Routine ultrasound examination at 41 weeks of gestation and risk of post-term severe adverse fetal outcome: a retrospective evaluation of two units, within the same hospital, with different guidelines

Is there a relation between stillbirth and low levels of vitamin D in the population? A bi-national follow-up study of vitamin D fortification

BACKGROUND

Stillbirth has been associated with low plasma vitamin D. Both Sweden and Finland have a high proportion of low plasma vitamin D levels (< 50 nmol/L). We aimed to assess the odds of stillbirth in relation to changes in national vitamin D fortification.

METHODS

We surveyed all pregnancies in Finland between 1994 and 2021 (n = 1,569,739) and Sweden (n = 2,800,730) with live or stillbirth registered in the Medical Birth Registries. The mean incidences before and after changes in the vitamin D food fortification programs in Finland (2003 and 2009) and Sweden (2018) were compared with cross-tabulation with 95% confidence intervals (CI).

RESULTS

In Finland, the stillbirth rate declined from ~ 4.1/1000 prior to 2003, to 3.4/1000 between 2004 and 2009 (odds ratio [OR] 0.87, 95% CI 0.81-0.93), and to 2.8/1000 after 2010 (OR 0.84, 95% CI 0.78-0.91). In Sweden, the stillbirth rate decreased from 3.9/1000 between 2008 and 2017 to 3.2/1000 after 2018 (OR 0.83, 95% CI 0.78-0.89). When the level of the dose-dependent difference in Finland in a large sample with correct temporal associations decreased, it remained steady in Sweden, and vice versa, indicating that the effect may be due to vitamin D. These are observational findings that may not be causal.

CONCLUSION

Each increment of vitamin D fortification was associated with a 15% drop in stillbirths on a national level. If true, and if fortification reaches the entire population, it may represent a milestone in preventing stillbirths and reducing health inequalities.

Delivery prediction by quantitative analysis of four steroid metabolites with liquid chromatography tandem mass spectrometry in asymptomatic pregnant women

BACKGROUND

Prediction of delivery is important for assessing due dates, providing adequate prenatal care, and suggesting appropriate interventions in preterm and post-term pregnancies. Recent metabolomic findings suggested that the temporal abundance information of metabolome can be used to predict delivery timing with high accuracy in a cohort of healthy women. However, a targeted and quantitative assay is required to further validate the clinical performance and utility of this group of metabolomic candidates in delivery prediction with a larger and independent cohort.

METHOD

LC-MS/MS quantitative assays were applied to determine the plasma concentrations of four steroid metabolites, including oestriol-16-glucuronide (E3-16-Gluc), 17-alpha-hydroxyprogesterone (17-OHP), tetrahydrodeoxycorticosterone (THDOC), and androstane-3,17-diol (A-3,17-Diol) in asymptomatic women of singleton pregnancies (≥30^th gestational weeks). Subsequent statistical analysis was conducted to assess the performance of the above candidates in delivery prediction.

RESULT

Using LC-MS/MS, four steroids were separated and quantified in 5.5 min. The coefficients of variation (CVs) of the four analytes at the lower limit of quantification ranged from 7.9% to 14.6%, with the R² values greater than 0.990 in the calibration curves. Of the 585 recruited pregnant women who ended up with spontaneous delivery, 17.1% and 82.9% of the subjects delivered within and after 7 days since plasma collection, respectively. In the receiver operator curve analysis, the gestational age-adjusted area under the curve of the combined measurements of E3-16-Gluc and 17-OHP was 0.69 (95% CI: 0.60-0.76), with the sensitivity of 87.0% (95% CI: 78.8%-92.9%) and specificity of 60.2% (95% CI: 55.7%-64.6%). Moreover, the positive and the negative predictive values were 28.3%-34.0% and 93.1%-97.4% respectively for this combined panel.

