Age range for inclusion affects ascertainment by birth defects registers.

BACKGROUND: The South Australian Birth Defects Register (SABDR) has collected the date of diagnosis of notified birth defects since the 2005 birth year cohort. This study aims to document the age at diagnosis for each of the main diagnostic categories of birth defects, to produce a profile of when defects are diagnosed. METHODS: Deidentified data were extracted from the SABDR for birth years 2005 to 2007. Each birth defect was assigned to a mutually exclusive date of diagnosis category (termination/stillbirth; neonatal [birth-28 days]; 1 month-1 year; 1-2 years; 2-3 years; 3-4 years; 4-5 years; unspecified). Each defect was also grouped according to the International Classification of Diseases Ninth edition-British Paediatric Association major diagnostic categories (nervous, cardiovascular, respiratory, gastrointestinal, urogenital, musculoskeletal, chromosomal, metabolic, hematological/immune, other). RESULTS: There were 6419 defects identified in 3676 individuals, and 98.6% of defects had a diagnosis date recorded. Terminations of pregnancy/stillbirths accounted for 20.3% of defects notified, and a further 46.7% of defects were diagnosed within the neonatal period. A total of 81.5% of defects were diagnosed by 1 year of age. An additional 17.2% of defects were diagnosed between the ages of 1 and 5 years. There were wide differences in age at diagnosis between the major diagnostic categories. CONCLUSION: This study highlights the value of birth defect registers collecting information about birth defects from terminations of pregnancy, stillbirths, and live births up to a child's fifth birthday. Reviewing diagnosis date provides insight into the pattern of diagnosis of different birth defects. This provides valuable information to medical specialists and researchers regarding the interpretation of information from birth defect data collections. Birth Defects Research (Part A) 106:761-766, 2016. © 2016 Wiley Periodicals, Inc.

Biological sex and the risk of cerebral palsy in Victoria, Australia.

AIM: Males typically outnumber females in cerebral palsy (CP) cohorts. To better understand this 'male disadvantage' and provide insight into causal pathways to CP, this study used 1983 to 2009 Australian CP and population birth cohorts to identify associations and trends with respect to biological sex and CP. METHOD: Within birth gestation groups, sex ratios were calculated to evaluate any male excess in the CP cohort compared with livebirths, neonatal deaths, neonatal mortality and survival rates, neonatal survivors, and CP rates in survivors. Sex- and gestation-specific trends in neonatal mortality, CP rates, and CP sex ratios were assessed by plotting their annual frequencies and fitting quadratic curves. RESULTS: Over-representation of males in preterm live births partly explained the male excess in the CP cohort after preterm birth, especially at 28 to 31 weeks. Higher CP rates in male neonatal survivors also contributed to the male excess in CP, particularly at <28 and 37+ weeks. Higher neonatal mortality rates in males at all gestations had little impact on the CP sex ratio. There was no clearly discernible change over time in the CP sex ratio. INTERPRETATION: Gestation-specific associations between sex and CP provide insight into causal pathways to CP and suggest sex-specific differences in response to neuroprotective strategies.

Genetic and clinical contributions to cerebral palsy: a multi-variable analysis.

AIM: This study aims to examine single nucleotide polymorphism (SNP) associations with cerebral palsy in a multi-variable analysis adjusting for potential clinical confounders and to assess SNP-SNP and SNP-maternal infection interactions as contributors to cerebral palsy. METHODS: A case control study including 587 children with cerebral palsy and 1154 control children without cerebral palsy. Thirty-nine candidate SNPs were genotyped in both mother and child. Data linkage to perinatal notes and cerebral palsy registers was performed with a supplementary maternal pregnancy questionnaire. History of known maternal infection during pregnancy was extracted from perinatal databases. RESULTS: Both maternal and fetal carriage of inducible nitric oxide synthase SNP rs1137933 were significantly negatively associated with cerebral palsy in infants born at less than 32 weeks gestation after adjustment for potential clinical confounders and correction for multiple testing (odds ratio 0.55, 95% confidence interval 0.38-0.79; odds ratio 0.57, 95% confidence interval 0.4-0.82, respectively). Analysis did not show any statistically significant SNP-SNP or SNP-maternal infection interactions after correction for multiple testing. CONCLUSIONS: Maternal and child inducible nitric oxide synthase SNPs are associated with reduced risk of cerebral palsy in infants born very preterm. There was no evidence for statistically significant SNP-SNP or SNP-maternal infection interactions as modulators of cerebral palsy risk.

