More than time: travel time to the delivery ward and maternal outcomes - onset of labour, postpartum haemorrhage and obstetric anal sphincter injury.

BACKGROUND: Closing delivery units increases travel time for some women. Whether increased travel time is associated with maternal outcomes is important for understanding the consequences of such closures. Previous studies are limited in measuring travel time and restricted to the outcome of caesarean section. METHODS: Our population-based cohort includes data from the Swedish Pregnancy Register for women giving birth between 2014 and 2017 (N = 364,630). We estimated travel time from home to the delivery ward using coordinate pairs of actual addresses. The association between travel time and onset of labour was modelled using multinomial logistic regression, and logistic regression was used for the outcomes postpartum haemorrhage (PPH) and obstetric anal sphincter injury (OASIS). FINDINGS: Over three-quarters of women had ≤30 min travel time (median 13.9 min). Women who travelled ≥60 min arrived to care sooner and laboured there longer. Women with further to travel had increased adjusted odds ratio (aOR) of having an elective caesarean section (31-59 min aOR 1.11; 95% confidence interval [CI] 1.07-1.16; ≥60 min aOR 1.25; 95% CI 1.16-1.36) than spontaneous onset of labour. Women (at full term with spontaneous onset) living ≥60 min away had reduced odds of having a PPH (aOR 0.84; 95% CI 0.76-0.94) or OASIS (aOR 0.79; 95% CI 0.66-0.94). INTERPRETATION: Longer travel time increased the odds of elective caesarean section. Women with furthest to travel arrived sooner and spent more time in care; although they had a lower risk of PPH or OASIS, they also tended to be younger, have a higher body mass index and were Nordic born.

Postpartum haemorrhage trends in Sweden using the Robson ten group classification system: a population-based cohort study.

OBJECTIVE: To examine postpartum haemorrhage (PPH) trends in Sweden using the Robson classification system. DESIGN: Population-based cohort study. SETTING: Sweden. POPULATION: Deliveries in 2000-2016, classified as Robson groups 1-5 (singleton pregnancies in vertex presentation, from gestational weeks 37+0; n = 1 590 178). METHODS: We examined temporal trends in PPH between 2000 and 2016 overall, and within each Robson group, and performed logistic regression to examine the influence of changes in risk factors (maternal, comorbidity, obstetric practice and infant factors) over time. MAIN OUTCOME MEASURES: Postpartum haemorrhage, defined as an estimated blood loss of >1000 ml. RESULTS: The overall PPH rate increased from 5.4 to 7.3%, corresponding to a 37% (OR 1.37, 95% CI 1.32-1.42) increase over time. Rates varied between Robson groups, ranging from 4.5% in group 3 to 14.3% in group 4b. Increasing trends in PPH were found in all Robson groups except for groups 2b and 4b (prelabour caesarean deliveries). In the unstratified analysis, adjusting for maternal, comorbidity and obstetric practice factors slightly attenuated the risk of PPH in the later period (2013-2016), compared with the reference period (2000-2004; crude OR 1.26, 95% CI 1.24-1.29, adjusted OR 1.22, 95% CI 1.20-1.25). Within individual Robson groups, changes in risk factors did not explain increasing rates of PPH. CONCLUSIONS: Postpartum haemorrhage rates varied between Robson groups. Changes in risk factors could not explain the 37% increase in PPH for women in Robson groups 1-5 in Sweden, 2000-2016. TWEETABLE ABSTRACT: Changes in risk factors could not explain the increasing trend of PPH in Sweden, and rates of PPH varied widely between Robson groups.

Risk of pre-eclampsia after gastric bypass: a matched cohort study.