CONCLUSION

We performed analytical and clinical validation of a quantitation LC-MS/MS panel for the four steroids in the plasma of pregnant women. The steroid metabolites panel of E3-16-Gluc and 17-OHP was potentially useful for predicting delivery within one week in asymptomatic women of singleton pregnancies. Key messagesA quantitative LC-MS/MS assay for determining the plasma levels of 17-OHP, THDOC, A-3,17-Diol and E3-16-Gluc was developed and validated, in order to evaluate their predictive performance in asymptomatic delivery of singleton pregnancy. The levels of E3-16-Gluc and 17-OHP were found to be significantly elevated at the time of sampling in women that delivered within one week and their combinational testing may be potentially useful in delivery prediction.

Stillbirth in term and late term gestations in Stockholm during a 20-year period, incidence and causes

Introduction

The incidence of stillbirth has decreased marginally or remained stable during the past decades in high income countries. A recent report has shown Stockholm to have a lower incidence of stillbirth at term than other parts of Sweden. The risk of antepartum stillbirth increases in late term and postterm pregnancies which is one of the factors contributing to the current discussion regarding the optimal time of induction of labor due to postterm pregnancy.

Material and methods

This is a cohort study based on the Stockholm Stillbirth Database which contains all cases of stillbirth from 1998-2018 in Stockholm County. All cases were reviewed systematically and the cause of death was evaluated according to the Stockholm Stillbirth Classification. Stillbirths diagnosed between gestational week (GW) 37+0 and 40+6 n = 605 were compared to stillbirths diagnosed from GW 41+0 and onwards n = 157, according to the cause of stillbirth and pregnancy and maternal characteristics. The aim was to evaluate the incidence of stillbirth over time and the incidence of stillbirth diagnosed from GW 41+0.

Results

In Stockholm County the overall incidence of stillbirth has decreased from 4.6/1000 births during the period 1998-2004 to 3.4/1000 births during the period 2014-2018, p-value <0.001. When comparing the same time periods, the incidence of stillbirth diagnosed from GW 41+0 and onwards has decreased from 0.5/1000 births to 0.15/1000 births, p-value <0.001. Among women still pregnant at GW 41+0 the incidence of stillbirth has decreased from 1.8/ 1000 to 0.5/ 1000. When comparing stillbirths diagnosed at GW 37+0-40+6 with stillbirths diagnosed from GW 41+0 and onwards infection was a more common cause of stillbirth in the latter group.

Conclusion

In Stockholm County there was a decreasing incidence of stillbirth overall and in stillbirths diagnosed from 41+0 weeks of gestation and onwards during the period 1998-2018. In stillbirths diagnosed from GW 41+0 and onwards infection was a more common cause of death compared to stillbirths diagnosed between GW 37+0 and 40+6.

Induction of labour at 41 weeks or expectant management until 42 weeks: A systematic review and an individual participant data meta-analysis of randomised trials

BACKGROUND

The risk of perinatal death and severe neonatal morbidity increases gradually after 41 weeks of pregnancy. Several randomised controlled trials (RCTs) have assessed if induction of labour (IOL) in uncomplicated pregnancies at 41 weeks will improve perinatal outcomes. We performed an individual participant data meta-analysis (IPD-MA) on this subject.