The Australian cerebral palsy research study--protocol for a national collaborative study investigating genomic and clinical associations with cerebral palsy.

AIM: Previous studies have proposed a link between the presence of specific single nucleotide polymorphisms (SNPs) and cerebral palsy and the majority of these associations remain to be confirmed or rejected by prospective studies with sufficient statistical power. Prior studies have also given little attention to the interaction of genomic characteristics and clinical risk factors. METHODS: This paper describes the design of a prospective case-control study to test these genetic associations in conjunction with more stringent data collection in respect to clinical features associated with pregnancy, particularly maternal infection. Here we consider the ethical requirements, our hypothesis that genetic susceptibility modifies the risk of cerebral palsy in the presence of perinatal environmental triggers, a priori primary and secondary aims, power calculations, participant recruitment strategies, data linkage, sampling methods of genetic material and subsequent SNP analysis, collection of clinical data and the proposed final statistical analysis.

A polymorphism in a staphylococcal enterotoxin receptor gene (T cell receptor BV3 recombination signal sequence) is not associated with unexplained sudden unexpected death in infancy in an Australian cohort.

Polymorphisms in genes that influence the expression of toxin receptors could contribute to Sudden Infant Death Syndrome (SIDS) and unexplained Sudden Unexpected Death in Infancy (uSUDI) for which there is evidence of toxin involvement. We aimed to determine whether TCRBV3S1 allele 2 could be involved in a staphylococcal toxic shock hypothesis for uSUDI. Observed frequencies of the TCRBV3S1*2 allele and genotype in 48 Australian uSUDI cases and 96 live comparison infants did not differ. In future the role of other toxin receptor gene polymorphisms deserves investigation.

Genetic susceptibility to viral exposure may increase the risk of cerebral palsy.

AIM: Cytokine polymorphisms may alter the fetal inflammatory response, increasing susceptibility to cerebral palsy (CP). This study investigates associations between selected inflammatory mediator and cytokine gene polymorphisms (Toll-like receptor-4 (TLR-4) Asp299Gly, interleukin-6 G-174C and interleukin-4 C-589T) and CP from 443 CP infants and 883 control infants. Results were correlated with viral nucleic acids in the same samples. RESULTS: At all gestational ages (GA), TLR-4 was associated with a decreased risk of developing CP (homozygous/heterozygous odds ratio (OR) 0.70, 95% confidence interval (CI) 0.50-0.98) and interleukin (IL)-6 was associated with an increased risk of developing hemiplegia (OR 1.38, 95% CI 1.05-1.83). For infants born 32-36 weeks GA, there was a tenfold increase in the risk of quadriplegic CP with homozygous/heterozygous IL-6 (OR 10.42, 95% CI 1.34-80.82). Viral exposure in combination with IL-4 in preterm infants was associated with a fourfold increased risk of quadriplegia (homozygous/heterozygous OR 4.25, 95% CI 1.21-14.95). In very preterm infants, the absence of detectable viral exposure in combination with IL-4 decreased the risk of developing CP (homozygous/heterozygous OR 0.31, 95% CI 0.13-0.76). CONCLUSION: Polymorphisms in TLR-4 may be associated with a decreased risk of CP. Polymorphisms in IL-6 or IL-4 may act as susceptibility genes, in the presence of viral exposure, for the development of hemiplegic and quadriplegic CP. These associations require confirmation but they suggest a hypothesis for CP causation due to double jeopardy from neurotropic viral exposure and genetic susceptibility to infection.

Association between Apolipoprotein E genotype and cerebral palsy is not confirmed in a Caucasian population.