OBJECTIVE: To investigate whether gastric bypass before pregnancy is associated with reduced risk of pre-eclampsia. DESIGN: Nationwide matched cohort study. SETTING: Swedish national health care. POPULATION: A total of 843 667 singleton pregnancies without pre-pregnancy hypertension were identified in the Swedish Medical Birth Register between 2007 and 2014, of which 2930 had a history of gastric bypass and a pre-surgery weight available from the Scandinavian Obesity Surgery Registry. Two matched control groups (pre-surgery and early-pregnancy body mass index [BMI]) were propensity score matched separately for nulliparous and parous births, to post-gastric bypass pregnancies (npre-surgery-BMI = 2634:2634/nearly-pregnancy-BMI = 2766:2766) on pre-surgery/early-pregnancy BMI, diabetes status (pre-surgery/pre-conception), maternal age, early-pregnancy smoking status, educational level, height, country of birth, delivery year and history of pre-eclampsia. MAIN OUTCOME MEASURES: Pre-eclampsia categorised into any, preterm onset (<37+0 weeks) and term onset (≥37+0 weeks). RESULTS: In post-gastric bypass pregnancies, mean pre-surgery BMI was 42.9 kg/m2 and mean BMI loss between surgery and early pregnancy was 14.0 kg/m2 (39 kg). Post-gastric bypass pregnancies had lower risk of pre-eclampsia compared with pre-surgery BMI-matched controls (1.7 versus 9.7 per 100 pregnancies; hazard ratio [HR] 0.21, 95% CI 0.15-0.28) and early-pregnancy BMI-matched controls (1.9 versus 5.0 per 100 pregnancies; HR 0.44, 95% CI 0.33-0.60). Although relative risks for pre-eclampsia for post-gastric bypass pregnancies versus pre-surgery matched controls was similar, absolute risk differences (RD) were significantly greater for nulliparous women (RD -13.6 per 100 pregnancies, 95% CI -16.1 to -11.2) versus parous women (RD -4.4 per 100 pregnancies, 95% CI -5.7 to -3.1). CONCLUSION: We found that gastric bypass was associated with lower risk of pre-eclampsia, with the largest absolute risk reduction among nulliparous women. TWEETABLE ABSTRACT: In this large study including two comparison groups matched for pre-surgery or early-pregnancy BMI, gastric bypass was associated with lower risk of pre-eclampsia.

Pregnancy and risk of COVID-19: a Norwegian registry-linkage study.

OBJECTIVE: To compare the risk of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and contact with specialist healthcare services for coronavirus disease 2019 (COVID-19) between pregnant and non-pregnant women. POPULATION OR SAMPLE: All women ages 15-45 living in Norway on 1 March 2020 (n = 1 033 699). METHODS: We linked information from the national birth, patient, communicable diseases and education databases using unique national identifiers. MAIN OUTCOME MEASURE: We estimated hazard ratios (HR) among pregnant compared to non-pregnant women of having a positive test for SARS-CoV-2, a diagnosis of COVID-19 in specialist healthcare, or hospitalisation with COVID-19 using Cox regression. Multivariable analyses adjusted for age, marital status, education, income, country of birth and underlying medical conditions. RESULTS: Pregnant women were not more likely to be tested for or to a have a positive SARS-CoV-2 test (adjusted HR 0.99; 95% CI 0.92-1.07). Pregnant women had higher risk of hospitalisation with COVID-19 (HR 4.70, 95% CI 3.51-6.30) and any type of specialist care for COVID-19 (HR 3.46, 95% CI 2.89-4.14). Pregnant women born outside Scandinavia were less likely to be tested, and at higher risk of a positive test (HR 2.37, 95% CI 2.51-8.87). Compared with pregnant Scandinavian-born women, pregnant women with minority background had a higher risk of hospitalisation with COVID-19 (HR 4.72, 95% CI 2.51-8.87). CONCLUSION: Pregnant women were not more likely to be infected with SARS-CoV-2. Still, pregnant women with COVID-19, especially those born outside of Scandinavia, were more likely to be hospitalised. TWEETABLE ABSTRACT: Pregnant women are at increased risk of hospitalisation for COVID-19.

SARS-CoV-2 and pregnancy outcomes under universal and non-universal testing in Sweden: register-based nationwide cohort study.

