Put your weight behind it-Effect of body mass index on the active second stage of labour: A retrospective cohort study.

OBJECTIVE: To explore the duration of the active phase of the second stage of labour in relation to maternal pre-pregnant body mass index (BMI). DESIGN: Retrospective cohort study. SETTING: Labour wards of three Norwegian university hospitals, 2012-2019. POPULATION: Nulliparous and parous women without previous caesarean section with a live singleton fetus in cephalic presentation and spontaneous onset of labour, corresponding to the Ten Group Classification System (TGCS) group 1 and 3. METHODS: Women were stratified to BMI groups according to WHO classification, and estimated median duration of the active phase of the second stage of labour was calculated using survival analyses. Caesarean sections and operative vaginal deliveries during the active phase were censored. MAIN OUTCOME MEASURES: Estimated median duration of the active phase of second stage of labour. RESULTS: In all, 47 942 women were included in the survival analyses. Increasing BMI was associated with shorter estimated median duration of the active second stage in both TGCS groups. In TGCS group 1, the estimated median durations (interquartile range) were 44 (26-75), 43 (25-71), 39 (22-70), 33 (18-63), 34 (19-54) and 29 (16-56) minutes in BMI groups 1-6, respectively. In TGCS group 3, the corresponding values were 11 (6-19), 10 (6-17), 10 (6-16), 9 (5-15), 8 (5-13) and 7 (4-11) minutes. Increasing BMI remained associated with shorter estimated median duration in analyses stratified by oxytocin augmentation and epidural analgesia. CONCLUSION: Increasing BMI was associated with shorter estimated median duration of the active second stage of labour.

Induction of labor in breech presentations - a retrospective cohort study.

INTRODUCTION: There is limited evidence on the safety and outcome of induction of breech labor. In this study, we aimed to compare the outcomes of spontaneous and induced breech deliveries and to describe variations in induction rates. MATERIAL AND METHODS: This was a retrospective cohort study comprising 1054 singleton live fetuses in breech presentation at Trondheim University Hospital from 2012 to 2019. The main outcome was intrapartum cesarean section, and secondary outcomes were postpartum hemorrhage, anal sphincter ruptures, Apgar scores, pH in the umbilical artery, and metabolic acidosis. All data were obtained from the hospital birth journal. RESULTS: Induction of labor was performed in 127/606 (21.0%) women with planned vaginal birth. The frequency of intrapartum cesarean section was 48.0% for induced labor vs 45.7% for spontaneous labor (P = .64). We found no differences in the frequency of postpartum hemorrhage or anal sphincter ruptures between induced and spontaneous births. The median pH in the umbilical artery was significantly lower in neonates with induced labor compared with neonates with spontaneous labor (7.22 vs 7.25; P = .02). The frequency of pH <7.05 was 7.0% for induced labor vs 2.9% (P = .05) for spontaneous labor, but the frequency of pH <7.0 was not significantly different: 2.6% vs 0.8% (P = .14), respectively. Three neonates with planned vaginal birth had metabolic acidosis: two with spontaneous labors and one with induced labor. Three fetuses with planned vaginal birth died during labor: two with spontaneous onset of labor and one with induced labor. All three were extremely preterm: two were delivered in week 23 and one in week 25. We did not observe any significant trend in induction rates in either parous or nulliparous women. CONCLUSIONS: The induction rates were stable during the study period. We did not observe any significant difference in intrapartum cesarean section rates, in the frequency of pH <7.0 in the umbilical artery, or in the frequency of metabolic acidosis when comparing induced and spontaneous breech deliveries.

Infeksjon i operasjonsområdet.

