To explore international differences in the classification of births at extremely low gestation and the subsequent impact on the calculation of survival rates.
We used national data on births at 22 ...to 25 weeks' gestation from the United States (2014;
= 11 144), Canada (2009-2014;
= 5668), the United Kingdom (2014-2015;
= 2992), Norway (2010-2014;
= 409), Finland (2010-2015;
= 348), Sweden (2011-2014;
= 489), and Japan (2014-2015;
= 2288) to compare neonatal survival rates using different denominators: all births, births alive at the onset of labor, live births, live births surviving to 1 hour, and live births surviving to 24 hours.
For births at 22 weeks' gestation, neonatal survival rates for which we used live births as the denominator varied from 3.7% to 56.7% among the 7 countries. This variation decreased when the denominator was changed to include stillbirths (ie, all births 1.8%-22.3% and fetuses alive at the onset of labor 3.7%-38.2%) or exclude early deaths and limited to births surviving at least 12 hours (50.0%-77.8%). Similar trends were seen for infants born at 23 weeks' gestation. Variation diminished considerably at 24 and 25 weeks' gestation.
International variation in neonatal survival rates at 22 to 23 weeks' gestation diminished considerably when including stillbirths in the denominator, revealing the variation arises in part from differences in the proportion of births reported as live births, which itself is closely connected to the provision of active care.
Operative vaginal delivery (OVD) is considered safe if carried out by trained personnel. However, opportunities for training in OVD have declined and, given these shifts in practice, the safety of ...OVD is unknown. We estimated incidence rates of trauma following OVD in Canada, and quantified variation in trauma rates by instrument, region, level of obstetric care and institutional OVD volume.
We conducted a cohort study of all singleton, term deliveries in Canada between April 2013 and March 2019, excluding Quebec. Our main outcome measures were maternal trauma (e.g., obstetric anal sphincter injury, high vaginal lacerations) and neonatal trauma (e.g., subgaleal hemorrhage, brachial plexus injury). We calculated adjusted and stabilized rates of trauma using mixed-effects logistic regression.
Of 1 326 191 deliveries, 38 500 (2.9%) were attempted forceps deliveries and 110 987 (8.4%) were attempted vacuum deliveries. The maternal trauma rate following forceps delivery was 25.3% (95% confidence interval CI 24.8%-25.7%) and the neonatal trauma rate was 9.6 (95% CI 8.6-10.6) per 1000 live births. Maternal and neonatal trauma rates following vacuum delivery were 13.2% (95% CI 13.0%-13.4%) and 9.6 (95% CI 9.0-10.2) per 1000 live births, respectively. Maternal trauma rates remained higher with forceps than with vacuum after adjustment for confounders (adjusted rate ratio 1.70, 95% CI 1.65-1.75) and varied by region, but not by level of obstetric care.
In Canada, rates of trauma following OVD are higher than previously reported, irrespective of region, level of obstetric care and volume of OVD among hospitals. These results support a reassessment of OVD safety in Canada.
Please cite this paper as: Zhang X, Mumford S, Cnattingius S, Schisterman E, Kramer M. Reduced birthweight in short or primiparous mothers: physiological or pathological?. BJOG 2010;117:1248–1254.
...Objective Customisation of birthweight‐for‐gestational‐age standards for maternal characteristics assumes that variation in birth weight as a result of those characteristics is physiological, rather than pathological. Maternal height and parity are among the characteristics widely assumed to be physiological. Our objective was to test that assumption by using an association with perinatal mortality as evidence of a pathological effect.
Design Population‐based cohort study.
Setting Sweden.
Population A total of 952 630 singletons born at ≥28 weeks of gestation in the period 1992–2001.
Methods We compared perinatal mortality among mothers of short stature (<160 cm) versus those of normal height (≥160 cm), and primiparous versus multiparous mothers, using an internal reference of estimated fetal weight for gestational age. The total effects of maternal height and parity were estimated, as well as the effects of height and parity independent of birthweight (controlled direct effects). All analyses were based on fetuses at risk, using marginal structural Cox models for the estimation of total and controlled direct effects.
Main outcome measures Perinatal mortality, stillbirth, and early neonatal mortality.