Apolipoprotein E (APOE) plays a significant role in lipid metabolism and has been implicated in the growth and repair of injured neurons. Two small studies have suggested an association between APOE genotype and cerebral palsy. We investigated if APOE genotype is associated with an increased risk for cerebral palsy, influences the type of cerebral palsy or interacts with prenatal viral infection to influence risk of cerebral palsy. The population-based case-control study comprised newborn screening cards of 443 Caucasian patients with cerebral palsy and 883 Caucasian matched controls. APOE genotyping was performed on DNA extracted from dried blood spots. Allelic and genotypic frequencies did not differ between cases and controls and combined frequencies were 0.10 (epsilon2), 0.76 (epsilon3), 0.14 (epsilon4), 0.03 (epsilon2/epsilon2), 0.10 (epsilon2/epsilon3), 0.03 (epsilon2/epsilon4), 0.02 (epsilon4/epsilon4), 0.21 (epsilon3/epsilon4), 0.61 (epsilon3/epsilon3). APOE genotype was correlated with cerebral palsy, type of cerebral palsy, gestation at birth and the presence of viral nucleic acids detected in previous work. Analysis by gestational age (all gestational ages, >/=37, 32-36 and <32 weeks) and type of cerebral palsy (all types, diplegia, hemiplegia and quadriplegia) showed no association between APOE genotype and cerebral palsy in this Caucasian population. An association between prenatal viral infection, APOE genotype and cerebral palsy was not demonstrated. These results did not confirm an association between APOE genotype, cerebral palsy, type of cerebral palsy and prenatal infection in a Caucasian population. Given the low frequency of APOE epsilon2 and some of the heterozygote and homozygote combinations in this study, a larger study is assessing this further.

Mannose-binding lectin haplotypes may be associated with cerebral palsy only after perinatal viral exposure.

OBJECTIVE: The objective of the study was to investigate the associations between infection, polymorphisms in the mannose-binding lectin gene (MBL), and cerebral palsy (CP). STUDY DESIGN: This was a case-control study using deoxyribonucleic acid from newborn screening cards of 443 Caucasian CP cases and 883 Caucasian controls to screen for 6 polymorphisms within the MBL gene. These polymorphisms combine to create haplotypes with high (HYPA), intermediate (LYQA, LYPA), low (LXPA), and defective (HYPD, LYQC, LYPB) circulating MBL levels. RESULTS: chi(2) Analyses demonstrated significant differences between CP cases and controls (less than 37 weeks chi(2) 14.99, P = .02; less than 32 weeks chi(2) 13.62, P = .02). The MBL haplotype LYPA was associated with CP at all gestations (odds ratio [OR] 1.57, 95% confidence interval [CI], 1.00 to 2.46), less than 37 weeks (OR 2.43, 95% CI, 1.41 to 4.18), and less than 32 weeks (OR 2.54, 95% CI, 1.34 to 4.76). LYPA was also associated with hemiplegic CP for babies born at less than 37 weeks (OR 2.77, 95% CI, 1.02 to 7.26) and less than 32 weeks (OR 4.48, 95% CI, 1.55 to 12.65). HYPD was associated with quadriplegic CP at all gestations (OR 3.47, 95% CI, 1.41 to 8.31) as well as for babies born at less than 32 weeks (OR 7.86, 95% CI, 1.67 to 29.48). Subanalysis on samples previously testing positive for exposure to viral infection demonstrated similar patterns of significance as those presented above, whereas analysis on samples negative for exposure to viral infection showed no positive associations between any of the MBL haplotypes and CP. Potential type I error from multiple analyses is a caveat. CONCLUSION: MBL haplotypes LYPA or HYPD may be associated with an increased risk of CP in the presence of exposure to viral infection and may act as susceptibility factors for CP.

Genetic polymorphisms and spontaneous preterm birth.

OBJECTIVE: To examine whether selected genetic polymorphisms in the infant are associated with spontaneous preterm birth (less than 37 weeks) among children with or without later-diagnosed cerebral palsy. METHODS: Exploratory case-control study investigating the relationship of gestational age at delivery to 31 single nucleotide polymorphisms measured in newborn screening bloodspots. Among all 443 children with later-diagnosed cerebral palsy born to white women in South Australia in 1986-1999, 234 were born after spontaneous onset of labor, and 108 of these were preterm (gestational age less than 37 weeks). The comparison group was 549 infants born after spontaneous onset of labor, of whom 147 were preterm. Distributions of genotypic frequencies were examined in preterm compared with term infants with and without cerebral palsy. Genotyping was performed using a Taqman assay. RESULTS: In children without cerebral palsy, preterm birth after spontaneous onset of labor was more frequent in association with a variant of the beta2 adrenergic receptor gene (ADRB2 Q27E, P=.003), inducible nitric oxide synthase (iNOS or NOS2A, P=.042), or thrombomodulin (G127A, P=.006). Among children with cerebral palsy, preterm birth was associated with polymorphisms in genes for endothelial nitric oxide synthase (eNOS -922, P=.012), plasminogen activator inhibitor-2 (P=.015 and .019), and alpha adducin (ADD1, P=.047). CONCLUSION: We confirm previous observations that variants of the beta adrenergic receptor and of nitric oxide synthase are associated with prematurity, and suggest that genetic variants of the placental antifibrinolytic plasminogen activator inhibitor-2, and thrombomodulin and alpha adducin may be contributors to risk of spontaneous preterm birth. LEVEL OF EVIDENCE: II.

