Pediatric admissions that include intensive care: a population-based study.

BACKGROUND: Pediatric admissions to intensive care outside children's hospitals are generally excluded from registry-based studies. This study compares pediatric admission to specialist pediatric intensive care units (PICU) with pediatric admissions to intensive care units (ICU) in general hospitals in an Australian population. METHODS: We undertook a population-based record linkage cohort study utilizing longitudinally-linked hospital and death data for pediatric hospitalization from New South Wales, Australia, 2010-2013. The study population included all new pediatric, post-neonatal hospital admissions that included time in ICU (excluding neonatal ICU). RESULTS: Of 498,466 pediatric hospitalizations, 7525 (1.5%) included time in an intensive care unit - 93.7% to PICU and 6.3% to ICU in a general (non-PICU) hospital. Non-PICU admissions were of older children, in rural areas, with shorter stays in ICU, more likely admitted for acute conditions such as asthma, injury or diabetes, and less likely to have chronic conditions, receive continuous ventilatory support, blood transfusion, parenteral nutrition or die. CONCLUSIONS: A substantial proportion of children are admitted to ICUs in general hospitals. A comprehensive overview of pediatric ICU admissions includes these admissions and the context of the total hospitalization.

Long-term outcomes for large for gestational age infants born at term.

AIM: Large for gestational age (LGA) babies have increased risks for short-term outcomes such as shoulder dystocia, neonatal hypoglycaemia and longer hospital stay. Little is known of long-term health, development and educational outcomes of LGA babies. The aim of this study was to determine the long-term health, mortality, development and educational outcomes for infants born LGA at term. METHODS: A population-based record linkage study of live singletons born at term (37-41 weeks of gestation) in New South Wales, Australia, from 2001 to 2006. RESULTS: This study compared 49 439 LGA (>90th percentile for birthweight, gestational age and sex) and 400 418 appropriate size for gestational age (AGA; 10th-90th percentile) infants. LGA infants had increased risk of birth and neonatal outcomes and hospitalisations, for brachial plexus injury after the neonatal period, and for all causes from 1 to 5 years of age. There were no differences in mortality up to 5 years of age or hospitalisations for type 1 diabetes in childhood. LGA infants had lower rates of developmental vulnerability (in kindergarten) and showed a significant trend (χ2 for trend <0.0001) to fewer low scores and more high scores in reading and numeracy (in Year 3) compared with AGA. After adjusting for potential confounders, only the relative risk for higher reading scores was statistically significant. CONCLUSIONS: LGA infants show positive long-term health, development and educational outcomes. Concerns for LGA infants still remain in the perinatal period as a result of birth trauma; however, these complications usually do not persist in postnatal and early childhood.

Cervical cerclage placed before 14 weeks gestation in women with one previous midtrimester loss: A population-based cohort study.

BACKGROUND: Cervical cerclage is used in an attempt to reduce recurrence risk of preterm birth, but evidence for use is limited. AIMS: To compare pregnancy outcomes among women with a single previous midtrimester delivery when managed with or without a cervical cerclage. MATERIALS AND METHODS: Population-based cohort study of all women in New South Wales, Australia with a singleton pregnancy ending in birth/miscarriage ≥14 and <28 weeks, between 2003 and 2011. Modified Poisson regression was used to compare outcomes in the next subsequent pregnancy, for women with a cerclage inserted <14 weeks, and those without cerclage. The primary outcome was gestational age <37 weeks at birth/miscarriage in the next pregnancy. Secondary outcomes included: maternal morbidity, preterm prelabour rupture of membranes (PPROM), stillbirth/neonatal death and composite neonatal morbidity for liveborn infants ≥28 weeks. Adjusted risk ratios (ARR) and 95% confidence intervals (CI) were determined. RESULTS: Five thousand, six hundred and ninety-eight births/miscarriages were potential index deliveries. Of these, 2175 women had an eligible subsequent pregnancy: 108 received cerclage at <14 weeks gestation, 2067 did not. Women with cerclage were significantly more likely to deliver <37 weeks than those without (39.8% vs 19.3%, ARR 1.92, 95% CI 1.48-2.48), and had increased risks of PPROM (ARR 4.38, 95% CI 2.62-7.32) and stillbirth/neonatal death (ARR 2.20, 95% CI 1.02-4.73). Following cerclage, liveborn infants ≥28 weeks had double the risk of severe morbidity (ARR 2.54, 95% CI 1.55-4.16). CONCLUSIONS: In women with a single previous midtrimester delivery, cervical cerclage <14 weeks gestation in subsequent pregnancy was associated with worse pregnancy outcomes.