BACKGROUND: All Norwegian hospitals must submit data to the Norwegian Surveillance System for Antibiotic Consumption and Healthcare-Associated Infections (NOIS) regarding surgical site infections following coronary artery bypass graft, caesarean section, hip arthroplasty, cholecystectomy and colonic surgery. The purpose of our study was to identify the proportion of patients undergoing surgery in 2016 who developed a surgical site infection, and the consequences in the form of prolonged postoperative hospitalisation, readmission or revision surgery. MATERIAL AND METHOD: All patients who underwent one of the five surgical procedures registered in NOIS in 2016 were included and followed up for 30 days after the surgery. The criteria set out by the European Centre for Disease Prevention and Control were used to define infections. RESULTS: From among the 31 401 patients included, a total of 1 225 surgical site infections were recorded. The incidence was highest following colonic surgery (10.9 %) and lowest following total hip arthroplasty (1.8 %). Median postoperative length of hospitalisation was three days for those with no infection, and six days for the 544 patients with a deep infection or an infection in an organ or cavity. The infections resulted in the need for revision surgery in 308 patients and readmission for 323 patients. INTERPRETATION: A total of 3.9 % of patients registered with a surgical procedure included in NOIS developed a surgical site infection. Consequences such as increased hospitalisation time, and more readmissions as well as revision procedures serve to highlight the importance of preventing such infections.

The Norwegian preeclampsia family cohort study: a new resource for investigating genetic aspects and heritability of preeclampsia and related phenotypes.

BACKGROUND: Preeclampsia is a major pregnancy complication without curative treatment available. A Norwegian Preeclampsia Family Cohort was established to provide a new resource for genetic and molecular studies aiming to improve the understanding of the complex pathophysiology of preeclampsia. METHODS: Participants were recruited from five Norwegian hospitals after diagnoses of preeclampsia registered in the Medical birth registry of Norway were verified according to the study's inclusion criteria. Detailed obstetric information and information on personal and family disease history focusing on cardiovascular health was collected. At attendance anthropometric measurements were registered and blood samples were drawn. The software package SPSS 19.0 for Windows was used to compute descriptive statistics such as mean and SD. P-values were computed based on t-test statistics for normally distributed variables. Nonparametrical methods (chi square) were used for categorical variables. RESULTS: A cohort consisting of 496 participants (355 females and 141 males) representing 137 families with increased occurrence of preeclampsia has been established, and blood samples are available for 477 participants. Descriptive analyses showed that about 60% of the index women's pregnancies with birth data registered were preeclamptic according to modern diagnosis criteria. We also found that about 41% of the index women experienced more than one preeclamptic pregnancy. In addition, the descriptive analyses confirmed that preeclamptic pregnancies are more often accompanied with delivery complications. CONCLUSION: The data and biological samples collected in this Norwegian Preeclampsia Family Cohort will provide an important basis for future research. Identification of preeclampsia susceptibility genes and new biomarkers may contribute to more efficient strategies to identify mothers "at risk" and contribute to development of novel preventative therapies.

Maternal deaths in Norway 2005-2009.

BACKGROUND: Norway has low maternal mortality, but such deaths are underreported even in high-income countries. Our goal was to identify the exact number of maternal deaths, the causes of death and the potential for improvement through medical care in Norway. MATERIAL AND METHOD: We traced maternal deaths in the period from 1 January 2005 to 31 December 2009 by linking the Medical Birth Registry and the Cause of Death Registry, supplemented with data from maternity clinics. We identified the cause of death and the lessons that could be learned by a meticulous review of each case. RESULTS: We found 26 maternal deaths during the period, 14 of which were due to direct causes and 12 to indirect causes. The maternal mortality ratio was 8.7/100,000 live births. Fourteen of the deaths were registered in official statistics. Of the 12 deaths that were not included in the statistics, 11 were found through matching the registers and one had been reported directly by the hospital. The most common causes of death were hypertensive disorders during pregnancy (n = 6), thromboembolism (n = 4) and mental illness (n = 4). None of the deaths due to thromboembolism appeared in official statistics. The same applied to nine of the 12 indirect maternal deaths. We found a potential for improved medical care in 14 of 26 cases. Half of these were deaths due to hypertensive disorders during pregnancy or thromboembolism. INTERPRETATION: Maternal death was considerably underreported in Norwegian official statistics during the period studied. Greater attention should be given to better blood-pressure treatment, stabilisation and timely delivery in the case of hypertension during pregnancy, and to screening for possible pulmonary embolism. The same applies to mental illness and internal medical disorders in pregnant women.