OBJECTIVE: To assess associations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and pregnancy outcomes considering testing policy and test-positivity-to-delivery interval. DESIGN: Nationwide cohort study. SETTING: Sweden. POPULATION: From the Pregnancy-Register we identified 88 593 singleton births, 11 March 2020-31 January 2021, linked to data on SARS-CoV-2-positivity from the Public Health Agency, and information on neonatal care admission from the Neonatal Quality Register. Adjusted odds ratios (aORs) were estimated stratified by testing-policy and test-positivity-to-delivery interval. MAIN OUTCOME MEASURES: Five-minute Apgar score, neonatal care admission, stillbirth and preterm birth. RESULTS: During pregnancy, SARS-CoV-2 test-positivity was 5.4% (794/14 665) under universal testing and 1.9% (1402/73 928) under non-universal testing. There were generally lower risks associated with SARS-CoV-2 under universal than non-universal testing. In women testing positive >10 days from delivery, generally no significant differences in risk were observed under either testing policy. Neonatal care admission was more common (15.3% versus 8.0%; aOR 2.24, 95% CI 1.62-3.11) in women testing positive ≤10 days before delivery under universal testing. There was no significant association with 5-minute Apgar score below 7 (1.0% versus 1.7%; aOR 0.64, 95% CI 0.24-1.72) or stillbirth (0.3% versus 0.4%; aOR 0.72, 95% CI 0.10-5.20). Compared with term births (2.1%), test-positivity was higher in medically indicated preterm birth (5.7%; aOR 2.70, 95% CI 1.60-4.58) but not significantly increased in spontaneous preterm birth (2.3%; aOR 1.12, 95% CI 0.62-2.02). CONCLUSIONS: Testing policy and timing of test-positivity impact associations between SARS-CoV-2-positivity and pregnancy outcomes. Under non-universal testing, women with complications near delivery are more likely to be tested than women without complications, thereby inflating any association with adverse pregnancy outcomes compared with findings under universal testing. TWEETABLE ABSTRACT: Testing policy and time from SARS-CoV-2 infection to delivery influence the association with pregnancy outcomes.

Maternal and infant pregnancy outcomes in women with psoriatic arthritis: a Swedish nationwide cohort study.

OBJECTIVE: Studies on pregnancy outcomes in psoriatic arthritis (PsA) are scarce and typically of small size. Available studies have reported conflicting results. The aim of this study was to describe maternal and infant pregnancy outcomes among women with PsA compared with women without PsA. DESIGN: Nationwide cohort study. SETTING: Nationwide Swedish registers. POPULATION: A total of 41 485 singleton pregnancies in 1997-2014, of which 541 pregnancies were identified with PsA exposure and 40 944 pregnancies were unexposed. METHODS: By linkage of national health and population register data, we obtained information on individual pregnancies and compared outcomes among pregnancies with PsA and non-PsA pregnancies. Relative risks were estimated by odds ratios (ORs) with 95% CIs using a generalised linear regression model with generalised estimating equations. Adjustments were made for maternal factors and calendar year of birth. MAIN OUTCOME MEASURES: Maternal and infant pregnancy outcomes. RESULTS: Pregnancies to women with PsA had increased risks of preterm birth (adjusted OR 1.63; 95% CI 1.17-2.28), elective and emergency caesarean deliveries (adjusted OR 1.47; 95% CI 1.10-1.97 and adjusted OR 1.43; 95% CI 1.08-1.88, respectively) compared with non-PsA pregnancies. No increased risks were observed for pre-eclampsia, stillbirth or other infant outcomes apart from preterm birth. CONCLUSION: The majority of women with PsA have uneventful pregnancies with respect to adverse outcomes. In the present study, we found increased risks of preterm birth and caesarean delivery compared with non-PsA pregnancies. TWEETABLE ABSTRACT: Women with psoriatic arthritis have uneventful pregnancies but are at increased risk of preterm birth and caesarean delivery.

Prenatal exposures and birth indices, and subsequent risk of polycystic ovary syndrome: a national registry-based cohort study.

OBJECTIVE: To study the associations between prenatal exposures and risk of developing polycystic ovary syndrome (PCOS). DESIGN: National registry-based cohort study. SETTING: Sweden. POPULATION: Girls born in Sweden during the years 1982-1995 (n = 681 123). METHODS: The girls were followed until the year 2010 for a diagnosis of PCOS. We estimated the associations between maternal body mass index (BMI), smoking, and size at birth with the risk of developing a PCOS diagnosis. Risks were calculated by adjusted hazard ratio (aHR) and 95% confidence intervals (95% CIs). MAIN OUTCOME MEASURES: A diagnosis of PCOS at 15 years of age or later. RESULTS: During the follow-up period 3738 girls were diagnosed with PCOS (0.54%). Girls with mothers who were overweight or obese had 1.5-2.0 times higher risk of PCOS (aHR 1.52, 95% CI 1.36-1.70; aHR 1.97, 95% CI 1.61-2.41, respectively), compared with girls born to mothers of normal weight. The risk of PCOS was increased if the mother smoked during pregnancy (1-9 cigarettes/day, aHR 1.31, 95% CI 1.18-1.47; ≥10 cigarettes/day, aHR 1.44, 95% CI 1.27-1.64). Being born small for gestational age (SGA) was associated with a later diagnosis of PCOS in crude estimates, but the association was not significant after adjusting for maternal factors. CONCLUSIONS: Maternal smoking and increased BMI appear to increase the risk of PCOS in offspring. The association between SGA and the development of PCOS appears to be mediated by maternal factors. TWEETABLE ABSTRACT: Smoking during pregnancy and high maternal BMI are associated with PCOS diagnosis in the offspring.