METHODS AND FINDINGS

We searched PubMed, Excerpta Medica dataBASE (Embase), The Cochrane Library, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and PsycINFO on February 21, 2020 for RCTs comparing IOL at 41 weeks with expectant management until 42 weeks in women with uncomplicated pregnancies. Individual participant data (IPD) were sought from eligible RCTs. Primary outcome was a composite of severe adverse perinatal outcomes: mortality and severe neonatal morbidity. Additional outcomes included neonatal admission, mode of delivery, perineal lacerations, and postpartum haemorrhage. Prespecified subgroup analyses were conducted for parity (nulliparous/multiparous), maternal age (<35/≥35 years), and body mass index (BMI) (<30/≥30). Aggregate data meta-analysis (MA) was performed to include data from RCTs for which IPD was not available. From 89 full-text articles, we identified three eligible RCTs (n = 5,161), and two contributed with IPD (n = 4,561). Baseline characteristics were similar between the groups regarding age, parity, BMI, and higher level of education. IOL resulted overall in a decrease of severe adverse perinatal outcome (0.4% [10/2,281] versus 1.0% [23/2,280]; relative risk [RR] 0.43 [95% confidence interval [CI] 0.21 to 0.91], p-value 0.027, risk difference [RD] -57/10,000 [95% CI -106/10,000 to -8/10,000], I2 0%). The number needed to treat (NNT) was 175 (95% CI 94 to 1,267). Perinatal deaths occurred in one (<0.1%) versus eight (0.4%) pregnancies (Peto odds ratio [OR] 0.21 [95% CI 0.06 to 0.78], p-value 0.019, RD -31/10,000, [95% CI -56/10,000 to -5/10,000], I2 0%, NNT 326, [95% CI 177 to 2,014]) and admission to a neonatal care unit ≥4 days occurred in 1.1% (24/2,280) versus 1.9% (46/2,273), (RR 0.52 [95% CI 0.32 to 0.85], p-value 0.009, RD -97/10,000 [95% CI -169/10,000 to -26/10,000], I2 0%, NNT 103 [95% CI 59 to 385]). There was no difference in the rate of cesarean delivery (10.5% versus 10.7%; RR 0.98, [95% CI 0.83 to 1.16], p-value 0.81) nor in other important perinatal, delivery, and maternal outcomes. MA on aggregate data showed similar results. Prespecified subgroup analyses for the primary outcome showed a significant difference in the treatment effect (p = 0.01 for interaction) for parity, but not for maternal age or BMI. The risk of severe adverse perinatal outcome was decreased for nulliparous women in the IOL group (0.3% [4/1,219] versus 1.6% [20/1,264]; RR 0.20 [95% CI 0.07 to 0.60], p-value 0.004, RD -127/10,000, [95% CI -204/10,000 to -50/10,000], I2 0%, NNT 79 [95% CI 49 to 201]) but not for multiparous women (0.6% [6/1,219] versus 0.3% [3/1,264]; RR 1.59 [95% CI 0.15 to 17.30], p-value 0.35, RD 27/10,000, [95% CI -29/10,000 to 84/10,000], I2 55%). A limitation of this IPD-MA was the risk of overestimation of the effect on perinatal mortality due to early stopping of the largest included trial for safety reasons after the advice of the Data and Safety Monitoring Board. Furthermore, only two RCTs were eligible for the IPD-MA; thus, the possibility to assess severe adverse neonatal outcomes with few events was limited.

CONCLUSIONS

In this study, we found that, overall, IOL at 41 weeks improved perinatal outcome compared with expectant management until 42 weeks without increasing the cesarean delivery rate. This benefit is shown only in nulliparous women, whereas for multiparous women, the incidence of mortality and morbidity was too low to demonstrate any effect. The magnitude of risk reduction of perinatal mortality remains uncertain. Women with pregnancies approaching 41 weeks should be informed on the risk differences according to parity so that they are able to make an informed choice for IOL at 41 weeks or expectant management until 42 weeks. Study Registration: PROSPERO CRD42020163174.

Antenatal awareness and obstetric outcomes in large fetuses: A retrospective evaluation

INTRODUCTION

There is currently no consensus on the management of large fetuses in order to minimize fetal complications. The aim of this study was to assess whether antenatal recognition of large-for-gestational age (LGA) reduced poor obstetric newborn outcomes in a hospital where expectant management was used.

MATERIAL AND METHODS

A retrospective cohort study was made of two delivery units at Karolinska University Hospital, Stockholm, Sweden, using expectant management of LGA. All deliveries > 37⁺⁰ weeks of gestation during an 8-year period (2002-2009) were included. The main outcome was severe adverse outcome, a composite variable including neonatal trauma (brachial plexus birth palsy [BPBP] and fractures) and asphyxic sequelae (severe asphyxia, cerebral damage, and fetal/infant death).

