Language impairment in children aged 5 and 8 years after antiepileptic drug exposure in utero - the Norwegian Mother and Child Cohort Study.

BACKGROUND AND PURPOSE: The purpose was to examine the consequences of antiepileptic drug (AED) exposure during pregnancy on language abilities in children aged 5 and 8 years of mothers with epilepsy. METHODS: The study population included children of mothers with and without epilepsy enrolled in the Norwegian Mother and Child Cohort Study 1999-2008. Mothers prospectively provided information on epilepsy diagnosis, AED use during pregnancy and the child's language abilities at age 5 and 8 years, in questionnaires with validated language screening tools. AED concentrations in gestation week 17-19 and in the umbilical cord were measured. RESULTS: The study population included 346 AED-exposed and 388 AED-unexposed children of mothers with epilepsy, and 113 674 children of mothers without epilepsy. Mothers of 117 and 121 AED-exposed children responded to the questionnaires at age 5 and 8 years, respectively. For AED-exposed children, the adjusted odds ratio for language impairment was 1.6 [confidence interval (CI) 1.1-2.5, P = 0.03] at age 5 years and 2.0 (CI 1.4-3.0, P < 0.001) at age 8 years, compared to children of mothers without epilepsy. Children exposed to carbamazepine monotherapy had a significantly increased risk of language impairment compared to control children at age 8 years (adjusted odds ratio 3.8, CI 1.6-9.0, P = 0.002). Higher maternal valproate concentrations correlated with language impairment at age 5 years. Periconceptional folic acid supplement use protected against AED-associated language impairment. CONCLUSION: Foetal AED exposure in utero is associated with an increased risk of language impairment in children aged 5 and 8 years of mothers with epilepsy. Periconceptional folic acid use had a protective effect on AED-associated language impairment.

Uterine rupture: trends over 40 years.

OBJECTIVE: To follow trends of uterine rupture over a period of 40 years in Norway. DESIGN: Population-based study using data from the Medical Birth Registry, the Patient Administration System, and medical records. SETTING: Norway. SAMPLE: Women giving birth in 21 maternity units in Norway during the period 1967-2008 (n = 1 441 712 maternities). METHODS: The incidence and outcomes of uterine rupture were compared across four decades: 1967-1977; 1978-1988; 1989-1999; and 2000-2008. Multivariable logistic regression was used to determine the odds ratio (OR) for uterine rupture in each decade compared with the second decade. MAIN OUTCOME MEASURE: Trends in uterine rupture. RESULTS: We identified 359 uterine ruptures. The incidence rates per 10 000 maternities in the first, second, third, and fourth decade were 1.2, 0.9, 1.7, and 6.1, respectively. The ORs for complete and partial ruptures in the fourth versus the second decade were 6.4 (95% confidence interval, 95% CI 3.8-10.8) and 7.2 (95% CI 4.2-12.3), respectively. Significant contributing factors to this increase were the higher rates of labour augmentation with oxytocin, scarred uteri from a previous caesarean section, and labour induction with prostaglandins or prostaglandins combined with oxytocin. After adjusting for risk factors, the ORs for complete and partial ruptures were 2.2 (95% CI 1.3-3.8) and 2.8 (95% CI 1.6-4.8), respectively. Severe postpartum haemorrhage, hysterectomy, intrapartum death and infant death after complete uterine ruptures decreased significantly over time. CONCLUSIONS: A sharply increasing trend of uterine rupture was found. Obstetric interventions contributed to this increase, but could not explain it entirely. TWEETABLE ABSTRACT: A sharply increasing trend of uterine ruptures has been found in Norway in recent years.

Obstetric outcome in women with epilepsy: a hospital-based, retrospective study.

