It is well known that smoking and pregnancy induced hypertension (PIH) are associated with decreased fetal growth. It has been reported that in preeclampsia the fetal growth deficit attributable to ...smoking is higher, which has been contradicted in other studies. We therefore evaluated the effects on fetal growth of early- and late onset PIH and chronic hypertension and how cigarette smoking modify these effects. We also quantified the proportion of small for gestational age (SGA) cases attributable to PIH, chronic hypertension, and smoking.
Population-based study based on record of 215598 singleton pregnancies from the Medical Birth Registry of Norway.
In severe preeclampsia, mild preeclampsia, transient hypertension, and normotension in term birth, odds ratios (ORs) of SGA in smokers compared with non-smokers were 1.4 (95% confidence interval 0.9, 2.2), 1.6 (1.3, 1.9), 2.3 (1.8, 3.1), and 2.0 (1.9, 2.1), respectively. For preterm births, corresponding ORs were 1.3 (0.9, 2.0), 1.8 (1.1, 3.0), 4.1 (1.9, 9.0), and 1.7 (1.4, 2.0), respectively. The effect of early onset PIH was stronger than that in term births, while the effect of smoking was equal in preterm and term newborns. Only in non-smokers who delivered at term, the rates of SGA significantly increased with the severity of PIH (ORs = 1.3 (1.1, 1.5), 1.8 (1.7, 2.0), and 2.5 (2.2, 3.0) for transient hypertension, mild-, and severe preeclampsia, respectively). The combined effects of smoking and hypertension were generally not synergistic. The effect of smoking was not stronger in women who had chronic hypertension. Nor were the effects of chronic hypertension stronger in smokers. PIH explained 21.9 and 2.5% of preterm and term cases of SGA, respectively, while smoking explained 12% of SGA cases.
The effects of hypertensive disorder and smoking were generally not synergistic, which suggest that they may exert their main actions on separate sites or work through separate mechanisms within or outside the placenta. If smoking were eliminated in pregnant women, the number of SGA cases would be reduced by 12%.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background. The purpose of the present study was to validate the registration of obstetric sphincter tears in 2 registers, the Medical Birth Registry of Norway MBRN and Patient Administration System ...PAS. Methods. A retrospective cohort study of all obstetric sphincter tears that occurred in our department in 1990-1992 and 2000-2002 was performed. The case records of all patients registered either in MBRN, PAS or the birth logs were compared with the information in the medical records, which constituted the 'golden standard'. Results. The incidence of obstetric sphincter tears in 1990-1992 was 5.8% (774/13381), 5.6% (745/13381) had a perineal tear of third degree and 0.2% (29/13381) of fourth degree. In 2000-2002, the total incidence was 6.6% (813/12380), 5.9% (731/12380) was a third degree perineal tear and 0.7% (82/12380) fourth degree, respectively. The sensitivity and specificity of the MBRN database to detect obstetric sphincter tears was 85.3 and 99.5% in 1990-1992, and 91.8 and 99.7% in 2000-2002, respectively. The positive and negative predictive values of a MBRN-registered diagnosis of obstetric sphincter tears in 1990-1992 were 91.4 and 99.1%, while the corresponding percentages in 2000-2002 were 95.4 and 99.4%, respectively. The sensitivity and specificity of the PAS database was correspondingly 52.1 and 99.0% in 1990-1992, and 84.6 and 98.5% in 2000-2002. The positive and negative predictive values of a PAS-diagnosis of obstetric sphincter tears were 75.8 and 97.1% in 1990-1992. In 2000-2002, they were 92.7 and 98.9%, respectively. Conclusion. The validity of a diagnosis of obstetric sphincter tears, based on the MBRN, is sufficiently high to justify future large-scale epidemiologic studies based on this database, while the validity of a PAS diagnosis is lower, but improves.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Introduction
Cesarean section is the single most important risk factor for postpartum infection. Where the rest of the world shows increasing trends, the cesarean section rates are low in Norway and ...risk factors for infection after cesarean section may differ in high and low cesarean section settings. The goal of this study was to examine independent risk factors for surgical site infection after cesarean delivery in a setting of low cesarean section rates.