Prepregnancy maternal body mass index and venous thromboembolism: a population-based cohort study.

OBJECTIVE: To assess the relation between maternal body mass index (BMI) and pregnancy-related venous thromboembolism (VTE). DESIGN: Cohort study. SETTING AND POPULATION: A total of 2 449 133 women with singleton pregnancies who underwent delivery hospitalisation in California between 2008 and 2012. METHODS: Association of pre-pregnancy BMI and the risk of an antepartum and postpartum VTE was examined using logistic regression, with normal BMI as reference. MAIN OUTCOME MEASURES: Antepartum and postpartum VTE-related hospitalisation. RESULTS: The prevalence of antepartum and postpartum VTE increased with increasing BMI (antepartum: 2.3, 3.0, 3.8, 4.2, 4.7, and 10.6 per 10 000 women for underweight, normal BMI, overweight, obesity class I, II, and III, respectively, P < 0.001; postpartum: 2.0, 3.1, 3.9, 5.6, 9.0, and 13.2 per 10 000 women, P < 0.01). The adjusted odds of antepartum and postpartum VTE increased progressively with increasing BMI, with obesity class III women having the highest risk of pregnancy-related VTE compared with normal BMI women: adjusted odds ratio for antepartum VTE: 2.9; 95% CI 2.2-3.8 and adjusted odds ratio for postpartum VTE: 3.6; 95% CI 2.9-4.6. CONCLUSIONS: Our findings clearly demonstrate an increasing risk of pregnancy-related VTE with increasing BMI. TWEETABLE ABSTRACT: Obesity was associated with increased odds of antepartum and postpartum venous thromboembolism.

Pregnancy weight gain by gestational age and stillbirth: a population-based cohort study.

OBJECTIVE: To study the association between total and early pregnancy (<22 completed weeks) weight gain and risk of stillbirth, stratified by early-pregnancy body mass index (BMI). DESIGN: Population-based cohort study. SETTING: Stockholm-Gotland Region, Sweden. POPULATION: Pregnant women with singleton births (n = 160 560). METHODS: Pregnancy weight gain was standardised into gestational age-specific z-scores. For analyses of total pregnancy weight gain, a matched design with an incidence density sampling approach was used. Findings were also contrasted with current Institute of Medicine (IOM) weight gain recommendations. MAIN OUTCOME MEASURES: Stillbirth defined as fetal death at ≥22 completed weeks of gestation. RESULTS: For all BMI categories, there was no statistical association between total or early pregnancy weight gain and stillbirth within the range of a weight gain z-score of -2.0 SD to +2.0 SD. Among normal-weight women, the adjusted odds ratio of stillbirth for lower (-2.0 to -1.0 SD) and higher (+1.0 to +1.9 SD) total weight gain was 0.85 (95% CI; 0.48-1.49) and 1.03 (0.60-1.77), respectively, as compared with the reference category. Further, there were no associations between total or early pregnancy weight gain and stillbirth within the range of weight gain currently recommended by the IOM. For the majority of the BMI categories, the point estimates at the extremes of weight gain values (<-2.0SD and ≥2.0 SD) suggested protective effects of low weight gain and increased risks of high weight gain, but estimates were imprecise and not statistically significant. CONCLUSION: We found no associations between total or early pregnancy weight gain and stillbirth across the range of weight gain experienced by most women. TWEETABLE ABSTRACT: There was no association between weight gain during pregnancy and stillbirth among most women.

A policy of routine umbilical cord blood gas analysis decreased missing samples from high-risk births.