OBJECTIVE: To report the complications during pregnancy and delivery in women with epilepsy, compared with a control group without epilepsy, with special focus on potential risk factors, such as epilepsy severity and dosage of antiepileptic drugs. DESIGN: Hospital-based retrospective study. SETTING: Data from pregnancy notification forms and hospital case records. POPULATION: Women with a past or present history of epilepsy (n = 205) delivered in Bergen, Norway, in the period 1999-2006, and a matched control group of women (n = 205) without epilepsy. METHODS: Data were compared and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by multiple logistic regression models. MAIN OUTCOME MEASURES: Pre-eclampsia (mild and severe), gestational hypertension, vaginal bleeding (early and late), caesarean section, vaginal operative delivery, postpartum haemorrhage and major malformations. RESULTS: Women with epilepsy using antiepileptic drugs had an increased risk of severe pre-eclampsia (OR, 5.0; 95% CI, 1.3-19.9), bleeding in early pregnancy (OR, 6.4; 95% CI, 2.7-15.2), induction (OR, 2.3; 95% CI, 1.2-4.3) and caesarean section (OR, 2.5; 95% CI, 1.4-4.7) adjusted for maternal age, parity, education, smoking, medical conditions and body mass index ≥30 kg/m(2) . There was also an increased risk of malformations in the offspring (OR, 7.1; 95% CI, 1.4-36.6). Women without antiepileptic drug use had increased risks of forceps delivery and preterm birth. Active epilepsy (seizures during the last 5 years) versus nonactive epilepsy did not discriminate for any of these complications; 84.5% of women with epilepsy and antiepileptic drug use were using folate. CONCLUSION: Women with epilepsy using antiepileptic drugs had an increased risk of pregnancy and delivery complications, whereas women not using antiepileptic drugs had few complications. Seizures, high doses of antiepileptic drugs, obesity and lack of folate could not explain these increased risks.

Delivery outcome of women with epilepsy: a population-based cohort study.

OBJECTIVE: To investigate whether women with epilepsy have increased risks of complications during labour, and to explore the impact of antiepileptic drug use. DESIGN: Population-based cohort study. SETTING: Data from the Medical Birth Registry of Norway 1999-2005. POPULATION: All births (n=372,128) delivered in Norway, ensured through linkage with the National Population Registry run by Statistics Norway. All singleton births and the first child in multiple pregnancies were included, leaving 365,107 pregnancies for analysis. METHODS: Data from the Medical Birth Registry of Norway 1999-2005 were analysed. MAIN OUTCOME MEASURES: Induction, caesarean section, use of forceps and vacuum, abnormal presentation, placental abruption, mechanical disproportion, postpartum haemorrhage, atony and Apgar score <7 after 5 minutes. RESULTS: We compared 2805 pregnancies in women with a current or past history of epilepsy (0.8%) and 362,302 pregnancies in women without a history of epilepsy. Antiepileptic drugs were used in 33.6% (n=942) of pregnant women with epilepsy. Women with epilepsy had an increased risk of induction [odds ratio (OR), 1.3; 95% confidence interval (CI), 1.1-1.4], caesarean section (OR, 1.4; 95% CI, 1.3-1.6) and postpartum haemorrhage (OR, 1.2; 95% CI, 1.1-1.4) compared with women without epilepsy. These rates were even higher for women with epilepsy and antiepileptic drug use, with ORs (95% CIs) of 1.6 (1.4-1.9), 1.6 (1.4-1.9) and 1.5 (1.3-1.9), respectively. In addition, the risk of an Apgar score <7 was higher (OR, 1.6; 95% CI, 1.1-2.4). For women with epilepsy without antiepileptic drug use, only a slightly increased risk of caesarean delivery was observed and no increased risk for any other complications studied. CONCLUSIONS: Pregnant women with epilepsy have a low complication rate; however, they have a slightly increased risk of induction, caesarean section and postpartum haemorrhage. It is not possible to ascertain on the basis of this study whether this is a result of more severe epilepsy or antiepileptic drug use.

Complications during pregnancy in women with epilepsy: population-based cohort study.

OBJECTIVE: To investigate whether women with epilepsy have an increased risk of complications during pregnancy and to explore the impact of antiepileptic drug (AED) use. DESIGN: Population-based cohort study. SETTING: Data from Medical Birth Registry of Norway based on all births in Norway 1999-2005. POPULATION: All births (n=372,128) delivered in Norway, ensured through linkage with the National Population Registry run by Statistics Norway. All singleton births and the first child in multiple pregnancies were included, leaving 365,107 pregnancies for analyses. MAIN OUTCOME MEASURES: Pre-eclampsia (mild and severe), gestational hypertension, eclampsia, vaginal bleeding (early and late) and preterm birth. RESULTS: We compared 2805 pregnancies in women with a current or past history of epilepsy (0.8%) and 362 302 pregnancies in women without a history of epilepsy. Women with epilepsy had an increased risk of mild pre-eclampsia, [odds ratio 1.3: 95% confidence interval (1.1-1.5)] and delivery before week 34 [1.2: (1.0-1.5)]. Antiepileptic drugs were used in 33.6% (n=942) of the pregnant women with epilepsy. Compared to women without epilepsy, women with epilepsy and AED use had an increased risk of mild pre-eclampsia [1.8: (1.3-2.4)], gestational hypertension [1.5: (1.0-2.2)], vaginal bleeding late in pregnancy [1.9: (1.1-3.2)], and delivery before 34 weeks of gestation [1.5: (1.1-2.0)]. No significant increase in the risk of these complications was observed in women with epilepsy not using AED. These results remained unchanged after exclusion of multiple pregnancies. CONCLUSION: Women with epilepsy have a low complication rate, but special attention should be paid to those using AED during pregnancy.