Material and methods
We conducted a hospital‐based case‐control study at Haukeland University Hospital. We included women who presented to our hospital with surgical site infection after cesarean section during the years 2014–2016 (n = 75). Controls were selected at a ratio of 2:1 (n = 148). Cases and controls were compared with respect to maternal and pregnancy characteristics using uni‐ and multivariable logistic regression models. Main outcome measures were anticipated risk factors for surgical site infection.
Results
The occurrence of surgical site infection was 0.4% and 5.4% after elective and emergency cesarean section, respectively. Compared to women without surgical site infection, women with surgical site infection were almost thrice more obese before pregnancy (OR 2.8, 95% CI 1.2–7.0), four times more likely to have preexisting psychiatric conditions (OR 4.4, 95% CI 1.1–17.6), and five times more likely to receive blood transfusion (OR 5.1, 95% CI 1.4–18.8). Signs of infection during labor was a marginally significant risk factor for surgical site infection (OR 2.0, 95% CI 1.0–5.4).
Conclusions
Emergency cesarean section was a significant risk factor for surgical site infection. Pregestational obesity, preexisting psychiatric conditions, and blood transfusion during or following delivery, were independent risk factors for surgical site infection. Signs of infection during labor was a marginally significant risk factor. Women with either of these risk factors should be carefully monitored and evaluated for signs of infection in the postpartum period.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Earlier studies indicate that midwife-led birth settings are associated with modest benefits, including reduced medical interventions and increased maternal satisfaction. The generalizability of ...these studies to birth settings with low intervention rates, like those generally found in Norway, is not obvious. The aim of the present study was to compare intervention rates associated with labour in low-risk women who begin their labour in a midwife-led unit and a conventional care unit.
Eligible participants were low-risk primiparas who met the criteria for delivery in the midwife-led ward regardless of which cohort they were allocated to. The two wards are localised at the same floor. Women in both cohorts received the same standardized public antenatal care by general medical practitioners and midwifes who were not involved in the delivery. After admission of a woman to the midwife-led ward, the next woman who met the inclusion criteria, but preferred delivery at the conventional delivery ward, was allocated to the conventional delivery ward cohort. Among the 252 women in the midwife-led ward cohort, 74 (29%) women were transferred to the conventional delivery ward during labour.
Emergency caesarean and instrumental delivery rates in women who were admitted to the midwife-led and conventional birth wards were statistically non-different, but more women admitted to the conventional birth ward had episiotomy. More women in the conventional delivery ward received epidural analgesia, pudental nerve block and nitrous oxide, while more women in the midwife-led ward received opiates and non-pharmacological pain relief.
We did not find evidence that starting delivery in the midwife-led setting offers the advantage of lower operative delivery rates. However, epidural analgesia, pudental nerve block and episiotomies were less often while non-pharmacological pain relief was often used in the midwife-led ward.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Previous studies have established a history of shoulder dystocia as an important risk factor for shoulder dystocia, but studies on shoulder dystocia by severity are scarce. It is unknown if shoulder ...dystocia tends to be passed on between generations. We aimed to assess the recurrence risk of shoulder dystocia by severity in the same woman and between generations on both the maternal and paternal side. We also assessed the likelihood of a second delivery and planned cesarean section after shoulder dystocia.
This was a population-based cohort study, using data from the Medical Birth Registry of Norway. To study recurrence in the same mother, we identified 1 091 067 pairs of first and second, second and third, and third and fourth births in the same mother. To study intergenerational recurrence, we identified an individual both as a newborn and as a mother or father in 824 323 mother-offspring pairs and 614 663 father-offspring pairs. We used Bayesian log-binomial multilevel regression to calculate relative risks (RR) with 95% credible intervals.