Validity of the diagnosis of pre-eclampsia in the Medical Birth Registry of Norway.

OBJECTIVE: Evaluating the validity of pre-eclampsia registration in the Medical Birth Registry of Norway (MBRN) according to both broader and restricted disease definitions. DESIGN: Retrospective nested cohort study. SETTING: Multicenter study. POPULATION: In this study, two cohorts of women with pre-eclamptic pregnancies registered in the MBRN were selected. Study group 1 contained 966 pregnancies from 1967 to 2002. Concomitant participation in the Nord-Trøndelag Health Study 2 was required. Study group 2 comprised 1138 pregnancies recorded in 1967-2005, examined as a pre-eclampsia biobank was established. METHODS: Diagnostic criteria vary. The broader criteria for pre-eclampsia, used by the MBRN, are one measurement of hypertension and proteinuria (Criterion A). Criteria used internationally today require two measurements of hypertension and proteinuria (Criterion B). The diagnostic validities in Study groups 1 and 2 were judged against medical records according to Criterion A and B, respectively. MAIN OUTCOME MEASURES: Positive predictive value (PPV) and trend analyses. RESULTS: The diagnosis was confirmed in 88.3% of pregnancies in Study group 1, and in 63.6% in Study group 2. PPV was high for Study group 1 throughout the period. For Study group 2, results improved significantly after 1986. CONCLUSIONS: This study ascertains high PPV of pre-eclampsia in the MBRN using broader traditional criteria, although the PPV decreases through assessment using restricted modern criteria. This illustrates how inclusion of direct measurements may improve registration of complex disorders defined by changing diagnostic criteria.

Induction of labor in twin pregnancies - A retrospective cohort study.

OBJECTIVE: To investigate outcomes in spontaneous and induced twin deliveries. Secondary aims were to study impact of delivery interval and breech presentation of the first twin. METHODS: This retrospective cohort study comprised 354 twin deliveries at a tertiary Norwegian hospital. Spontaneous labor onset and induction of labor were compared in women with planned vaginal delivery and gestational age ≥ 34 weeks. The main outcome was intrapartum cesarean section. Secondary outcomes were umbilical arterial pH and five-minute Apgar scores. RESULTS: Among the induced labors, 63/229 (27.5%) women underwent intrapartum cesarean section, compared to 45/125 (36%) in spontaneous labors (P = 0.10). Odds ratio for intrapartum cesarean section in induced labors was 0.65 (95% CI 0.40-1.04) after adjusting for maternal age and parity. Median umbilical arterial pH was significantly lower in the second twins in both spontaneous and induced labors, 7.28 (6.94-7.43) vs. 7.32 (7.16-7.42), and 7.27 (6.90-7.48) vs. 7.29 (7.08-7.45), respectively. pH < 7.00 rarely occurred. Second twins born after a delivery interval > 30 min had a significantly higher frequency of pH < 7.10 than those with a shorter interval, P < 0.01. No significant difference was found in frequency of pH < 7.10 between breech-presenting and cephalic-presenting first twins (P = 0.65). One unexpected intrapartum fetal death occurred after labor induction. CONCLUSION: Our results support spontaneous onset and induction of labor as safe. Intrapartum cesarean section rates did not differ significantly between spontaneous and induced labors. Delivery interval > 30 min was associated with a lower pH in the second twin.

Incidence and risk factors for obstetric anal sphincter ruptures, OASIS, following the introduction of preventive interventions. A retrospective cohort study from a Norwegian hospital 2012-2017.