Early-onset preeclampsia appears to discourage subsequent pregnancy but the risks may be overestimated.

BACKGROUND: Early-onset preeclampsia is associated with adverse maternal and perinatal outcomes. For women who consider another pregnancy after one complicated by early-onset preeclampsia, the likelihood of recurrence and the subsequent pregnancy outcome for themselves and their babies are pertinent considerations. OBJECTIVES: The purpose of this study was to determine the subsequent pregnancy rate after a nulliparous pregnancy that was complicated by early-onset preeclampsia and among those who have a subsequent pregnancy, the risk of recurrence by gestational week, and adverse pregnancy outcomes. STUDY DESIGN: This was a population-based record linkage cohort study. The study population included nulliparous women with a singleton pregnancy and early-onset preeclampsia (<34 weeks gestation) who gave birth in New South Wales Australia from 2001-2010 (the index birth), with follow-up data for a subsequent birth through 2012. Early-onset in the index birth was further categorized as <28 vs 28-33 weeks gestation. Subsequent pregnancy outcomes that were assessed included the pregnancy rate, preeclampsia recurrence, and maternal and perinatal morbidity and mortality rates. The risk of preeclampsia necessitating delivery at each gestational week for women who were at risk was plotted, and the net gain or loss of gestational age when comparing the index with the subsequent pregnancy was calculated. RESULTS: Among 361,031 nulliparous women with singleton pregnancies, 1473 (0.4%) had early-onset preeclampsia. Women with early-onset preeclampsia in their first pregnancy had a lower subsequent pregnancy rate (59.7%) than women without preeclampsia (67.7%). Of the 758 women with a subsequent singleton birth, 256 (33.8%) experienced preeclampsia in the next pregnancy; 57 women (7.5%) with recurrent early-onset preeclampsia were included. Cumulative rates of preeclampsia in the subsequent pregnancy were higher at every gestation from 23 weeks gestation when the index birth was <28 weeks compared with 28-33 weeks gestation. The cumulative rate and gestation-specific risk of recurrent preeclampsia rose most steeply at 32-38 weeks gestation. Most women (94.6%) progressed to a later gestational age in their subsequent pregnancy. The median overall increase in gestational age at delivery was 6 weeks (interquartile range, 4-8); among women with recurrent preeclampsia, the median increase was 5 weeks (interquartile range, 2-7). Women with index birth <28 weeks gestation compared with 28-33 weeks gestation were more likely to deliver preterm (38.8% vs 28.7%; relative risk, 1.35; 95% confidence interval, 1.04-1.75) and have a perinatal death (4.3% vs 1.2%; relative risk, 3.46; 95% confidence interval, 1.15-10.39) at the subsequent birth, but live born infants had similar rates of severe morbidity (17.1% vs 15.0%; relative risk, 1.14; 95% confidence interval, 0.73-1.79). CONCLUSION: Women with early-onset preeclampsia in a first pregnancy appear less likely than women without preeclampsia to have a subsequent pregnancy. Maternal and perinatal outcomes in the subsequent pregnancy are generally better than in the first; most women will not have recurrent preeclampsia, and those who do usually will give birth at a greater gestational age compared with their index birth.

Immediate delivery compared with expectant management after preterm pre-labour rupture of the membranes close to term (PPROMT trial): a randomised controlled trial.