Results The estimated total effect (HR; 95% CI) of short stature on perinatal death among short mothers was 1.2 (95% CI 1.1–1.3) compared with women of normal height; the effect of short stature independent of birthweight (controlled direct effect) was 0.8 (95% CI 0.6–1.0) among small‐for‐gestational‐age (SGA) births, but 1.1 (95% CI 1.0–1.3) among non‐SGA births. Similar results were observed for primiparous mothers.
Conclusions The effect of maternal short stature or primiparity on perinatal mortality is partly mediated through SGA birth. Thus, birthweight differences resulting from these maternal characteristics appear not only to be physiological, but also to have an important pathological component.
Summary
Despite an increase in absolute numbers, the age-standardized incidence of hip fractures in Singapore declined in the period 2000 to 2017. Among the three major ethnic groups, Chinese women ...had the highest fracture rates but were the only group to show a temporal decline.
Introduction
A study published in 2001 predicted a 30–50% increase in Singapore hip fracture incidence rates over the ensuing 30 years. To test that prediction, we examined the incidence of hip fracture in Singapore from 2000 to 2017.
Methods
We carried out a population-based study of hip fractures among Singapore residents aged ≥ 50 years. National medical insurance claims data were used to identify admissions with a primary discharge diagnosis of hip fracture. Age-adjusted rates, based on the age distribution of the Singapore population of 2000, were analyzed separately by sex and ethnicity (Chinese, Malay, or Indian).
Results
Over the 18-year study period, 36,082 first hip fractures were recorded. Total hip fracture admissions increased from 1487 to 2729 fractures/year in the years 2000 to 2017. Despite this absolute increase, age-adjusted fracture rates declined, with an average annual change of − 4.3 (95% CI − 5.0, − 3.5) and − 1.1 (95% CI − 1.7, − 0.5) fractures/100,000/year for women and men respectively. Chinese women had 1.4- and 1.9-fold higher age-adjusted rates than Malay and Indian women: 264 (95% CI 260, 267) versus 185 (95% CI 176, 193) and 141 (95% CI 132, 150) fractures/100,000/year, respectively. Despite their higher fracture rates, Chinese women were the only ethnic group exhibiting a decline, most evident in those ≥ 85 years, in age-adjusted fracture rate of − 5.3 (95% CI − 6.0, − 4.5) fractures/100,000/year.
Conclusion
Although the absolute number of fractures increased, steep drops in elderly Chinese women drove a reduction in overall age-adjusted hip fracture rates. Increases in the older population will lead to a rise in total number of hip fractures, requiring budgetary planning and new preventive strategies.
Background
Although pregnant women are considered at high risk for severe influenza disease, comparative studies of maternal influenza and birth outcomes have not been comprehensively summarised.
...Objective
To review comparative studies evaluating maternal influenza disease and birth outcomes.
Search strategy
We searched bibliographic databases from inception to December 2014.
Selection criteria
Studies of preterm birth, small‐for‐gestational‐age (SGA) birth or fetal death, comparing women with and without clinical influenza illness or laboratory‐confirmed influenza infection during pregnancy.
Data collection and analysis
Two reviewers independently ed data and assessed study quality.
Main results
Heterogeneity across 16 studies reporting preterm birth precluded meta‐analysis. In a subgroup of the highest‐quality studies, two reported significantly increased preterm birth (risk ratios (RR) from 2.4 to 4.0) following severe 2009 pandemic H1N1 (pH1N1) influenza illness, whereas those assessing mild‐to‐moderate pH1N1 or seasonal influenza found no association. Five studies of SGA birth showed no discernible patterns with respect to influenza disease severity (pooled odds ratio 1.24; 95% CI 0.96–1.59). Two fetal death studies were of sufficient quality and size to permit meaningful interpretation. Both reported an increased risk of fetal death following maternal pH1N1 disease (RR 1.9 for mild‐to‐moderate disease and 4.2 for severe disease).
Conclusions
Comparative studies of preterm birth, SGA birth and fetal death following maternal influenza disease are limited in number and quality. An association between severe pH1N1 disease and preterm birth and fetal death was reported by several studies; however, these limited data do not permit firm conclusions on the magnitude of any association.
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Comparative studies are limited in quality but suggest severe pandemic H1N1 influenza increases preterm birth.
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Comparative studies are limited in quality but suggest severe pandemic H1N1 influenza increases preterm birth.