The association between inherited cytokine polymorphisms and cerebral palsy.

OBJECTIVE: The purpose of this study was to investigate associations between inherited cytokine polymorphisms and cerebral palsy. STUDY DESIGN: This was a case-control study that used DNA from the newborn infant screening cards of 443 white infants with cerebral palsy and 883 white control infants to test for the following cytokine polymorphisms: tumor necrosis factor-alpha-308, mannose-binding lectin-221, and 3 polymorphisms in exon-1 of the mannose-binding lectin gene at codon-52, -54, and -57. RESULTS: At all gestational ages mannose-binding lectin codon-54 increased the risk of the development of diplegia (homozygous or heterozygous odds ratio, 1.55; 95% CI, 1.03-2.32). For babies who were born at term, the risk of the development of quadriplegia was associated with heterozygous tumor necrosis factor-alpha (odds ratio, 1.82; 95% CI, 1.04-3.15), and mannose-binding lectin codon-54 was associated with diplegia (homozygous or heterozygous odds ratio, 2.12; 95% CI, 1.10-4.05). The presence of any polymorphism in mannose-binding lectin exon-1 at term approximately doubled the risk of the development of diplegia (odds ratio, 1.94; 95% CI, 1.05-3.62). Homozygous or heterozygous tumor necrosis factor-alpha was associated with hemiplegia for babies who were born at <32 weeks of gestation (odds ratio, 2.38; 95% CI, 1.02-5.58). Overall, the presence of any cytokine polymorphism was associated with cerebral palsy (odds ratio, 1.37; 95% CI, 1.02-1.84). CONCLUSION: Carriage of polymorphisms in the tumor necrosis factor-alpha and mannose-binding lectin genes are associated with an increased risk of cerebral palsy.

Associations between fetal inherited thrombophilia and adverse pregnancy outcomes.

OBJECTIVE: The purpose of this study was to investigate associations between fetal inherited thrombophilia and adverse pregnancy outcomes, including pregnancy-induced hypertensive disorders (PIHD), antepartum hemorrhage (APH), small-for-gestational age <10th percentile (SGA), and preterm birth (PTB). STUDY DESIGN: Seven hundred and seventeen cases and 609 controls were genotyped for Factor V Leiden (FVL, G1691A), Prothrombin gene mutation (PGM, G20210A), and Methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C using DNA from newborn screening cards. RESULTS: For babies born <28 weeks' gestation, PGM was associated with an increased risk of SGA (OR 6.40, 95%CI 1.66-24.71) and APH with SGA (OR 6.35, 95%CI 1.63-24.75). Homozygous MTHFR A1298C was associated with an increased risk of SGA for babies born 28-31 weeks gestation (OR 4.00, 95%CI 1.04-15.37), and with APH and SGA for babies born <32 weeks' gestation (OR 3.57, 95%CI 1.09-11.66). Homozygous MTHFR C677T was associated with a reduced risk of PTB and SGA (OR 0.52, 95%CI 0.28-0.96) for babies born 32 to 36 weeks' gestation. Homozygous FVL decreased the risk of PTB <32 weeks' gestation (OR 0.55, 95%CI 0.31-0.98). CONCLUSION: Fetal thrombophilic polymorphisms may be related to adverse pregnancy outcomes, in particular SGA.

Associations between inherited thrombophilias, gestational age, and cerebral palsy.