BACKGROUND: Preterm pre-labour ruptured membranes close to term is associated with increased risk of neonatal infection, but immediate delivery is associated with risks of prematurity. The balance of risks is unclear. We aimed to establish whether immediate birth in singleton pregnancies with ruptured membranes close to term reduces neonatal infection without increasing other morbidity. METHODS: The PPROMT trial was a multicentre randomised controlled trial done at 65 centres across 11 countries. Women aged over 16 years with singleton pregnancies and ruptured membranes before the onset of labour between 34 weeks and 36 weeks and 6 days weeks who had no signs of infection were included. Women were randomly assigned (1:1) by a computer-generated randomisation schedule with variable block sizes, stratified by centre, to immediate delivery or expectant management. The primary outcome was the incidence of neonatal sepsis. Secondary infant outcomes included a composite neonatal morbidity and mortality indicator (ie, sepsis, mechanical ventilation ≥24 h, stillbirth, or neonatal death); respiratory distress syndrome; any mechanical ventilation; and duration of stay in a neonatal intensive or special care unit. Secondary maternal outcomes included antepartum or intrapartum haemorrhage, intrapartum fever, postpartum treatment with antibiotics, and mode of delivery. Women and caregivers could not be masked, but those adjudicating on the primary outcome were masked to group allocation. Analyses were by intention to treat. This trial is registered with the International Clinical Trials Registry, number ISRCTN44485060. FINDINGS: Between May 28, 2004, and June 30, 2013, 1839 women were recruited and randomly assigned: 924 to the immediate birth group and 915 to the expectant management group. One woman in the immediate birth group and three in the expectant group were excluded from the primary analyses. Neonatal sepsis occurred in 23 (2%) of 923 neonates whose mothers were assigned to immediate birth and 29 (3%) of 912 neonates of mothers assigned to expectant management (relative risk [RR] 0·8, 95% CI 0·5-1·3; p=0·37). The composite secondary outcome of neonatal morbidity and mortality occurred in 73 (8%) of 923 neonates of mothers assigned to immediate delivery and 61 (7%) of 911 neonates of mothers assigned to expectant management (RR 1·2, 95% CI 0·9-1·6; p=0·32). However, neonates born to mothers in the immediate delivery group had increased rates of respiratory distress (76 [8%] of 919 vs 47 [5%] of 910, RR 1·6, 95% CI 1·1-2·30; p=0·008) and any mechanical ventilation (114 [12%] of 923 vs 83 [9%] of 912, RR 1·4, 95% CI 1·0-1·8; p=0·02) and spent more time in intensive care (median 4·0 days [IQR 0·0-10·0] vs 2·0 days [0·0-7·0]; p<0·0001) compared with neonates born to mothers in the expectant management group. Compared with women assigned to the immediate delivery group, those assigned to the expectant management group had higher risks of antepartum or intrapartum haemorrhage (RR 0·6, 95% CI 0·4-0·9), intrapartum fever (0·4, 0·2-0·9), and use of postpartum antibiotics (0·8, 0·7-1·0), and longer hospital stay (p<0·0001), but a lower risk of caesarean delivery (RR 1·4, 95% CI 1·2-1·7). INTERPRETATION: In the absence of overt signs of infection or fetal compromise, a policy of expectant management with appropriate surveillance of maternal and fetal wellbeing should be followed in pregnant women who present with ruptured membranes close to term. FUNDING: Australian National Health and Medical Research Council, the Women's and Children's Hospital Foundation, and The University of Sydney.

Increased planned delivery contributes to declining rates of pregnancy hypertension in Australia: a population-based record linkage study.

OBJECTIVE: Since the 1990s, pregnancy hypertension rates have declined in some countries, but not all. Increasing rates of early planned delivery (before the due date) have been hypothesised as the reason for the decline. The aim of this study was to explore whether early planned delivery can partly explain the declining pregnancy hypertension rates in Australia. DESIGN: Population-based record linkage study utilising linked birth and hospital records. SETTING AND PARTICIPANTS: A cohort of 1,076,122 deliveries in New South Wales, Australia, 2001-2012. OUTCOME MEASURES: Pregnancy hypertension (including gestational hypertension, pre-eclampsia and eclampsia) was the main outcome; pre-eclampsia was a secondary outcome. RESULTS: From 2001 to 2012, pregnancy hypertension rates declined by 22%, from 9.9% to 7.7%, and pre-eclampsia by 27%, from 3.3% to 2.4% (trend p<0.0001). At the same time, planned deliveries increased: prelabour caesarean section by 43% (12.9-18.4%) and labour inductions by 10% (24.8-27.2%). Many maternal risk factors for pregnancy hypertension significantly increased (p<0.01) over the study period including nulliparity, age ≥35 years, diabetes, overweight and obesity, and use of assisted reproductive technologies; some risk factors decreased including multifetal pregnancies, age <20 years, autoimmune diseases and previous pregnancy hypertension. Given these changes in risk factors, the pregnancy hypertension rate was predicted to increase to 10.5%. Examination of annual gestational age distributions showed that pregnancy hypertension rates actually declined from 38 weeks gestation and were steepest from 41 weeks; at least 36% of the decrease could be attributed to planned deliveries. The risk factors for pregnancy hypertension were also risk factors for planned delivery. CONCLUSIONS: It appears that an unanticipated consequence of increasing early planned deliveries is a decline in the incidence of pregnancy hypertension. Women with risk factors for hypertension were relatively more likely to be selected for early delivery.