Enamel hypoplasia (EH) is a prevalent developmental defect of teeth that can result from various insults, including prenatal nutrient deficiencies. This study aimed to evaluate the association ...between prenatal serum retinol deficiency and EH in the deciduous teeth of offspring at 2-y of age. A cohort of 1,450 pregnant women was enrolled, and their prenatal nutritional status was assessed between 12 and 14 wk of gestation. Maternal serum retinol, serum 25-hydroxyvitamin D (25OHD), hemoglobin, body mass index, and birth outcomes, infant feeding practices, family socioeconomic status, and demographic information were recorded. Oral health examinations were conducted for the children semiannually, and EH was diagnosed using the Modified DDE index on all the surfaces of erupted teeth. A modified Poisson regression analysis was used to assess the cumulative risk of EH over a period of 2-y. A total of 920 (63.4%) mother–child pairs completed the study, and the cumulative EH prevalence among offspring after 2-y of follow-up was 16.5% (N = 152; 87/1,114 children in the first year and 132/920 in the second year, with 20/920 having EH only in the first year). After adjusting for potential confounders, maternal serum retinol deficiency significantly increased the risk of deciduous EH (risk ratio RR, 2.0; 95% confidence interval CI, 1.1–3.7). In addition, deficient serum 25OHD (RR, 6.5; 95% CI, 4.0–10.7), caesarean delivery (RR, 1.6; 95% CI, 1.0–2.4), Muslim (RR, 2.9; 95% CI, 2.0–4.1) and Christian (RR, 2.4; 95% CI, 1.6–3.5) versus Hindu religions, and very preterm birth (RR, 1.7; 95% CI, 1.1–2.9) increased the risk of EH. Children presenting with EH had 2 or more teeth affected, and the maxillary incisors were the most frequently affected, followed by the first primary molars and canines. In conclusion, maternal serum retinol deficiency during the 12 to 14 wk of gestation may increase the risk of deciduous EH, besides the well-established 25OHD deficiency.
Objectives
We assessed the incidence, risk factors and adverse birth outcomes associated with elevated liver enzymes and low platelets (HELLP) syndrome.
Design
A retrospective population‐based cohort ...study.
Setting
Canada (excluding Quebec), 2012/2013–2015/2016.
Population
Mothers with a singleton hospital live birth or stillbirth at ≥24 weeks’ gestation (n = 1 078 323).
Methods
HELLP syndrome was identified using ICD‐10‐CA diagnostic code from delivery hospitalisation data. We used logistic regression to identify independent risk factors for HELLP syndrome by obtaining adjusted odds ratios (AOR) and 95% confidence intervals (CI), and to assess the associations with adverse outcomes.
Main outcome measures
Adverse maternal (e.g. eclampsia) and fetal/neonatal outcomes (e.g. intraventricular haemorrhage, perinatal death).
Results
The incidence of HELLP syndrome was 2.5 per 1000 singleton deliveries (n = 2663). Risk factors included: age ≥35 years, rural residence, nulliparity, parity ≥4, pre‐pregnancy and gestational hypertension and diabetes, assisted reproduction, chronic cardiac conditions, systemic lupus erythematosus, obesity, chronic hepatic conditions, placental disorders (e.g. fetomaternal transfusion) and congenital anomalies. PROM and age <25 years were inversely associated with HELLP syndrome (P‐values <0.05). Women with the syndrome had a 10‐fold higher maternal mortality (95% CI 1.6–84.3) and elevated severe maternal morbidity (9.6 versus 121.7 per 1000; AOR 12.5, 95% CI 11.1–14.1); and higher perinatal mortality (4.3 versus 21.0 per 1000; AOR 4.5, 95% CI 3.5–5.9) and perinatal mortality/severe neonatal morbidity (21.2 versus 202.4 per 1000; AOR 10.7, 95% CI 9.7–11.8).
Conclusion
HELLP syndrome is associated with specific pre‐pregnancy and pregnancy risk factors, higher rates of maternal death, and substantially higher severe maternal morbidity, perinatal mortality and severe neonatal morbidity.
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HELLP syndrome is associated with higher maternal death rate, and substantially higher severe maternal and neonatal morbidity, and perinatal mortality.
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HELLP syndrome is associated with higher maternal death rate, and substantially higher severe maternal and neonatal morbidity, and perinatal mortality.