OBJECTIVE: This study was undertaken to investigate associations between inherited thrombophilic polymorphisms and cerebral palsy (CP) in a large case-control study. STUDY DESIGN: This is a population-based case-control study. Genomic DNA from newborn screening cards of 443 white CP cases and 883 white controls was tested for factor V Leiden (FVL, G1691A), prothrombin gene mutation (PGM, G20210A), and methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C. RESULTS: MTHFR C677T was associated with an increased risk of developing any CP (32-36 weeks' gestation, homozygous odds ratio [OR] 2.55, 95% CI 1.12-5.74; heterozygous OR 1.91, 95% CI 1.01-3.66). MTHFR C677T was also associated with diplegia at both less than 32 weeks' gestation (homozygous OR 2.76, 95% CI 1.21-6.12) and all gestations (heterozygous OR 1.58 95%, CI 1.02-2.45). For children less than 32 weeks, FVL homozygosity may be associated with an increase in the risk of developing quadriplegia (OR 9.12, 95% CI 0.86-53.71). MTHFR A1298C (heterozygous) was associated with a reduced risk of diplegia developing at 32 to 36 weeks' gestation (OR 0.16, 95% CI 0.02-0.70). There were no associations between any type of CP and thrombophilia for children born 37 weeks or greater. Heterozygous PGM and homozygous MTHFR C677T combined were associated with quadriplegia at all gestational ages (OR 5.33, 95% CI 1.06-23.25). CONCLUSION: MTHFR C677T approximately doubles the risk of CP in preterm infants. A combination of homozygous MTHFR C677T and heterozygous PGM increases the risk of quadriplegia 5-fold at all gestational ages.

The prevalence of inherited thrombophilias in a Caucasian Australian population.

AIMS: To describe the prevalence of four inherited thrombophilias and their combinations for the first time in a large Caucasian Australian population. METHODS: Newborn screening cards of 883 Caucasian babies born in South Australia in 1986-1999 were de-identified and tested for the following inherited thrombophilic polymorphisms: factor V Leiden (G1691A), prothrombin gene mutation (G20210A), methylenetetrahydrofolate reductase gene (MTHFR) C677T and A1298C, as well as compound heterozygosity for the MTHFR polymorphisms. RESULTS: The birth prevalences of heterozygosity and homozygosity for the four thrombophilic polymorphisms were: factor V Leiden 9.5% and 0.7%, prothrombin gene 4.1% and 0.2%, MTHFR C677T 37.3% and 12.4%, and MTHFR A1298C 38.3% and 11.8%, respectively. Compound heterozygosity for MTHFR C677T and A1298C was seen in 16.6% of the population. Overall, 64.2% and 24.5% of the population studied were homozygous and heterozygous, respectively, for at least one of the four polymorphisms studied. CONCLUSION: Inherited thrombophilic polymorphisms are common in the Caucasian Australian population. Knowledge of the background prevalence of these polymorphisms will allow further study of their associations in future disease research.

Antenatal causes of cerebral palsy: associations between inherited thrombophilias, viral and bacterial infection, and inherited susceptibility to infection.

UNLABELLED: Cerebral palsy rates of 2 in every 1,000 births have varied little over the last 40 years, despite improvements in obstetric care. In the past, cerebral palsy was thought to be due to poor obstetric care and management; however, epidemiological studies have refuted this, suggesting that there is usually an antenatal timing to the neuropathology of cerebral palsy. There are many known risk factors for cerebral palsy, including multiple gestation, prematurity, and low birth weight. Recently, intrauterine infection, maternal pyrexia, and the presence of thrombophilic disorders (thrombophilia) have been identified as major risk factors for subsequent cerebral palsy. This review examines the links between intrauterine infection, the fetal inflammatory response, and thrombophilia as possible causes of cerebral palsy. The interactions of viral or bacterial infections during pregnancy, normal or abnormal fetal cytokine responses, and hereditary fetal thrombophilias as antenatal causes of the neuropathology of cerebral palsy are now areas of research priority. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians LEARNING OBJECTIVES: After completion of this article, the reader will be able to describe the condition cerebral palsy, list the risk factors for the development of cerebral palsy, outline the ultrasound findings associated with cerebral palsy, and point out other conditions associated with cerebral palsy.

Neuroimaging findings in a series of children with cerebral palsy and congenital cytomegalovirus infection.