Reduced breast milk feeding subsequent to cosmetic breast augmentation surgery.

OBJECTIVE: To determine the effect of cosmetic breast augmentation on subsequent infant feeding. PARTICIPANTS, DESIGN AND SETTING: Population-based record linkage study of women giving birth in New South Wales, January 2006 - December 2011. Birth records were linked longitudinally to maternal hospitalisations up to 11 years before birth. Breast augmentation was identified by surgical procedure codes in hospital records. MAIN OUTCOME MEASURES: Any breast milk feeding at discharge from birth care, and among infants receiving any breast milk, exclusive breast milk feeding. The before-and-after effect of breast augmentation was assessed among women who had the surgery between births. RESULTS: Among 378 389 women who gave birth in the study period, 892 (0.2%) had prior breast augmentation. Among women with breast augmentation, 705 (79%) provided any breast milk to their infant at discharge, compared with 89% among women without augmentation. After adjusting for sociodemographic and pregnancy factors, infants of women with breast augmentation were less likely to receive breast milk at discharge than infants of women without augmentation (adjusted relative risk [ARR], 0.90; 95% CI, 0.87-0.93). However, infants receiving breast milk were not more or less likely to receive breast milk exclusively (ARR, 0.99; 95% CI, 0.97-1.01). Women with augmentation surgery between births changed their breastfeeding behaviour (reduced rates), while those with no augmentation or augmentation before both births did not. CONCLUSIONS: Reduced rates of breast milk feeding among women who have undergone breast augmentation underscore the importance of identifying, supporting and encouraging women who are vulnerable to a lower likelihood of breastfeeding.

Treatment of vaginal candidiasis for the prevention of preterm birth: a systematic review and meta-analysis.

BACKGROUND: Recognition that ascending infection leads to preterm birth has led to a number of studies that have evaluated the treatment of vaginal infections in pregnancy to reduce preterm birth rates. However, the role of candidiasis is relatively unexplored. Our aim was to undertake a systematic review and meta-analysis to assess whether treatment of pregnant women with vulvovaginal candidiasis reduces preterm birth rates and other adverse birth outcomes. METHODS: We undertook a systematic review and meta-analysis of published randomised controlled trials (RCTs) in which pregnant women were treated for vulvovaginal candidiasis (compared to placebo or no treatment) and where preterm birth was reported as an outcome. Trials were identified by searching the Cochrane Central Register of Controlled Trials, Medline and Embase databases to January 2014. Trial eligibility and outcomes were pre-specified. Two reviewers independently assessed the studies against the agreed criteria and extracted relevant data using a standard data extraction form. Meta-analysis was used to calculate pooled rate ratios (RR) and 95% confidence intervals (CI) using a fixed-effects model. RESULTS: There were two eligible RCTs both among women with asymptomatic candidiasis, with a total of 685 women randomised. Both trials compared treatment with usual care (no screening for, or treatment of, asymptomatic candidiasis). Data from one trial involved a post-hoc subgroup analysis (n = 586) of a larger trial of treatment of 4,429 women with asymptomatic infections in pregnancy and the other was a pilot study (n = 99). There was a significant reduction in spontaneous preterm births in treated compared with untreated women (meta-analysis RR = 0.36, 95% CI = 0.17 to 0.75). Other outcomes were reported by one or neither trial. CONCLUSIONS: This systematic review found two trials comparing the treatment of asymptomatic vaginal candidiasis in pregnancy for the outcome of preterm birth. Although the effect estimate suggests that treatment of asymptomatic candidiasis may reduce the risk of preterm birth, the result needs to be interpreted with caution as the primary driver for the pooled estimate comes from a post-hoc (unplanned) subgroup analysis. A prospective trial with sufficient power to answer the clinical question 'does treatment of asymptomatic candidiasis in early pregnancy prevent preterm birth' is warranted. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42014009241.