AIM: This study compared obstetric units practicing routine or selective umbilical cord blood gas analysis, with respect to the risk of missing samples in high-risk deliveries and in infants with birth asphyxia. METHODS: This was a Swedish population-based cohort study that used register data for 155 235 deliveries of live singleton infants between 2008 and 2014. Risk ratios and 95% confidence intervals were calculated to estimate the association between routine and selective umbilical cord blood gas sampling strategies and the risk of missing samples. RESULTS: Selective sampling increased the risk ratios when routine sampling was used as the reference, with a value of 1.0, and these were significant in high-risk deliveries and birth asphyxia. The risk ratios for selective sampling were large-for-gestational age (9.07), preterm delivery at up to 36 weeks of gestation (8.24), small-for-gestational age (7.94), two or more foetal scalp blood samples (5.96), an Apgar score of less than seven at one minute (2.36), emergency Caesarean section (1.67) and instrumental vaginal delivery (1.24). CONCLUSION: Compared with routine sampling, selective umbilical cord blood gas sampling significantly increased the risks of missing samples in high-risk deliveries and in infants with birth asphyxia.

Prolonged second stage of labour, maternal infectious disease, urinary retention and other complications in the early postpartum period.

OBJECTIVE: To study the association between duration of second stage of labour and risks of maternal complications (infection, urinary retention, haematoma or ruptured sutures) in the early postpartum period. DESIGN: Population-based cohort study. SETTING AND SAMPLE: We included 72 593 mothers with singleton vaginal deliveries at ≥37 weeks of gestation in cephalic presentation, using the obstetric database from the Stockholm-Gotland region in Sweden, 2008-12. METHODS: Logistic regression analysis. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated and adjustments were made for maternal age, body mass index, height, smoking, cohabitation, gestational age, labour induction, epidural analgesia and oxytocin augmentation. RESULTS: Rates of any complication varied by parity from 7.3% in parous women with previous caesarean section, 4.8% in primiparas and 1.7% in parous women with no previous caesarean section. Compared with a second stage <1 hour, the adjusted ORs for any complication (95% CI) in primiparas were for 1 to <2 hours 1.28 (1.11-1.47); 2 to <3 hours 1.54 (1.32-1.79), 3 to <4 hours 1.63 (1.38-1.93) and ≥4 hours 2.08 (1.74-2.49). The corresponding adjusted ORs for parous women without previous caesarean were 2.27 (1.78-2.90), 2.97 (2.09-4.22), 3.65 (2.25-5.94) and 3.16 (1.44-6.94), respectively. The adjusted ORs for women with previous caesarean were for 1 to <2 hours 1.62 (1.13-2.32); 2 to <3 hours 1.56 (1.00-2.43), 3 to <4 hours 2.42 (1.52-3.87), and ≥4 hours 2.31 (1.25-4.24). CONCLUSIONS: Risks of maternal complications in the postpartum period increase with duration of second stage of labour also after accounting for maternal, pregnancy and delivery characteristics. Special attention has to be given to parous women with previous caesarean deliveries.

Pregnancy and perinatal outcomes in women with polycystic ovary syndrome and twin births: a population-based cohort study.

OBJECTIVE: To investigate pregnancy and perinatal outcomes in twin births among women with and without polycystic ovary syndrome (PCOS) diagnosis. DESIGN: Population-based cohort study. SETTING: Sweden. POPULATION: We identified 20,965 women with twin births between 1995 and 2009 of whom 226 had a PCOS diagnosis through linkage between the Swedish Medical Birth Register and the Swedish National Patient Register. METHODS: Calculating risk ratios (RR) with 95% confidence intervals (CI) using a log-binomial regression model and hazard ratios (HR) with 95% CI for preterm birth. MAIN OUTCOME MEASURES: Preterm birth, low birthweight, caesarean section, pre-eclampsia, Apgar score <7 at 5 minutes and perinatal mortality. RESULTS: PCOS diagnosis in twin pregnancy was associated with increased risk of preterm delivery (51% versus 43%, RR 1.18 [95% CI 1.03-1.37]), particularly spontaneous preterm delivery (37% versus 28%; RR 1.30 [95% CI 1.09-1.55]) and very preterm birth (<32 weeks) (14% versus 8%, RR 1.62 [95% CI 1.10-2.37]). Twins of PCOS mothers had more often low birthweight (48% versus 39%, adjusted RR 1.40 [95% CI 1.09-1.80]). This difference disappeared when adjusting for gestational age. No risk difference was found for caesarean section, pre-eclampsia, low 5-minute Apgar score or perinatal mortality. CONCLUSIONS: The risk of preterm delivery in twin pregnancies is increased by having a PCOS diagnosis. This should be considered in risk estimation and antenatal follow-up of twin pregnancies.