RESULTS

The study population consisted of 63,542 appropriate-for-gestational age (AGA) and 3,343 LGA pregnancies (of which 21 % were identified before delivery). Compared to AGA, LGA pregnancies showed a five-fold increased risk of neonatal trauma (OR 5.1, 95 % CI 4.0 - 6.4), but no differences were seen regarding asphyxic sequelae. LGA fetuses identified antenatally had adverse outcomes in 3.7 % of all cases, compared to 3.5 % where LGA was not identified (OR 1.07 95 % CI 0.7 - 1.7). When adjusted for newborn weight deviation, the OR was 0.96, 95 % CI 0.6 - 1.5. There was a three-fold higher risk (OR 3.0, 95 % CI 1.2 - 7.4) of neonatal trauma among non-identified LGA cases > 41⁺⁰ gestational weeks. A total of 81 % of those with LGA were identified after a week 41 routine ultrasound. Out of 68 cases with planned vaginal delivery and expected birth weight > 5000 g, 7.4 % suffered BPBP, representing a 31-fold increase in risk, compared to 0% BPBP among those delivered by elective caesarean section.

CONCLUSION

Antenatal awareness of LGA did not lower the risk of severe adverse outcomes in a unit using expectant management, but those identified postdate were at a lower risk of neonatal trauma. For every 14 fetuses with an expected birth weight > 5000 g delivered by cesarean section, one case of BPBP could be avoided.

Do premature and postterm birth increase the risk of epilepsy? An updated meta-analysis

BACKGROUND

Many studies have reported that premature birth is associated with a higher incidence of epilepsy, and postterm birth also increases the risk of epilepsy. The effects of different gestational ages (GAs) on epilepsy have become a research hotspot, but the findings of these studies remain controversial, and no systematic review has been performed until now.

OBJECTIVE

The aim of this study was to evaluate the impact of different GAs on the incidence of epilepsy.

DATA SOURCES

The main databases, including PubMed, Medline, Embase, Cochrane Library, and Web of Science, were searched using the terms "preterm/premature/early/postterm/postmature/late/delayed delivery/birth", "gestational age", and "epilepsy/seizure" for eligible studies published up to April 1, 2019. The search was limited to English-language articles.

STUDY SELECTION

Observational studies investigating the association between epilepsy and premature or postterm birth were included in this meta-analysis. We only selected studies that had clearly reported GA and the occurrence of epilepsy.

DATA EXTRACTION AND ANALYSIS

Two reviewers independently extracted the data. The quality of the included studies was examined in accordance with the Newcastle-Ottawa criteria, and the heterogeneity and publication bias were tested. We used sensitivity and subgroup analyses to determine the source of heterogeneity. A logistic randomized-effects model was used to assess the collected data when I² ≥ 50%.

MAIN OUTCOMES

The primary outcome was the odds ratio (OR) of epilepsy.

RESULTS

The research included eleven eligible studies with a total of 4,513,577 participants. Studies involving premature birth showed that the risk of epilepsy was 2.16 times higher in the premature birth group (<37 weeks) than in the full-term birth group (≥37 weeks) (OR [99% confidence interval [CI]] = 2.16 [1.80, 2.58]; P < 0.001). Those born before 32 weeks were associated with an increased occurrence of epilepsy when compared with those born at 32-36 weeks (OR [99% CI] = 2.73 [1.90, 3.94]; P < 0.001). However, the difference in the incidence of epilepsy between postterm children (41 weeks or more) and full-term children (37-40 weeks) was not statistically significant (OR [99% CI] = 1.05 [0.98, 1.12]; P = 0.067).

CONCLUSIONS

Preterm birth was closely associated with a higher risk of epilepsy throughout childhood that persisted into adulthood, and the association became stronger as GA decreased, while there was no significant difference in the risk of developing epilepsy between postterm and full-term offspring.

Management of late-term pregnancy in midwifery- and obstetrician-led care

Management of late-term pregnancy in midwifery- and obstetrician-led care.

BACKGROUND

Since there is no consensus regarding the optimal management in late-term pregnancies (≥41.0 weeks), we explored the variety of management strategies in late-term pregnancy in the Netherlands to identify the magnitude of this variety and the attitude towards late-term pregnancy.

METHODS

Two nationwide surveys amongst all midwifery practices (midwifery-led care) and all hospitals with an obstetric unit (obstetrician-led care) were performed with questions on timing, frequency and content of consultations/surveillance in late-term pregnancy and on timing of induction. Propositions about late-term pregnancy were assessed using Likert scale questions.