Association of prelabor cesarean delivery with reduced mortality in twins born near term.

OBJECTIVE: To examine short-term and longer-term outcomes for twins born at or near term, comparing prelabor cesarean delivery with birth after a trial of labor. METHODS: This study was conducted on a retrospective cohort of twin pregnancies delivered at 36 weeks of gestation or greater from 2000 to 2009. Pregnancies with an antenatal death, lethal anomaly, birth weight discordance 25% or more, or birth weight less than 2,000 g or more than 4,000 g were excluded. Outcomes included severe hypoxia, stillbirth and neonatal death, and hospital admissions or death during the first 5 years of life. RESULTS: Approximately 45% of 7,099 twin pregnancies were delivered by prelabor cesarean delivery. Compared with delivery after labor, prelabor cesarean delivery was associated with significantly reduced risks of adverse neonatal and child outcomes including severe birth hypoxia (0.08% compared with 0.75%, relative risk 0.10, 95% confidence interval [CI] 0.04-0.26), neonatal death (0.00% compared with 0.15%, relative risk 0.05, 95% CI 0.00-0.82), and death up to 5 years of age (0.16% compared with 0.40%, relative risk 0.41, 95% CI 0.20-0.85). Whereas total mortality for first twins was similar after labor (0.15%) compared with prelabor cesarean delivery (0.16%), total mortality was four times more common in second twins born after labor (0.64%) compared with second twins born after prelabor cesarean delivery (0.16%). CONCLUSION: Compared with prelabor cesarean delivery, twin pregnancies at and beyond 36 weeks of gestation delivered after labor have increased risks for birth outcomes associated with hypoxia, with second twins having significantly increased mortality up to 5 years of age. However, the absolute mortality rate for relatively uncomplicated twin pregnancies delivered at or near term is low and needs to be balanced against maternal morbidity. LEVEL OF EVIDENCE: II.

The impact of cosmetic breast implants on breastfeeding: a systematic review and meta-analysis.

BACKGROUND: Cosmetic breast augmentation (breast implants) is one of the most common plastic surgery procedures worldwide and uptake in high income countries has increased in the last two decades. Women need information about all associated outcomes in order to make an informed decision regarding whether to undergo cosmetic breast surgery. We conducted a systematic review to assess breastfeeding outcomes among women with breast implants compared to women without. METHODS: A systematic literature search of Medline, Pubmed, CINAHL and Embase databases was conducted using the earliest inclusive dates through December 2013. Eligible studies included comparative studies that reported breastfeeding outcomes (any breastfeeding, and among women who breastfed, exclusive breastfeeding) for women with and without breast implants. Pairs of reviewers extracted descriptive data, study quality, and outcomes. Rate ratios (RR) and 95% confidence intervals (CI) were pooled across studies using the random-effects model. The Newcastle-Ottawa scale (NOS) was used to critically appraise study quality, and the National Health and Medical Research Council Level of Evidence Scale to rank the level of the evidence. This systematic review has been registered with the international prospective register of systematic reviews (PROSPERO): CRD42014009074. RESULTS: Three small, observational studies met the inclusion criteria. The quality of the studies was fair (NOS 4-6) and the level of evidence was low (III-2 - III-3). There was no significant difference in attempted breastfeeding (one study, RR 0.94, 95% CI 0.76, 1.17). However, among women who breastfed, all three studies reported a reduced likelihood of exclusive breastfeeding amongst women with breast implants with a pooled rate ratio of 0.60 (95% CI 0.40, 0.90). CONCLUSIONS: This systematic review and meta-analysis suggests that women with breast implants who breastfeed were less likely to exclusively feed their infants with breast milk compared to women without breast implants.

Heart valve prostheses in pregnancy: outcomes for women and their infants.

