In pregnancies after a previous cesarean section (CS), a planned repeat CS delivery has been associated with excess risk of adverse outcome. However, also the alternative, a trial of labor after CS ...(TOLAC), has been associated with excess risks. A TOLAC failure, involving a non-planned CS, carries the highest risk of adverse outcome and a vaginal delivery the lowest. Thus, the decision regarding delivery mode is pivotal in clinical handling of these pregnancies. However, even with a high TOLAC rate, as seen in Norway, repeat CSs are regularly performed for no apparent medical reason. The objective of the present study was to assess to which extent demographic, socioeconomic, and health system factors are determinants of TOLAC and TOLAC failure in low risk pregnancies, and whether any effects observed changed with time.
The study group comprised 24 645 second deliveries (1989-2014) after a first delivery CS. Thus, none of the women had prior vaginal deliveries or more than one CS. Included pregnancies were low risk, cephalic, single, and had gestational age ≥ 37 weeks. Data were obtained from the Medical Birth Registry of Norway (MBRN). The exposure variables were (second delivery) maternal age, length of maternal education, maternal country of origin, size of the delivery unit, health region (South-East, West, Mid, North), and maternal county of residence. The outcomes were TOLAC and TOLAC failure, as rates (%), relative risk (RR) and relative risk adjusted (ARR). Changes in determinant effects over time were assessed by comparing rates in two periods, 1989-2002 vs 2003-2014, and including these periods in an interaction model.
The TOLAC rate was 74.9%, with a TOLAC failure rate of 16.2%, resulting in a vaginal birth rate of 62.8%. Low TOLAC rates were observed at high maternal age and in women from East Asia or Latin America. High TOLAC failure rates were observed at high maternal age, in women with less than 11 years of education, and in women of non-western origin. The effects of health system factors, i.e. delivery unit size and administrative region were considerable, on both TOLAC and TOLAC failure. The effects of several determinants changed significantly (P < 0.05) from 1989-2002 to 2003-2014: The association between non-TOLAC and maternal age > 39 years became weaker, the association between short education and TOLAC failure became stronger, and the association between TOLAC failure and small size of delivery unit became stronger.
Low maternal age, high education, and western country of origin were associated with high TOLAC rates, and low TOLAC failure rates. Maternity unit characteristics (size and region) contributed with effects on the same level as individual determinants studied. Temporal changes were observed in determinant effects.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introduction
Anomalous cord insertion is associated with increased risk of adverse maternal and perinatal outcome. Our aim was to study whether anomalous cord insertion is associated with prelabor ...rupture of membranes (PROM), preterm PROM (pPROM), long or short umbilical cord, and time trend of spontaneous preterm birth (SPTB) and anomalous cord insertion.
Material and methods
A population‐based register study using data from the Medical Birth Register of Norway including all singleton births (gestational age >16 weeks and <45 weeks) during 1999–2013 (n = 860 465) to calculate odds ratios (ORs) for PROM, pPROM, SPTB, and cord length (>95th or <5th centile) according to the cord insertion site by logistic regression with adjustment for possible confounders. We also assessed time trends of SPTB and anomalous cord insertion.
Results
Velamentous insertion of the cord was associated with an increased risk of PROM (OR 1.6, 95% CI 1.5–1.7), pPROM (OR 2.7, 95% CI 2.4–3.0), SPTB (OR 2.0, 95% CI 1.9–2.2), and a short cord (OR 1.7, 95% CI 1.5–1.8). Marginal insertion was to a lesser extent associated with these complications. Occurrences of SPTB and anomalous insertion declined. The decline in SPTB persisted after including an interaction term between anomalous insertion and time.