Antenatal ultrasound and postnatal autopsy findings in terminations after 12 weeks' gestation due to fetal abnormality: population-based study in Western Norway, 1988-2002.

BACKGROUND: Ultrasound screening has been part of antenatal care for several decades, and warrants high expertise to meet the criteria for a worthwhile screening program. In particular, the rate of false positives should be low. PURPOSE: To examine time trends of pregnancy terminations for fetal abnormality after 12 weeks' gestation, and to assess the agreement between antenatal ultrasound and post-termination autopsy findings for the main pathologies leading to termination. MATERIAL AND METHODS: During the period 1988 to 2002, 198 pregnancies were terminated for fetal abnormality after 12 weeks' gestation. We reviewed the case notes for those 151 who were autopsied (male/female/undetermined ;= ;91/56/4). Annual rates of live births and stillbirths were retrieved from the Medical Birth Registry of Norway. RESULTS: Antenatal ultrasound provided a correct diagnosis of the major abnormality in 149/151 cases (99%), based on post-termination autopsy findings. The annual rate of terminations after 12 weeks' gestation varied between 0.6 and 3.4 (mean 1.8) per 1000 live births, with a trend toward higher rates over the study period (P=0.001, chi-square test for linear-by-linear association). CONCLUSION: The specificity of antenatal ultrasound for major abnormalities was high, as compared to postnatal autopsy findings. The mean annual rates of termination after 12 weeks' gestation tended to increase over the 14-year study period.

Sociodemographic characteristics and perinatal mortality among singletons in North East Tanzania: a registry-based study.

OBJECTIVES: Sub-Saharan Africa has the highest known perinatal mortality rates in the World, but few studies have assessed the importance of parental sociodemographic characteristics on perinatal mortality in this region. The aim of this study was to estimate how sociodemographic patterns affect perinatal mortality in Northern Tanzania. DESIGN AND SETTINGS: A registry-based study using births from 1999 to 2006 at a hospital in North Eastern Tanzania. PARTICIPANTS AND METHODS: 14 394 singleton births with birthweight 500 g or higher and a known perinatal survival status. Births of women with residence outside the local district who were referred to the hospital for delivery for medical reasons were excluded. RESULTS: Perinatal mortality was 41.1 per 1000 births. Factors independently associated with higher perinatal mortality were: higher paternal age (> 45) compared to age 26-35 (adjusted relative risk (ARR) 2.0; 95% CI 1.4 to 2.8), low paternal education (only primary) compared to secondary or higher (ARR 1.3; 95% CI 1.1 to 1.7), paternal ethnicity other than Chagga or Pare (ARR 1.4; 95% CI 1.1 to 1.7), paternal farming occupation (ARR 1.5; 95% CI 1.1 to 2.2), maternal service occupation (ARR 1.7; 95% CI 1.2 to 2.6), maternal height 150 cm or lower (ARR 1.4; 95% CI 1.0 to 1.8) and residence in the rural or semi-urban area (ARR 1.4; 95% CI 1.1 to 1.7). CONCLUSIONS: There are strong sociodemographic gradients in perinatal mortality in Africa. Paternal social characteristics appear to have stronger influence on perinatal mortality than maternal characteristics. This may reflect social and cultural conditions that need to be considered by policymakers in developing countries.

Maternal HIV status and pregnancy outcomes in northeastern Tanzania: a registry-based study.

OBJECTIVES: The proportion of women delivering with known HIV status in sub-Saharan Africa is not well described. Risk of HIV transmission to newborns is a major concern, but there may also be increased risks for other adverse pregnancy outcomes. DESIGN: Hospital registry. SETTING: North East Tanzania (1999-2006). POPULATION: Singletons (n = 14,444). METHODS: Births were grouped by maternal HIV status and socio-demographic factors predicting HIV status, and associations between status and pregnancy outcomes were studied. MAIN OUTCOME MEASURES: Maternal HIV status, perinatal mortality, prematurity, small for gestational age (SGA), birthweight and low Apgar score. RESULTS: The proportion of mothers with known HIV status increased from 7% before 2001 to 78% after 2004. Single motherhood, rural residence, low maternal education, maternal and paternal farming and higher paternal age were associated with unknown HIV status. About 7.4% (95% CI 6.7-8.1%) of women were HIV infected, with increased likelihood of infection with higher gravidity, single motherhood, rural residence, maternal business or farming occupations and paternal tribe. Compared with HIV-uninfected women, the untreated HIV-infected women had a higher risk of SGA births (adjusted risk ratio [ARR] 1.6; 95% CI 1.1-2.4), preterm birth (ARR 1.8; 95% CI 1.1-2.7) and perinatal death (ARR 1.9; 95% CI 0.95-3.8). Women with unknown HIV status had moderately increased risks. Treated HIV-infected women had a risk similar to that of the HIV-uninfected women for all outcomes, except for low Apgar score. CONCLUSION: HIV testing and infection were associated with socio-demographic factors. Untreated HIV-infected women had higher risks of adverse pregnancy outcomes, and risks were also increased for women with unknown HIV status. There is still a need to increase availability of HIV testing, education and adequate therapy for pregnant women.