BACKGROUND: As the prognosis of women with prosthetic heart valves improves, an increasing number are contemplating and undertaking pregnancy. Accurate knowledge of perinatal outcomes is essential, assisting counseling and guiding care. The aims of this study were to assess outcomes in a contemporary population of women with heart valve prostheses undertaking pregnancy and to compare outcomes for women with mechanical and bioprosthetic prostheses. METHODS AND RESULTS: Longitudinally linked population health data sets containing birth and hospital admissions data were obtained for all women giving birth in New South Wales, Australia, 2000-2011. This included information identifying presence of maternal prosthetic heart valve. Cardiovascular and birth outcomes were evaluated. Among 1 144 156 pregnancies, 136 involved women with a heart valve prosthesis (1 per 10 000). No maternal mortality was seen among these women, although the relative risk for an adverse event was higher than the general population, including severe maternal morbidity (139 versus 14 per 1000 births, rate ratio [RR]=9.96, 95% CI 6.32 to 15.7), major maternal cardiovascular event (44 versus 1 per 1000, RR 34.6, 95% CI 14.6 to 81.6), preterm birth (183 versus 66 per 1000, RR=2.77, 95% CI 1.88 to 4.07), and small-for-gestational-age infants (193 versus 95 per 1000, RR=2.03, 95% CI 1.40 to 2.96). There was a trend toward increased maternal and perinatal morbidity in women with a mechanical valve compared with those with a bioprosthetic valve. CONCLUSIONS: Pregnancies in women with a prosthetic heart valve demonstrate an increased risk of an adverse outcome, for both mothers and infants, compared with pregnancies in the absence of heart valve prostheses. In this contemporary population, the risk was lower than previously reported.

Rate of spontaneous onset of labour before planned repeat caesarean section at term.

BACKGROUND: Guidelines recommend that, in the absence of compelling medical indications (low risk) elective caesarean section should occur after 38 completed weeks gestation. However, implementation of these guidelines will mean some women go into labour before the planned date resulting in an intrapartum caesarean section. The aim of this study was to determine the rate at which low-risk women planned for repeat caesarean section go into spontaneous labour before 39 weeks. METHODS: We conducted a population-based cohort study of women who were planned to have an elective repeat caesarean section (ERCS) at 39-41 weeks gestation in New South Wales Australia, 2007-2010. Labour, delivery and health outcome information was obtained from linked birth and hospital records for the entire population. Women with no pre-existing medical or pregnancy complications were categorized as 'low risk'. The rate of spontaneous labour before 39 weeks was determined and variation in the rate for subgroups of women was examined using univariate and multivariate analysis. RESULTS: Of 32,934 women who had ERCS as the reported indication for caesarean section, 17,314 (52.6%) were categorised as 'low-risk'. Of these women, 1,473 (8.5% or 1 in 12) had spontaneous labour or prelabour rupture of the membranes before 39 weeks resulting in an intrapartum caesarean section. However the risk of labour <39 weeks varied depending on previous delivery history: 25% (1 in 4) for those with spontaneous preterm labour in a prior pregnancy; 15% (1 in 7) for women with a prior planned preterm birth (by labour induction or prelabour caesarean) and 6% (1 in 17) among those who had only previously had a planned caesarean section at term. Smoking in pregnancy was also associated with spontaneous labour. Women with spontaneous labour prior to a planned CS in the index pregnancy were at increased risk of out-of-hours delivery, and maternal and neonatal morbidity. CONCLUSIONS: These findings allow clinicians to more accurately determine the likelihood that a planned caesarean section may become an intrapartum caesarean section, and to advise their patients accordingly.

Prosthetic heart valves in pregnancy: a systematic review and meta-analysis protocol.

BACKGROUND: Advances in surgical technique, prosthetic heart valve design, and anticoagulation have contributed to an overall improvement in morbidity and mortality in women with heart valve prostheses as well as increased feasibility of pregnancy. Previous work investigating the pregnancies of women with prosthetic valves has been directed largely toward understanding the influence of anticoagulation regimen. There has been little investigation on maternal and infant outcomes. The objective of this systematic review will be to assess the outcomes of pregnancy in women with heart valve prostheses in contemporary populations. METHODS/DESIGN: A systematic search of Medline, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and the Cochrane Library will be undertaken. Article titles and abstracts will be evaluated by two reviewers for potential relevance. Studies that include pregnancies occurring from 1995 onwards and where there are six or more pregnancies in women with heart valve prostheses included in the study population will be reviewed for potential inclusion. Primary outcomes of interest will be mortality (maternal and perinatal). Secondary outcomes will include other pregnancy outcomes. No language restrictions will be applied. Methodological quality and heterogeneity of studies will be assessed. Data extraction from identified articles will be undertaken by two independent reviewers using a uniform template. Meta-analyses will be performed to ascertain risk of adverse events and, where numbers are sufficient, by type of prosthesis and location as well as other subgroup analyses. DISCUSSION: Estimates of the risk of adverse events in recent pregnancies of women with heart valve prosthesis will provide better information for counselling and decision making. Given the improvements in prognosis of heart valve prosthesis recipients and the paucity of definitive data regarding optimal pregnancy management for these women, review of this topic is pertinent. REVIEW REGISTRATION: This protocol has been registered with the international prospective register of systematic reviews (PROSPERO) as number CRD42013006187, accessible online at http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013006187#.Utk7qNJ9Lf8.