OBJECTIVE: A decrease of obstetric anal sphincter injuries (OASIS) was observed after preventive interventions were implemented at a Norwegian university hospital. The aim was to investigate whether the improvement had sustained over the following years. MATERIALS AND METHODS: We performed a retrospective cohort study of 18 258 singleton vaginal cephalic births, ≥37 + 0 weeks of gestation during 2012-2017, examining data from the hospital's birth journals and separate registration forms. Interventions to prevent OASIS were implemented in 2011, and training in practical skills was repeated each year. MAIN OUTCOME MEASURES: The main outcome was OASIS (n = 377). RESULTS: Frequency of OASIS overall decreased from 3.6% prior to 2011 to 2.1% after the intervention and sustained at that level throughout the study period. A trend of fewer OASIS among spontaneous deliveries, decreasing from 2.1% to 1.2% (p = 0.01) was observed, but no trend was seen for instrumental deliveries (p = 0.37), where the incidence fluctuated between 4.0% and 9.3% with an average of 6.5%. Primiparity, increased maternal age and increased fetal head circumference were associated with more OASIS in spontaneous deliveries. In instrumental deliveries, primiparity, occiput posterior position and increased fetal head circumference were associated with more OASIS, whilst episiotomy was associated with fewer OASIS. CONCLUSION: The incidence of obstetric anal sphincter injuries maintained at a similar level of around 2.1% during the six following years after introducing preventive interventions. Regularly repetition and practical training seemed to be effective.

Elective induction of labor: A prospective observational study.

The aim of the present study was to assess indications for induction and describe the characteristics and delivery outcome in medical compared to non-medical/elective inductions. During a three-month period, 1663 term inductions were registered in 24 delivery units in Norway. Inclusion criteria were singleton pregnancies with cephalic presentation at gestational age 37+0 and beyond. Indications, pre-induction Bishop scores, mode of delivery and adverse maternal and fetal outcomes were registered, and compared between the medically indicated and elective induction groups. Ten percent of the inductions were elective, and the four most common indications were maternal request (35%), a previous negative delivery experience or difficult obstetric history (19%), maternal fatigue/tiredness (17%) and anxiety (15%). Nearly half of these inductions were performed at 39+0-40+6 weeks. There were fewer nulliparous women in the elective compared to the medically indicated induction group, 16% vs. 52% (p<0.05). The cesarean section rate in the elective induction group was 14% and 17% in the medically indicated group (14% vs. 17%, OR = 0.8, 95% CI 0.5-1.3). We found that one in ten inductions in Norway is performed without a strict medical indication and 86% of these inductions resulted in vaginal delivery.

OP006. A preeclampsia genome-wide linkage scan in norwegian families.

INTRODUCTION: Several maternal susceptibility loci for preeclampsia (PE) have been discovered amongst Icelandic, Australian/New Zealand, Dutch and Finnish family cohorts, implicating locus heterogeneity. Through candidate gene studies, allele-specific heterogeneity in different populations is also evident. It is therefore likely that numerous population specific PE susceptibility variants exist, differing in their effect size. Despite on-going efforts to identify susceptibility genes for PE, the causal genetic variants still remain obscure. OBJECTIVES: The aim of this study is to interrogate the genetic architecture of PE susceptibility by performing a genome-wide linkage scan in a novel familial cohort from Norway. METHODS: A total of 480 DNA samples from The Norwegian PE Family Biobank were genotyped at Genomic Core Facility at NTNU. Genome-wide genotyping was performed with the Infinium HumanExome BeadChip (>240,000 markers) (Illumina, USA) that delivers focused coverage of exonic regions of the human genome. RESULTS: A total of 137 families are represented with 222 women with a valid PE diagnosis (SBP⩾140mmHg DBP⩾90mmHg, ⩾2 measurements at least 4h apart with documented proteinuria at ⩾2 occasions occurring after 20weeks of pregnancy), 44 with self-reported PE and 72 women with a healthy pregnancy. The genotyping has just recently been completed with an average call rate of 99.96%. Data and statistical analysis is now underway using MERLIN, R and SOLAR. A description of the Norwegian PE familial cohort plus preliminary results will be presented at the Congress. CONCLUSION: To our knowledge this is the first SNP-based genome-wide linkage study on PE, and the first performed in a novel Norwegian PE family cohort. By using an approach focusing on functionally relevant markers we anticipate the identification of susceptibility loci that are of substantial importance for disease development.