Use of antidepressants and association with elective termination of pregnancy: population based case-control study.

OBJECTIVE: To assess whether the use of selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, mirtazapine, venlafaxine or other antidepressants is associated with late elective termination of pregnancy. DESIGN: Case-control study using data from national registers. SETTING: Denmark, Finland, and Norway during the period 1996-2007. POPULATION: A total of 14,902 women were included as cases and 148,929 women were included as controls. METHODS: Cases were women with elective termination of pregnancy at 12-23 weeks of gestation. Controls continued their pregnancy and were matched with cases on key factors. MAIN OUTCOME MEASURES: Association between antidepressant use during pregnancy and elective termination of pregnancy at 12-23 weeks of gestation for fetal anomalies, or for maternal ill health or socio-economic disadvantage. RESULTS: At least one prescription of antidepressants was filled by 3.7% of the cases and 2.2% of the controls. Use of any type of antidepressant was associated with elective termination of pregnancy for maternal ill health or socio-economic disadvantage (odds ratio, OR 2.3; 95% confidence interval, 95% CI 2.0-2.5). Elective termination of pregnancy for fetal anomalies was associated with the use of mirtazapine (OR 2.2, 95% CI 1.1-4.5). There was no association between the use of any of the other antidepressants and elective termination of pregnancy for fetal anomalies. CONCLUSION: The use of any type of antidepressants was associated with elective termination of pregnancy at 12-23 weeks for maternal ill health or socio-economic disadvantage, but not with terminations for fetal anomalies. Further studies need to confirm the findings concerning mirtazapine and termination of pregnancy for fetal anomalies.

Retained placenta is associated with pre-eclampsia, stillbirth, giving birth to a small-for-gestational-age infant, and spontaneous preterm birth: a national register-based study.

OBJECTIVE: To evaluate whether defective placentation disorders, i.e. pre-eclampsia, stillbirth, small for gestational age (SGA), and spontaneous preterm birth, are associated with risk of retained placenta. DESIGN: Population-based cohort study. SETTING: Sweden. POPULATION: Primiparous women in Sweden with singleton vaginal deliveries between 1997 and 2009 at 32-41 weeks of gestation (n = 386,607), without placental abruption or infants with congenital malformations. METHODS: Risks were calculated as odds ratios (ORs) by unconditional logistic regression with 95% confidence intervals (95% CIs) after adjustments for maternal, delivery, and infant characteristics. MAIN OUTCOME MEASURE: Retained placenta, defined by the presence of both a diagnostic code (of retained placenta) and a procedure code (for the manual removal of the placenta). RESULTS: The overall rate of retained placenta was 2.17%. The risk of retained placenta was increased for women with pre-eclampsia (adjusted OR, aOR, 1.37, 95% CI 1.21-1.54), stillbirth (aOR 1.71, 95% CI 1.28-2.29), SGA birth (aOR 1.47, 95% CI 1.28-1.70), and spontaneous preterm birth (32-34 weeks of gestation, aOR 2.35, 95% CI 1.97-2.81; 35-36 weeks of gestation, aOR 1.55, 95% CI 1.37-1.75). The risk was further increased for women with preterm pre-eclampsia (aOR 1.69, 95% CI 1.25-2.28) and preterm SGA birth (aOR 2.19, 95% CI 1.42-3.38). There was no association between preterm stillbirth (aOR 1.10, 95% CI 0.63-1.92) and retained placenta, but the exposed group comprised only 15 cases. CONCLUSIONS: Defective placentation disorders are associated with an increased risk of retained placenta. Whether these relationships indicate a common pathophysiology remains to be investigated.

Changes in snuff and smoking habits in Swedish pregnant women and risk for small for gestational age births.