Effects of maternal serum 25-hydroxyvitamin D concentrations in the first trimester on subsequent pregnancy outcomes in an Australian population.

BACKGROUND: Low serum 25-hydroxyvitamin D [25(OH)D] concentrations during pregnancy have been associated with adverse pregnancy outcomes in a few studies but not in other studies. OBJECTIVES: We assessed the serum 25(OH)D concentration at 10-14 wk of pregnancy and its association with adverse pregnancy outcomes and examined the predictive accuracy. DESIGN: In this nested case-control study, we measured serum 25(OH)D in 5109 women with singleton pregnancies who were attending first-trimester screening in New South Wales, Australia. Multivariate logistic regression was conducted to examine the association between low 25(OH)D concentrations and adverse pregnancy outcomes (small for gestational age, preterm birth, preeclampsia, gestational diabetes, miscarriage, and stillbirth). The predictive accuracy of models was assessed. RESULTS: The median (IQR) 25(OH)D concentration for the total population was 56.4 nmol/L (43.3-69.8 nmol/L). Serum 25(OH)D concentrations showed significant variation by parity, smoking, weight, season of sampling, country of birth, and socioeconomic status. After adjustment for maternal and clinical risk factors, low 25(OH)D concentrations were not associated with most adverse pregnancy outcomes. The area under the receiver operating characteristic curve (AUC) and likelihood ratio for a composite of severe adverse pregnancy outcomes of 25(OH)D concentrations <25 nmol/L were 0.51 and 1.44, respectively, and, for risk factors alone, were 0.64 and 2.87, respectively. The addition of 25(OH)D information to maternal and clinical risk factors did not improve the ability to predict severe adverse pregnancy outcomes (AUC: 0.64; likelihood ratio: 2.32; P = 0.39). CONCLUSION: Low 25(OH)D serum concentrations in the first trimester of pregnancy are not associated with adverse pregnancy outcomes and do not predict complications any better than routinely assessed clinical and maternal risk-factor information.

Predicting date of birth and examining the best time to date a pregnancy.

OBJECTIVE: To compare the estimated date of birth (eDOB) from the last menstrual period (LMP) and ultrasound scans at varying gestations (<7(0), 7(0)-10(6), 11(0)-14(0), 14(1)-19(6), and 20(0)-27(6)weeks) with the actual date of birth (aDOB). METHODS: In a retrospective study, data were analyzed from 18 708 women with spontaneous labor who delivered a single neonate without major anomalies in a local health district in Australia between 2007 and 2011. Data were sourced from a computerized population birth database. The study outcomes were duration of pregnancy expressed as total days, and the difference between aDOB and eDOB by dating method. RESULTS: Only 5% of births occurred on the eDOB, regardless of the dating method or timing of the dating. Approximately 66% of births occurred within 7days of the eDOB, and there was little difference among the ultrasound examinations performed at varying gestational weeks. The ultrasound scans at 11(0)-14(0)weeks of gestation performed as well as ultrasound scans conducted at other gestational ages. CONCLUSION: On a population basis, there were no meaningful differences in the prediction of date of birth by ultrasound scan date. An early dating scan (≤10weeks) is unnecessary if LMP is reliable.

Reducing caesarean section rates--no easy task.

To identify the greatest potential for reducing overall caesarean delivery rates, we used longitudinally linked data for women with consecutive births 2001-2009 to examine the likely impact of hypothetical risk-based scenarios. Among women with a first birth, singleton, vertex-presenting fetus at term, increasing the vaginal birth rate following induction of labour by 20% potentially has greatest impact, with a 12.1% relative decrease in the overall caesarean rate. The potential relative decrease in other scenarios ranged from 0.8 to 5.9%.