Conclusions
Velamentous and, to a lesser extent, marginal cord insertions were associated with increased risk of PROM, pPROM, SPTB, and short cord. This suggests a common pathogenesis behind altered function of the membranes, cord, and placenta. The decline in SPTB could not be explained by the reduction in the occurrence of anomalous cord insertion.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Objectives: Our goal was to determine the degree of shunting through the ductus venosus in the human fetus and its possible association with fetal growth. Study Design: Blood flow in the umbilical ...vein and the fetal ductus venosus was measured in 197 low-risk pregnancies in a cross-sectional ultrasonographic study at a gestational age of 18 to 41 weeks. The degree of shunting was compared to birth weight and ponderal index. Results: The average fraction shunted through the ductus venosus was 28% to 32% at 18 to 20 weeks, decreased to 22% at 25 weeks, and reached 18% at 31 weeks (with wide ranges expressed in the 10th and 90th percentiles). Fetuses <10th percentile for birth weight had significantly more shunting (1.4%) than those >90th percentile (95% confidence interval, 0.1%-2.7%; P = .04). Conclusions: In the human fetus a higher proportion of umbilical blood is directed to the liver and less is shunted through the ductus venosus, in comparison with what has previously been shown in animal experiments. (Am J Obstet Gynecol 2000;182:147-53.)
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Objective Experimental studies show that fetal liver venous perfusion is a determinant for growth in utero. Here we explore the relationship between fetal venous blood flow to the liver and ...macrosomia. Study Design From diameter and blood flow velocity measurements, we derived liver venous blood flow in a longitudinal ultrasound study of 25 macrosomic fetuses of nondiabetic mothers during the second half of pregnancy. Results Compared with appropriately growing fetuses, macrosomic fetuses directed more umbilical blood to the liver tissue, with correspondingly less contribution from the portal circulation when normalized for fetal weight. Whereas total venous liver blood flow showed no late gestation rise in the reference population, it continued to increase in macrosomic fetuses and was accompanied by greater fetal weight. Conclusion The direct relationship between venous liver blood flow and macrosomia in the fetus supports the concept that intrauterine growth is linked to the amount and distributional pattern of venous liver perfusion.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Introduction
The human yolk sac provides the embryo with stem cells, nutrients, and gas exchange. We hypothesized that more maternal resources, reflected in body size and body composition, would ...condition a a larger yolk sac, ensuring resources for the growing embryo. Thus, we aimed to determine the relation between maternal size in early pregnancy and yolk sac size.
Material and methods
This subsidiary study was embedded in the multinational World Health Organization fetal growth project that included healthy women with a body mass index of 18‐30, reliable information of their regular last menstrual period and singleton pregnancies. Yolk sac diameter, crown‐rump length, and maternal height, weight, body mass index, and body composition were assessed before 13 weeks of gestation, and the fetal biometry was repeated during the pregnancy.
Results
Of 140 participants, 122 with a successful yolk sac measurement were entered in the present analysis. Maternal weight was negatively associated with the yolk sac diameter (P = 0.007) and so was maternal height (P = 0.011), fat mass (P = 0.037), and lean body mass (P = 0.018), but not body mass index (P = 0.121). Significant effects were predominantly due to the female embryos and could be traced at 24 weeks of gestation. That is, a small yolk sac : crown‐rump length ratio in early pregnancy was associated with a high fetal abdominal circumference (P < 0.001) and estimated fetal weight (P = 0.001).
Conclusions
The human yolk sac is involved in the regulation of embryonic growth, but contrary to our hypothesis, the yolk sac has a compensatory capacity, being larger when the mothers are smaller; and the effect can be traced on fetal size at 24 weeks of gestation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The modern phenomenon of delayed parenthood applies not only to women but also to men, but less is known about what characterises men who are expecting their first child at an advanced age. This ...study investigates the sociodemographic characteristics, health behaviour, health problems, social relationships and timing of pregnancy in older first-time fathers.
A cross-sectional study was conducted of 14 832 men who were expecting their first child, based on data from the Norwegian Mother and Child Cohort Study (MoBa) carried out by the Norwegian Institute of Public Health. Data were collected in 2005-2008 by means of a questionnaire in gestational week 17-18 of their partner's pregnancy, and from the Norwegian Medical Birth Register. The distribution of background variables was investigated across the age span of 25 years and above. Men of advanced age (35-39 years) and very advanced age (40 years or more) were compared with men aged 25-34 years by means of bivariate and multivariate logistic regression analyses.