UNLABELLED: Congenital cytomegalovirus (cCMV) is a contributing cause of neurodevelopmental disabilities including cerebral palsy (CP). In this case series we reviewed the neuroimaging findings of children with CP and cCMV infection in the context of the children's clinical profile. PARTICIPANTS: Children with CP and laboratory confirmed cCMV (n=12) reported to the Australian CP Register, born in South Australia and Victoria, 1993-2006, with magnetic resonance imaging (MRI) and/or computerized tomography (CT) report available. Clinical details and neuroimaging findings were tabulated and compared to published literature. Children in this series were mostly born at term (n=8), with symptoms or signs of cCMV (n=10) and had spastic quadriplegia (n=9), epilepsy (n=8), intellectual deficit (n=12), communication (n=10) and hearing impairments (n=9). All but one had abnormal neuroimaging findings reported on MRI or CT (n=11): most commonly brain malformations including disorders of neuronal migration (n=10), such as lissencephaly, pachygyria and polymicrogyria, and cerebellar hypoplasia (n=5). Other findings included ventricular dilatation (n=8), calcifications (n=7) and white matter abnormalities (n=6). This study suggests that brain malformations, calcifications, ventricular dilatation and cerebellar hypoplasia are common neuroimaging patterns in children with CP and cCMV infection. The presence of these findings should prompt investigations for congenital cytomegalovirus.

Fetal and maternal candidate single nucleotide polymorphism associations with cerebral palsy: a case-control study.

OBJECTIVE: Previous studies have suggested associations between certain genetic variants and susceptibility to cerebral palsy (CP). This study was designed to assess established and novel maternal and child genetic and epidemiologic risk factors for CP along with their interactions. METHODS: DNA from 587 case and 1154 control mother-child pairs was analyzed. A panel of 35 candidate single nucleotide polymorphisms (SNPs) were examined and included SNPs in genes associated with (1) thrombophilia, (2) inflammation, and (3) risk factors for CP (eg, preterm birth). Comparisons were specified a priori and made by using a χ(2) test. RESULTS: There were 40 fetal and 28 maternal associations with CP when analyzed by CP subtype, gestational age, genotypes of apolipoprotein E, and haplotypes of mannose-binding-lectin. After Bonferroni correction for multiple testing, no fetal or maternal candidate SNP was associated with CP or its subtypes. Only fetal carriage of prothrombin gene mutation remained marginally associated with hemiplegia in term infants born to mothers with a reported infection during pregnancy. Odds ratio directions of fetal SNP associations were compared with previously reported studies and confirmed no trend toward association. CONCLUSIONS: Except for the prothrombin gene mutation, individual maternal and fetal SNPs in our candidate panel were not found to be associated with CP outcome. Past reported SNP associations with CP were not confirmed, possibly reflecting type I error from small numbers and multiple testing in the original reports.

CD14 (C-260T) polymorphism is not associated with sudden infant death syndrome (SIDS) in a large South Australian cohort.

Similarities have been drawn between models of endotoxic shock and gross and microscopic pathology observed in sudden infant death syndrome (SIDS) cases. Polymorphisms in genes that influence the expression of endotoxin receptors could affect the outcome of toxaemia, and could, therefore, play a role in SIDS. The CD14 gene promoter contains a single nucleotide polymorphism that affects the level of CD14 gene expression. The TT genotype of the CD14 (C-260T) polymorphism causes a significantly higher density of CD14 receptor expression on monocytes which makes the individual more sensitive to endotoxin than those with the wild-type (CC). This investigation was designed to determine whether SIDS infants have a higher frequency of the CD14 (C-260T) polymorphism compared with non-SIDS controls. One hundred and sixteen SIDS and 228 control infants were genotyped using PCR followed by restriction fragment length analysis of amplified product. Carriage of the TT or CT genotypes did not significantly differ between SIDS and control infants (P = 0.218 and 0.081, respectively). The frequencies observed in the control group were consistent with Hardy-Weinberg equilibrium and did not differ significantly from the published frequencies in Caucasian Australians. These results suggest that CD14 (C-260T) polymorphism is unlikely to be implicated in SIDS.

Fetal MBL2 haplotypes combined with viral exposure are associated with adverse pregnancy outcomes.