OBJECTIVE: To examine associations between antenatal exposure to Swedish oral moist snuff (which includes essentially only nicotine) and to smoking and risks of small-for-gestational-age (SGA) births and to compare risks among women who stopped or continued using snuff or smoking during pregnancy. DESIGN: Population-based cohort study. SETTING: Sweden. POPULATION: All live singleton births in Sweden 1999-2010. METHODS: Odds ratios (OR) with 95% confidence intervals (CI) were calculated using multiple logistic regression analysis. MAIN OUTCOME MEASURES: SGA birth, also stratified into preterm (≤36 weeks of gestation) and term (≥37 weeks of gestation) SGA births. RESULTS: Compared with non-tobacco users in early pregnancy, snuff users and above all smokers in early pregnancy had increased risks of SGA births: adjusted ORs (95% CI) were 1.26 (1.09-1.46) and 2.55 (2.43-2.67), respectively). Snuff use had, if anything, a stronger association with preterm SGA than term SGA, whereas the opposite was true for smoking. Compared with non-tobacco users, women who stopped using snuff before their first visit to antenatal care had no increased risks of preterm or term SGA, and women who stopped using snuff later during pregnancy had no increased risk of term SGA. Smoking cessation early in pregnancy was associated with a larger reduction in risk than smoking cessation later in pregnancy. CONCLUSIONS: As both smoking and snuff use influence risk of SGA, both nicotine but above all tobacco combustion products are involved in the mechanisms by which maternal smoking increases the risk of SGA.

Hyperemesis gravidarum and risks of placental dysfunction disorders: a population-based cohort study.

OBJECTIVE: To study whether pregnancies complicated by hyperemesis gravidarum in the first (<12 weeks) or second (12-21 weeks) trimester are associated with placental dysfunction disorders. DESIGN: Population-based cohort study. SETTING: Sweden. POPULATION: All pregnancies in the Swedish Medical Birth Register estimated to have started on 1 January 1997 or later and ended in a single birth on 31 December 2009 or earlier (n = 1 156 050). METHODS: Odds ratios with 95% confidence intervals were estimated for placental dysfunction disorders in women with an inpatient diagnosis of hyperemesis gravidarum, using women without inpatient diagnosis of hyperemesis gravidarum as reference. Risks were adjusted for maternal age, parity, body mass index, height, smoking, cohabitation with the infant's father, infant's sex, mother's country of birth, education, presence of hyperthyreosis, pregestational diabetes mellitus, chronic hypertension and year of infant birth. MAIN OUTCOME MEASURES: Placental dysfunction disorders, i.e. pre-eclampsia, placental abruption, stillbirth and small for gestational age (SGA). RESULTS: Women with hyperemesis gravidarum in the first trimester had only a slightly increased risk of pre-eclampsia. Women with hyperemesis gravidarum with first admission in the second trimester had a more than doubled risk of preterm (<37 weeks) pre-eclampsia, a threefold increased risk of placental abruption and a 39% increased risk of an SGA birth (adjusted odds ratios [95% confidence intervals] were: 2.09 [1.38-3.16], 3.07 [1.88-5.00] and 1.39 [1.06-1.83], respectively). CONCLUSIONS: There is an association between hyperemesis gravidarum and placental dysfunction disorders, which is especially strong for women with hyperemesis gravidarum in the second trimester.

Intrahepatic cholestasis of pregnancy and associated adverse pregnancy and fetal outcomes: a 12-year population-based cohort study.

OBJECTIVE: To determine the risk for adverse pregnancy and fetal outcomes in intrahepatic cholestasis of pregnancy (ICP). DESIGN: Population-based cohort study. SETTING: Swedish Medical Birth Register (MBR) 1997-2009. POPULATION: A total of 1,213,668 singleton deliveries. METHODS: Linkage of Hospital Discharge Register for exposure (ICP; n=5,477) with MBR for covariates. MAIN OUTCOME MEASURES: Gestational diabetes, pre-eclampsia, prematurity, and stillbirth. RESULTS: Intrahepatic cholestasis (ICP) was diagnosed in 0.32-0.58% of all pregnancies, with an increasing trend until 2005 (P<0.0001). Compared with women who did not have ICP, women with ICP were more likely to have gestational diabetes (adjusted odds ratio, aOR, 2.81; 95% CI 2.32-3.41) and pre-eclampsia (aOR 2.62, 95% CI 2.32-2.78). Women with ICP were also more likely to have spontaneous (aOR 1.60, 95% CI 1.47-1.93) and iatrogenic (aOR 5.95, 95% CI 5.23-6.60) preterm delivery, with increased rates of induction of labour (aOR 11.76, 95% CI 11.04-11.62). However, this actively managed cohort of ICP cases was not at increased risk of stillbirth (aOR 0.92, 95% CI 0.52-1.62). Infants in ICP deliveries were more likely to have a low (<7) 5-minute Apgar score (aOR 1.45, 95% CI 1.14-1.85) and be large for gestational age at birth (aOR 2.27, 95% CI 2.02-2.55). CONCLUSIONS: Over time, a greater proportion of Swedish pregnant women have received a diagnosis of ICP, probably because of an increased awareness of the disorder. Our data confirm an increased risk of preterm delivery, but not of stillbirth, in actively managed ICP. The high rates of gestational diabetes and pre-eclampsia are new findings, and need to be considered in the management of ICP pregnancies.