The following factors were found to be associated with having the first child at an advanced or very advanced age: being unmarried or non-cohabitant, negative health behaviour (overweight, obesity, smoking, frequent alcohol intake), physical and mental health problems (lower back pain, cardiovascular diseases, high blood pressure, sleeping problems, previous depressive symptoms), few social contacts and dissatisfaction with partner relationship. There were mixed associations for socioeconomic status: several proxy measures of high socioeconomic status (e.g. income >65,000 €, self-employment) were associated with having the first child at an advanced or very advanced age, as were several other proxy measures of low socioeconomic status (e.g. unemployment, low level of education, immigrant background).The odds of the child being conceived after in vitro fertilisation were threefold in men aged 34-39 and fourfold from 40 years and above.
Men who expect their first baby at an advanced or very advanced age constitute a socioeconomically heterogeneous group with more health problems and more risky health behaviour than younger men. Since older men often have their first child with a woman of advanced age, in whom similar characteristics have been reported, their combined risk of adverse perinatal outcomes needs further attention by clinicians and researchers.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The authors investigated a possible association of supplemental folic acid and multivitamin use with placental abruption by using data on 280,127 singleton deliveries recorded in 1999–2004 in the ...population-based Medical Birth Registry of Norway. Odds ratios, adjusted for maternal age, marital status, parity, smoking, pregestational diabetes, and chronic hypertension, were estimated with generalized estimating equations for logistic regression models. Use of folic acid and/or multivitamin supplements before or any time during pregnancy was reported for 36.4% of the abruptions (0.38% of deliveries) and 44.4% of the nonabruptions. Compared with no use, any supplement use was associated with a 26% risk reduction of placental abruption (adjusted odds ratio = 0.74, 95% confidence interval: 0.65, 0.84). Women who had taken folic acid alone had an adjusted odds ratio of 0.81 (95% confidence interval: 0.68, 0.98) for abruption, whereas multivitamin users had an adjusted odds ratio of 0.72 (95% confidence interval: 0.57, 0.91), relative to supplement nonusers. The strongest risk reduction was found for those who had taken both folic acid and multivitamin supplements (adjusted odds ratio = 0.68, 95% confidence interval: 0.56, 0.83). These data suggest that folic acid and other vitamin supplementation during pregnancy may be associated with reduced risk of placental abruption.
Abstract Objective To examine the occurrence of arthrogryposis multiplex congenita (AMC) in Europe and to identify possible risk factors. Study design Retrospective population-based epidemiological ...study using EUROCAT congenital anomaly registries. The study population included all cases of AMC (based on WHO ICD-9 or ICD-10 codes) that were livebirths (LB), fetal deaths (FD) from 20 weeks gestation and underwent termination of pregnancy for fetal anomaly (TOPFA), 1980–2006. Results Among 8.9 million births covered by 24 EUROCAT congenital anomaly registries, 757 AMC cases were reported. This gives a prevalence of 8.5 per 100,000. Five hundred and four (67%) AMC cases were LB, 199 (26%) cases were TOPFA, and FD occurred in 54 (7%) cases. First week survival status was known for 381 of the 504 LB (76%), of whom 87 (23%) died within the first week of life. Perinatal mortality associated with AMC was 32%. Two hundred and eighty-two (37%) cases had isolated AMC, 90 (12%) had additional syndrome or chromosomal anomalies and 385 (51%) had other major malformations. The same or similar anomaly was reported in 13% of siblings and in 12% of the mother's own family background. Information on prenatal testing was available for 521 cases of which 360 tested positive for a congenital anomaly, representing a sensitivity of 69%. Information on maternal illness before and during pregnancy and medication use in the first trimester was available for approximately a third of the mothers, of whom the vast majority reported no maternal illness or medication use. Conclusion AMC is a rare occurrence, with a reported prevalence of 1:12,000. In this study, while information on potential risk factors such as maternal disease or maternal use of drugs was limited, they did not appear to be associated with the occurrence of AMC. AMC was lethal in a third of cases, either in utero or during the first week of life, although this may not be solely attributed to AMC as most cases had additional malformations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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