In subsequent deliveries in the same woman the unadjusted RR of recurrence was 7.05 (95% credible interval 6.39-7.79) and 2.99 (2.71-3.31) after adjusting for possible confounders, including current birthweight. The RRs were higher with severe shoulder dystocia as exposure or outcome. With severe shoulder dystocia as both exposure and outcome, unadjusted and adjusted RR was 20.42 (14.25-29.26) and 6.29 (4.41-8.99), respectively. Women with severe and mild shoulder dystocia and those without had subsequent delivery rates of 71.1, 68.9 and 69.0%, respectively. However, the rates of planned cesarean section in subsequent deliveries for those without shoulder dystocia, mild and severe were 1.3, 5.2 and 16.0%, respectively. On the maternal side the unadjusted inter-generational RR of recurrence was 2.82 (2.25-3.54) and 1.41 (1.05-1.90) on the paternal side. Corresponding adjusted RRs were 1.90 (1.51-2.40) and 1.19 (0.88-1.61), respectively.
We found a strong recurrence risk of shoulder dystocia, especially severe, in subsequent deliveries in the same woman. The inter-generational recurrence risk was higher on the maternal than paternal side. Women with a history of shoulder dystocia had more often planned cesarean section.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Introduction
Isolated single umbilical artery (iSUA) refers to single umbilical artery cords with no other fetal malformations. The association of iSUA to adverse outcome of pregnancy has not been ...consistently reported, and whether iSUA carries increased risk of third stage of labor complications has not been studied. We aimed to investigate the risk of adverse perinatal outcome, third stage of labor complications, and associated placental and cord characteristics in pregnancies with iSUA. A further aim was to assess the risk of recurrence of iSUA and anomalous cord or placenta characteristics in Norway.
Material and methods
This was a population‐based study of all singleton pregnancies with gestational age >16 weeks at birth using data from the Medical Birth Registry of Norway from 1999 to 2014 (n = 918 933). Odds ratios (OR) with 95% confidence intervals were calculated for adverse perinatal outcome (preterm birth, perinatal and intrauterine death, low Apgar score, transferral to neonatal intensive care ward, placental and cord characteristics placental weight, cord length and knots, anomalous cord insertion, placental abruption and previa), and third stage of labor complications (postpartum hemorrhage and the need for manual placental removal or curettage) in pregnancies with iSUA, and recurrence of iSUA using generalized estimating equations and logistic regression.
Results
Pregnancies with iSUA carried increased risk of adverse perinatal outcome (OR 5.06, 95% confidence interval CI 4.26‐6.02) and perinatal and intrauterine death (OR 5.62, 95% CI 4.69‐6.73), and a 73% and 55% increased risk of preterm birth and small‐for‐gestational‐age neonate, respectively. The presence of iSUA also carried increased risk of a small placenta, placenta previa and abruption, anomalous cord insertion, long cord, cord knot and third stage of labor complications. Women with iSUA, long cord or anomalous cord insertion in one pregnancy carried increased risk of iSUA in the subsequent pregnancy.