Is smoking an extra hazard in pregnant MS women? Findings from a population-based registry in Norway.

Multiple sclerosis (MS) in women leads to increased risk of operative delivery and reduced birth weight, which are presumably related to the neurological dysfunction in this patient group. Lifestyle factors may also contribute, and we therefore investigated smoking habits and relevant social factors in pregnant MS women. In total, 372,128 births were registered in the compulsory Medical Birth Registry of Norway from December 1, 1998 to October 6, 2005, and of them 250 by MS mothers. The MS births were compared with all the non-MS births. Smoking during pregnancy was not increased in the MS group compared with the non-MS references. From 1998 to 2005 the MS group had a larger reduction in smoking rate during pregnancy than the reference group. The differences in pregnancy and birth outcome between smokers and non-smokers were similar in the MS and the reference group. Those in the smoking MS group had no increase in birth complications, operative interventions or negative birth outcome compared with those in the smoking reference group. Smoking during pregnancy did not explain the birth weight reduction found for newborns of MS mothers.

Myasthenia gravis in pregnancy and birth: identifying risk factors, optimising care.

Women with myasthenia gravis (MG) have increased risk of pregnancy complications and an adverse pregnancy outcome. This study examined risk factors for such complications in order to improve the care for pregnant MG women. Through the Medical Birth Registry of Norway, 73 MG mothers with 135 births were identified. Their obstetrical and clinical records were examined. Data on pregnancy, delivery and the newborn were combined with information on mother's disease. The risk for neonatal MG was halved if the mother was thymectomized (P = 0.03). Children with neonatal MG were more likely to display signs of foetal distress during delivery (P = 0.05). Only in one-third of the pregnancies did the patient see a neurologist during pregnancy. These patients used MG medication more often during pregnancy (P = 0.001), and were more likely to be thymectomized (P = 0.007). They also had a higher rate of elective sections (P = 0.009). Thymectomy may have a protective effect against neonatal MG. Neonatal MG can cause foetal distress during delivery. Most MG women benefit from being examined by a neurologist during pregnancy, to minimize risks and select the best delivery mode in collaboration with obstetricians.

Outcomes in adulthood for children with foetal growth retardation. A linkage study from the Nord-Trøndelag Health Study (HUNT) and the Medical Birth Registry of Norway.

OBJECTIVE: The aims were to examine the long-term functional outcome and risk of mood disorders in adulthood in individuals with foetal growth retardation. METHOD: In a prospective cohort study of 7806 individuals aged 20-30 years, using linked data from the Health Survey of Nord-Trøndelag (HUNT-2) and the Medical Birth Registry of Norway, we studied the long-term effects of being born with a birth weight below the 10th percentile for gestational age (SGA). RESULTS: SGA individuals had lower educational level (OR: 1.33), lower socioeconomic functioning level (OR: 1.77) and more frequent reported mood disorder in adulthood (OR: 1.26). Analyses of a substratum of infants born at term showed almost identical results. CONCLUSION: Foetal growth retardation measured as SGA shows a moderate risk for lower education and socioeconomic level and for anxiety and/or depression in young adulthood. Issues concerning interventions for children at risk should be considered.

Artrogryposis multiplex congenita -- a rare fetal condition caused by maternal myasthenia gravis.

OBJECTIVES: To look at the occurrence of arthrogryposis multiplex congenita in newborn of mothers with myasthenia gravis (MG) and factors connected to this. MATERIAL AND METHODS: We retrospectively studied 176 births by 79 MG mothers, recorded in the Medical Birth Registry of Norway (MBRN). Four (2.2%) newborns (including one pair of twins) born with severe skeletal anomalies were identified. RESULTS: All four children died. Three had findings consistent with arthrogryposis multiplexa congenita (AMC), one had a fetal akinesia deformation sequence (FADS). The mother of the child with FADS had previously given birth to a child with neonatal MG. She was now in complete MG remission. The mother of the twins with AMC later gave birth to a child with neonatal MG. CONCLUSION: Siblings of an affected child -- either with neonatal MG or AMC -- have an increased risk to develop either neonatal MG or AMC. As this appears to be independent of the MG mother's clinical state, it is important to discuss previous pregnancy outcomes with all female MG patients.