Maternal and pregnancy predictive risk factors for having a compensated maternal injury claim: a Swedish nationwide cohort study.

To describe trends and identify maternal and pregnancy predictive risk factors for having a compensated claim for a maternal injury during delivery, as a proxy for having received suboptimal care. This nationwide retrospective cohort study included 1 754 869 births in Sweden between 2000 and 2016, including 4488 maternal injury claims filed with The National Swedish Patient Insurance Company (Löf), of which 1637 were compensated. Descriptive statistics on maternal and pregnancy characteristics, trends in filed/compensated claims over time, and distribution of compensated claims by clinical classification are presented. Characteristics associated with suboptimal care were identified using multivariable logistic regression, with mutual adjustment in the final model. Compensated claims were sorted into 14 clinical classifications (ICD-10 codes for main condition, injury, and causality). Overall, there was a two-fold increase in filed claims from 2000 to 2016, peaking in 2014. The rate of compensated claims only increased marginally, and 36.5% of filed claims were deemed avoidable. Perineal and pelvic floor injuries, as well as medical and diagnostic errors, were responsible for the majority of compensated claims. Women with a previous caesarean section, post term delivery, chronic or gestational disease, > 13 antenatal visits, or a multiple pregnancy had increased risk of having a compensated claim for a maternal injury during delivery. Understanding the risk factors for having a compensated maternal injury claim may guide health workers and maternity wards in improving the quality and organisation of care to reduce the risk of childbirth related injuries.

Labour dystocia--risk of recurrence and instrumental delivery in following labour--a population-based cohort study.

OBJECTIVE: To investigate risk of recurrence of labour dystocia and mode of delivery in second labour after taking first labour and fetal and maternal characteristics into account. DESIGN: A population-based cohort study. SETTING: The Swedish Medical Birth Register from 1992 to 2006. POPULATION: A total of 239 953 women who gave birth to their first and second singleton infants in cephalic presentation at ≥ 37 weeks of gestation with spontaneous onset of labour. METHODS: We used logistic regression analysis to estimate crude and adjusted odds ratios. MAIN OUTCOME MEASURES: Labour dystocia and mode of delivery in second labour. RESULTS: Overall labour dystocia affected only 12% of women with previous dystocia. Regardless of mode of first delivery, rates of dystocia in the second labour were higher in women with than without previous dystocia, but were more pronounced in women with previous caesarean section (34%). Analyses with risk score groups for dystocia (risk factors were long interpregnancy interval, maternal age ≥ 35 years, obesity, short maternal stature, not cohabiting and post-term pregnancy) showed that risk of instrumental delivery in second labour increased with previous dystocia and increasing risk score. Among women with trial of labour after caesarean section with previous dystocia and a risk score of 3 or more, 66% had a vaginal instrumental or caesarean delivery (17 and 49%, respectively). In women with trial of labour after caesarean section without previous dystocia and a risk score of 0, corresponding risk was 32% (14 and 18%, respectively). CONCLUSION: Previous labour dystocia increases the risk of dystocia in subsequent delivery. Taking first labour and fetal and maternal characteristics into account is important in the risk assessments for dystocia and instrumental delivery in second labour.

Tick-borne encephalitis in pregnant women: A mini narrative review.

Tick-borne encephalitis (TBE) incidence has been increasing in Europe the last decades, but very few cases in pregnant women have been described. We present two cases and describe the serology of both mother and infant at the time of diagnosis and delivery, as well as at months 3, 6, 9, and 12 of follow-up. In both cases, pregnancies and infants developed normally. The mothers had moderate-to severe symptoms of TBE and were positive for IgM and IgG at the time of diagnosis, and throughout the follow up period whilst both infants were PCR- and IgM-negative and positive for IgG during their first months in life. Declining IgG titres were seen in the infants during follow-up until they became negative at the age of nine months. TBE IgG was vertically transmitted in these two cases of infants born to TBE-infected mothers.