underpin shifts in the GA distribution. Targeting modifiable population risk factors for delivery before 39 weeks GA may provide a useful preterm birth prevention paradigm.

Epidemiology of late preterm and early term births - An international perspective

Late preterm (34-36 weeks of gestational age (GA)), and early term (37-38 weeks GA) birth rates among singleton live births vary from 3% to 6% and from 15% to 31%, respectively, across countries, although data from low- and middle-income countries are sparse. Countries with high preterm birth rates are more likely to have high early term birth rates; many risk factors are shared, including pregnancy complications (hypertension, diabetes), medical practices (provider-initiated delivery, assisted reproduction), maternal socio-demographic and lifestyle characteristics and environmental factors. Exceptions include nulliparity and inflammation which increase risks for preterm, but not early term birth. Birth before 39 weeks GA is associated with adverse child health outcomes across a wide range of settings. International rate variations suggest that reductions in early delivery are achievable; implementation of best practice guidelines for obstetrical interventions and public health policies targeting population risk factors could contribute to prevention of both late preterm and early term births.

Underlying maternal and pregnancy-related conditions account for a substantial proportion of neonatal morbidity in late preterm infants

AIM

We studied the impact of maternal and pregnancy-related conditions and the effect of gestational age itself, on the health of infants born late preterm.

METHODS

Singletons born in gestational weeks 34 + 0 to 41 + 6 in 1995-2013 in the southern region of Sweden were identified from a perinatal register. We found 14 030 infants born late preterm and 294 814 born at term. A hierarchical system was developed to examine the impact of pregnancy complications. The outcomes studied were as follows: neonatal death, central nervous system (CNS) or respiratory disease, infection, neonatal admission and respiratory support. Odds ratios (OR) and 95% confidence intervals (95% CI) were obtained using logistic regression analyses.

RESULTS

Late preterm infants were at increased risk for all outcomes compared to term infants, with adjusted ORs from 13.1 (95% CI: 12.7-13.6) for neonatal admission to 2.3 (95% CI: 1.8-2.9) for infections. Late preterm birth after preterm prelabour rupture of membranes was associated with an overall lower risk compared to late preterm births due to other causes. Exposure to antepartum haemorrhage or maternal diabetes increased the risk for CNS and respiratory morbidity.

CONCLUSION

Morbidity decreased in late preterm infants with increasing gestational age. Underlying conditions accounted for a substantial part of the morbidity.

Are risk factors for preterm and early-term live singleton birth the same? A population-based study in France

OBJECTIVES

To investigate whether risk factors for preterm (<37 weeks gestation) and early-term birth (37 and 38 weeks gestation) are similar.

DESIGN

Nationally representative cross-sectional study of births.

SETTING

France in 2010.

PARTICIPANTS

Live singleton births (n=14 326).

PRIMARY AND SECONDARY OUTCOME MEASURES

Preterm and early-term birth rates overall and by mode of delivery (spontaneous and indicated). Risk factors were maternal sociodemographic characteristics, previous preterm birth, height, prepregnancy body mass index (BMI) and smoking, assessed using multinomial regression models with full-term births 39 weeks and over as the reference group.

RESULTS

There were 5.5% preterm and 22.5% early-term births. Common risk factors were: a previous preterm delivery (adjusted relative risk ratio (aRRR) 8.2 (95% CI 6.2 to 10.7) and aRRR 2.4 (95% CI 2.0 to 3.0), respectively), short stature, underweight (overall and in spontaneous deliveries), obesity (in indicated deliveries only), a low educational level and Sub-Saharan African origin. In contrast, primiparity was a risk factor only for preterm birth, aRRR 1.8 (95% CI 1.5 to 2.2), while higher parity was associated with greater risk of early-term birth.

CONCLUSIONS

Most population-level risk factors were common to both preterm and early-term birth with the exception of primiparity, and BMI which differed by mode of onset of delivery. Our results suggest that preterm and early-term birth share similar aetiologies and thus potentially common strategies for prevention.