RESULTS

The response rate was 40% (203/511) in midwifery-led care and 92% (80/87) in obstetrician-led care. All obstetric units made regional protocols with their collaborating midwifery practices about management in late-term pregnancy. Most midwifery-led care practices (93%) refer low-risk women at least once for consultation in obstetrician-led care in late-term pregnancy. The content of consultations varies among hospitals. Membrane sweeping is performed more in midwifery-led care compared to obstetrician-led care (90% vs 31%, p < 0.001). Consultation at 41 weeks should be standard care according to 47% of midwifery-led care practices and 83% of obstetrician-led care units (p < 0.001). Induction of labour at 41.0 weeks is offered less often to women in midwifery-led care in comparison to obstetrician-led care (3% vs 21%, p < 0.001).

CONCLUSIONS

Substantial practice variation exists within and between midwifery-and obstetrician-led care in the Netherlands regarding timing, frequency and content of antenatal monitoring in late-term pregnancy and timing of labour induction. An evidence based interdisciplinary guideline will contribute to a higher level of uniformity in the management in late- term pregnancies.

Stillbirth and factor V Leiden - A regional based prospective evaluation

BACKGROUND

Approximately 10% of Swedes are carriers of coagulation factor V Leiden (FVL). It has been suggested that carriers are at an increased risk of stillbirth. We aimed to assess the risk of stillbirth in carriers of FVL as compared to non-carriers.

METHODS

A consecutive registration of all stillbirths from 2001 to 2015 in the whole Stockholm region has been performed. A FVL blood sample, an autopsy and histopathological examination of the placenta was scheduled to be offered all women with stillbirth. Main outcome was the difference in carriership of FVL between cases with live- vs. stillbirth. The primary cause of death was determined according to the Stockholm hierarchical classification of stillbirth.

RESULTS

The incidence of stillbirth was 3.6‰. Out of the 1392 cases of stillbirth occurring during the study period, FVL status was determined in 963 women. Of these 74 (7.7%) were carriers of FVL as compared to 8.1% in the control group (p = 0.6). A primary cause of death due to infection was twice as common among non-carriers compared to carriers of FVL (odds ratio [OR] = 2.3, 95% CI 1.08-4.8). In the whole study group, the prevalence of SGA was 14-fold increased among stillbirths as compared to live births (OR = 13.9, 95% CI 12.4-15.6).

CONCLUSION

Maternal FVL carriership was not related to an increased risk of stillbirth. However, a diagnosis of primary cause of death due to infection was less likely among FVL carriers.

Admission cardiotocography: A hospital based validation study

OBJECTIVE

Admission CTG is a short fetal heart rate (FHR) tracing recorded immediately at hospital admission to avoid unnecessary delay in action among pregnancies complicated by pre-existent fetal distress. There are different opinions regarding the value of the admission CTG, especially in low risk pregnancies.

STUDY DESIGN

A retrospective validation study from Karolinska University Hospital, Jan 2011 to June 2015 (total number of deliveries = 40,061). All women who underwent emergency cesarean section within one hour of admittance due to suspected fetal distress were identified. We assessed whether an admission CTG was performed, if it was beneficial for the decision to perform emergent cesarean delivery and if there were objective signs of fetal compromise or if it was performed unnecessarily. The main outcome was the benefit of the admission CTG in the decision to perform emergency cesarean delivery.

RESULTS

Eighty-eight cases (0.22%) fulfilled our inclusion criteria. Over 90% of these women (80/88) had objective evidence of compromised fetal well-being, i.e., indicating that emergent delivery was necessary. In 74% (54/73) of all cases was admission CTG determined to have been beneficial in the decision to perform cesarean delivery, equally effective of those classified as low- and high risk pregnancies before admission. In 28% (15/54) the CTG pathology was deemed difficult to identify by auscultation.

CONCLUSION

Admission CTG was deemed beneficial in 74% of both low- and high-risk pregnancies that were delivered by emergent cesarean section within one hour of admittance due to suspected fetal distress.