Several studies of prenatal determinants and neonatal morbidity and mortality among very preterm births have resulted in unexpected and paradoxical findings. We aimed to compare perinatal death rates ...among cohorts of very preterm births (24-31 weeks) with rates among all births in these groups (≥24 weeks), using births-based and fetuses-at-risk formulations.
We conducted a cohort study of singleton live births and stillbirths ≥24 weeks' gestation using population-based data from the United States and Canada (2006-2015). We contrasted rates of perinatal death between women with or without hypertensive disorders, between maternal races, and between births in Canada vs the United States.
Births-based perinatal death rates at 24-31 weeks were lower among hypertensive than among non-hypertensive women (rate ratio RR 0.67, 95% CI 0.65-0.68), among Black mothers compared with White mothers (RR 0.94, 95%CI 0.92-0.95) and among births in the United States compared with Canada (RR 0.74, 95%CI 0.71-0.75). However, overall (≥24 weeks) perinatal death rates were higher among births to hypertensive vs non-hypertensive women (RR 2.14, 95%CI 2.10-2.17), Black vs White mothers (RR 1.86, 95%CI 184-1.88;) and births in the United States vs Canada (RR 1.08, 95%CI 1.05-1.10), as were perinatal death rates based on fetuses-at-risk at 24-31 weeks (RR for hypertensive disorders: 2.58, 95%CI 2.53-2.63; RR for Black vs White ethnicity: 2.29, 95%CI 2.25-2.32; RR for United States vs Canada: 1.27, 95%CI 1.22-1.30).
Studies of prenatal risk factors and between-centre or between-country comparisons of perinatal mortality bias causal inferences when restricted to truncated cohorts of very preterm births.
Macrophages promote tissue remodeling but few mechanisms exist to modulate their activity during tissue fibrosis. Serum amyloid P (SAP), a member of the pentraxin family of proteins, signals through ...Fcgamma receptors which are known to affect macrophage activation. We determined that IPF/UIP patients have increased protein levels of several alternatively activated pro-fibrotic (M2) macrophage-associated proteins in the lung and monocytes from these patients show skewing towards an M2 macrophage phenotype. SAP therapeutically inhibits established bleomycin-induced pulmonary fibrosis, when administered systemically or locally to the lungs. The reduction in aberrant collagen deposition was associated with a reduction in M2 macrophages in the lung and increased IP10/CXCL10. These data highlight the role of macrophages in fibrotic lung disease, and demonstrate a therapeutic action of SAP on macrophages which may extend to many fibrotic indications caused by over-exuberant pro-fibrotic macrophage responses.
Summary
Comorbidity and hip fracture independently increased mortality risk for 9 years in both sexes, with a significant additive interaction in the first year among women and through 6 years among ...men.
Introduction
Hip fracture is associated with a persistently elevated mortality risk, but it is unknown whether the elevated risk is due to the fracture or to pre-fracture comorbidity.
Methods
In a population-based study in Singapore with 9 years of follow-up, patients age
>
50 with first hip fracture from 2008 to 2017 were pair-matched to a cohort without hip fracture by age, sex, ethnicity, and pre-fracture Charlson Comorbidity Index (CCI). We investigated additive interaction using the relative excess risk due to interaction (RERI) and multiplicative interaction using the ratio of relative risks.
Results
Twenty-two thousand five hundred ninety of 22,826 patients with a first hip fracture in 2008–2017 were successfully matched. Hip fracture and comorbidity independently increased mortality risk for 9 years in both sexes. After adjustment for comorbidity, excess mortality risk continued to persist for 9 years post-fracture in both men and women. Women with a hip fracture and pre-fracture CCI
>
4 had a higher relative risk (RR) of mortality at 9 years of 3.29 95% confidence interval (CI) 3.01, 3.59 than those without comorbidity (RR 1.51, 95%CI 1.36, 1.68) compared to the referent without hip fracture or comorbidity. An additive interaction between hip fracture and pre-fracture CCI
>
4 was observed in the first post-fracture year` relative excess risk due to interaction (RERI) 1.99, 95%CI 0.97, 3.01. For men with CCI ≥ 4, the positive additive interaction was observed through 6 years.
Conclusions
Excess mortality risks post-fracture are attributable to both the fracture and pre-fracture comorbidity. Early interventions in hip fracture patients with high comorbidity could reduce their excess mortality.
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