Conclusions
The presence of ISUA was associated with a more than five times increased risk of intrauterine and perinatal death and with placental and cord complications. The high associated risk of adverse outcome justifies follow up with assessment of fetal wellbeing in the third trimester, intrapartum surveillance and preparedness for third stage of labor complications.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Obstetric fistula in 14,928 Ethiopian women Muleta, Mulu; Rasmussen, Svein; Kiserud, Torvid
Acta obstetricia et gynecologica Scandinavica,
July 2010, Volume:
89, Issue:
7
Journal Article
Peer reviewed
Abstract
Objectives. Obstetric fistulas are severe sequelae of prolonged obstructed labor, a widespread but incompletely documented problem of low-income countries. Here, we characterize women with ...obstetric fistula, test the hypothesis that primi- and multipara represent different profiles and that fetal size is an important factor in developing fistula. Design. Hospital registry statistics and questionnaire. Population. A total of 14,928 Ethiopian women with obstetric fistula in 1974-2006 and 434 admitted in 2007-8. Methods. Self-reported age, marital status, education, distance from home to health facility, parity, duration of labor, neonatal outcome and sex, lag time to treatment; measurement of weight, stature, extent of lesion and clinical assessment of continence before hospital discharge. Outcome measures. Duration of labor, extent of pelvic injury and neonatal survival, cure rate. Results. Primi- were more common than multiparous cases (56.8 vs. 43.2%). They were of similar age at marriage (17 years) and stature at hospital admission, but shorter than the population average (152.7 vs. 156.5 cm). Primipara had longer labor than multipara (50.5% > 3 days vs. 27%), larger uro-vaginal fistula, more stillbirths (95 vs. 88%), recto-vaginal fistula, vaginal scarring, persistent incontinence after repair and were more commonly divorced. Male fetuses were involved in 76.7% of obstructed deliveries but in only 44.6% of a previous uneventful delivery in multipara. Educational attainment positively influenced outcomes. Conclusions. Obstetric fistula is more commonly associated with primiparous than subsequent pregnancies. Primipara have a longer and more damaging labor. A causative role for cephalo-pelvic disproportion is supported by the observation that male fetuses are more commonly involved in obstructed labor.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background. Increasing cesarean section (CS) rates over the last 3 decades may, in part, be explained by improved obstetric procedures, but socio-economic factors also play a major role. Much ...attention has been given to professionals' attitudes to operative delivery, and several studies have been performed to clarify the issue. The present study explored CS rates among Norwegian doctors and midwives, compared to other professionals with an education of 17-18 years (doctors) and 15-16 years (midwives). Methods. Data on mode of delivery notified to the Medical Birth Registry of Norway for 1969-1998 (n=1,733,665) were linked with data on formal education from Statistics Norway. CS rates and crude and adjusted odds ratios (ORs) were calculated for the observation period. Results. Female doctors and midwives had higher CS rates; the crude ORs were 1.18 (95% CI: 1.12-1.28) for doctors, and 1.35 (95% CI: 1.21-1.49) for midwives. Adjusted for age and birth order, the ORs were 1.22 (95% CI: 1.12-1.33) for doctors and 1.14 (95% CI: 1.03-1.27) for midwives. Conclusion. From 1969 to 1998, Norwegian female doctors and midwives had higher CS rates than other professionals with an education of comparable duration.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
OBJECTIVE:To investigate risk factors for obstetric anal sphincter injuries in a large population-based data set, and to assess to what extent changes in these risk factors could account for trends ...in obstetric anal sphincter injuries.
METHODS:This is a population-based cohort study on data from the Medical Birth Registry of Norway between 1967 and 2004, including all vaginal singleton deliveries of vertex-presenting fetuses weighing 500 g or more. Women with their first birth before 1967 and births with previous obstetric anal sphincter injuries were excluded, leaving 1,673,442 births for study. The outcome variable was third- and fourth-degree obstetric anal sphincter injuries. The associations of obstetric anal sphincter injuries with possible risk factors were estimated by odds ratios (ORs) obtained by logistic regression.
RESULTS:The occurrence of obstetric anal sphincter injuries increased from 0.5% in 1967 to 4.1% in 2004. After adjusting for demographic and other risk factors, as well as possible confounders, the increase of obstetric anal sphincter injuries persisted, although reduced (unadjusted OR 7.1; 95% confidence interval CI 6.8–7.4; adjusted OR 5.6; 95% CI 5.3–5.9). Obstetric anal sphincter injuries were significantly associated with maternal age 30 years or older, vaginal birth order of one, previous cesarean delivery, instrumental delivery, episiotomy, type 1 diabetes, gestational diabetes, induction of labor by prostaglandin, size of maternity unit, birth weight 3,500 g or more, head circumference 35 cm or more, and African or Asian country of birth.
CONCLUSION:Risk of obstetric anal sphincter injuries considerably increased in Norway in 1967 to 2004. Changes in the risk factors studied could only partially explain this increase.
LEVEL OF EVIDENCE:II
PDF