OBJECTIVE: To investigate the roles of inherited polymorphisms in the MBL2 gene and exposure to viral infection in the development of a range of adverse pregnancy outcomes, including birthweight  < 10th percentile (small-for-gestational age, SGA), antepartum hemorrhage (APH), pregnancy-induced hypertensive disorders (PIHD), and preterm birth (PTB). METHODS: This was a case-control study using DNA from newborn screening cards of 717 cases (babies with at least one of the adverse pregnancy outcomes listed above) and 609 controls, to screen for six polymorphisms within the MBL2 gene. These combine to create haplotypes with high (HYPA), intermediate (LYQA, LYPA), low (LXPA), and defective (HYPD, LYQC, LYPB) circulating MBL2 levels. RESULTS: Significant associations were found between variant MBL2 haplotypes and SGA (LYPA  < 32 weeks OR 5.37, 95% CI 1.50-17.27), antepartum hemorrhage (LYPA  < 37 weeks OR 2.29, 95% CI 1.25-4.18), and PIHD (LYQC < 32 weeks (OR 17.89, 95% CI 2.20-139.57). Evidence of exposure to infection increased the effect of these associations, (SGA OR 17.00, 95% CI 1.03-252.48; APH OR 5.67, 95% CI 1.73-18.84; PIHD OR 23.80, 95% CI 1.08-1414.76), while no evidence of exposure to infection demonstrated no associations. PTB was significantly associated with the defective HYPD haplotype with evidence of exposure to infection (OR 6.14, 95% CI 1.21-29.89). CONCLUSIONS: This research suggests that the combination of fetal MBL2 haplotypes and exposure to in utero viral infection increases the risk of adverse pregnancy outcomes, including PTB, antepartum hemorrhage, small-for-gestational age and PIHD.

Epidemiologic associations with cerebral palsy.

OBJECTIVE: To estimate epidemiologic risk factors for cerebral palsy. METHODS: Data were collected by linkage to state-based perinatal repositories and cerebral palsy registers and using a maternal questionnaire. The cohort included 587 individuals with cerebral palsy and 1,154 non-cerebral palsy controls. RESULTS: The following factors were associated with cerebral palsy: recorded maternal infection during pregnancy (41.4% patients compared with 31.3% controls; odds ratio [OR] 1.55, 95% confidence interval 1.26-1.91), small for gestational age ([birth weight less than third customized centile] 43.9% patients compared with 6.3% controls; OR 11.75, 6.25-22.08), gestational age less than 32 weeks (29.3% patients compared with 0.7% controls; OR 59.20, 28.87-121.38), multiple birth (OR 6.62, 4.00-10.95), a relative with cerebral palsy (OR 1.61, 1.12-2.32), breech position (13.7% patients compared with 6.0% controls; OR 2.48, 1.76-3.49), bleeding at any time in pregnancy (29.3% patients compared with 16.9% controls; OR 2.04, 1.61-2.58), male sex (58.8% patients compared with 45.8% controls; OR 1.68, 1.38-2.06), multiple miscarriage (7.7% patients compared with 3.5% controls; OR 2.30, 1.38-3.82), smoking (14.0% patients compared with 10.6% controls; OR 1.37, 1.02-1.85), and illicit drug use (3.3% patients compared with 1.5% controls; OR 2.22, 1.14-4.30). Factors not associated with cerebral palsy were "disappearing twin," diabetes, maternal body mass index, hypertension, alcohol consumption, anemia, maternal hypothyroidism, forceps or vacuum delivery, and maternal age. CONCLUSION: Preterm birth, intrauterine growth restriction, perinatal infection, and multiple birth present the largest risks for a cerebral palsy outcome. Reassuringly, upper respiratory tract and gastrointestinal infections during pregnancy were not associated with cerebral palsy. LEVEL OF EVIDENCE: II.

Comparison of DNA extraction methods from small samples of newborn screening cards suitable for retrospective perinatal viral research.

Reliable detection of viral DNA in stored newborn screening cards (NSC) would give important insight into possible silent infection during pregnancy and around birth. We sought a DNA extraction method with sufficient sensitivity to detect low copy numbers of viral DNA from small punch samples of NSC. Blank NSC were spotted with seronegative EDTA-blood and seropositive EBV EDTA-blood. DNA was extracted with commercial and noncommercial DNA extraction methods and quantified on a spectrofluorometer using a PicoGreen dsDNA quantification kit. Serial dilutions of purified viral DNA controls determined the sensitivity of the amplification protocol, and seropositive EBV EDTA-blood amplified by nested PCR (nPCR) validated the DNA extraction methods. There were considerable differences between the commercial and noncommercial DNA extraction methods (P=0.014; P=0.016). Commercial kits compared favorably, but the QIamp DNA micro kit with an added forensic filter step was marginally more sensitive. The mean DNA yield from this method was 3 ng/µl. The limit of detection was 10 viral genome copies in a 50-µl reaction. EBV nPCR detection in neat and 1:10 diluted DNA extracts could be replicated reliably. We conclude that the QIamp Micro DNA extraction method with the added forensic spin-filter step was suitable for retrospective DNA viral assays from NSC.