Does myasthenia gravis provide protection against cancer?

OBJECTIVES: Reports have been made of an altered rate of extrathymic malignancies in patients with myasthenia gravis (MG). This study compared the rate of such malignancies in a group of MG patients with an optimal control group. MATERIALS AND METHODS: From the Norwegian Cause of Death Registry, we identified 249 dead MG patients (1951-2001) and a control group of 1,245 individuals (five per patient) dead in the same period, matched for sex and year of birth. RESULTS: Patients with MG had a lower occurrence of malignant disease as underlying or contributing cause of death than the controls (8.8% vs 27.2%, P < 0.001). The main difference was found for colorectal cancer, breast cancer and cancer in the upper digestive tract (esophagus and stomach). CONCLUSIONS: We report a significantly lower rate of extrathymic malignancies in patients with MG than in controls, and we hypothesize that MG treatment or the immunological mechanisms involved in MG may protect patients with MG from developing an extrathymic malignancy.

Planned vaginal births in women with multiple sclerosis: delivery and birth outcome.

OBJECTIVE: The objective of this study was to investigate the effect of maternal multiple sclerosis (MS) on delivery and birth outcome in births without planned caesarean section. METHODS: Data were collected from the compulsory Medical Birth Registry of Norway from 1988 to 2002. Intended vaginal births in this time period were 449 births given by MS mothers and 851,060 control births. RESULTS: The MS mothers had a higher rate of induction of labour, and there was a strong trend for slower progression of second stage of labour and increased use of forceps. The MS group had lower birth weight and length of the neonates. The frequency of birth defects and the neonatal mortality were not increased in the MS group. CONCLUSIONS: Maternal MS affects the birth process and the neonate prenatally, even when the births with planned caesarean section are excluded. MS-related neuronal dysfunction linked to the uterus, is postulated as the most likely mechanism.

Risk factors for testicular cancer--differences between pure non-seminoma and mixed seminoma/non-seminoma?

The origin of testicular germ cell cancer (TGCC) is believed to be carcinoma in situ cells developed in utero. Clinically, TGCCs are divided into two major histological groups, seminomas and non-seminomas, where the latter group includes non-seminomatous TGCCs with seminomatous components (mixed S/NS TGCC). Recent studies, however, have suggested that non-seminomas and mixed S/NS TGCCs could have certain differences in aetiology, and in this study the TGCCs were divided into three, rather than the conventional two histological groups. A large case-control study was undertaken on data on all live-born boys registered in the Medical Birth Registry of Norway during the period 1967-1998 (n=961 396). Among these were 1087 TGCC cases registered in the Cancer Registry of Norway until February 2004. We found several risk factors for TGCC, including low parity, low gestational age, epilepsy and retained placenta. Several of the variables studied seemed to be risk factors for specific histological groups, e.g. parity 0 vs. 2 and low gestational age being associated with increased risk of non-seminomas, but not of mixed S/NS TGCC, and low maternal age being associated with increased risk of mixed S/NS TGCC, but not of non-seminomatous TGCC. Therefore, our results might suggest that non-seminomas and mixed S/NS TGCCs have partially different risk factors, whose associations may be obscured by combining these two histological groups. The histological groups were not significantly different, however. Most of our findings on risk factors for TGCC are in agreement with at least some previous studies. An unexplainable exception is low birth weight being associated with reduced risk of TGCC in our study.

Causes of death among patients with myasthenia gravis in Norway between 1951 and 2001.

OBJECTIVE: This study investigated the causes of death among patients with myasthenia gravis (MG), with emphasis on respiratory tract and cardiac disease. METHODS: The Norwegian Cause of Death Register contains information on all deaths among Norwegian citizens. In total, 249 deceased patients with MG were identified (1951-2001). These were compared with 1245 controls deceased in the same period and matched for sex and year of birth. RESULTS: The death certificates of patients with MG had a significantly higher occurrence of respiratory tract disease as cause of death than controls (28.1% v 20.9%, p = 0.012). The difference was most pronounced for male patients, for patients dying between 30 and 69 years of age, and for deaths occurring before 1996. For cardiac disease there was a significantly lower occurrence among patients with MG than among controls at 50-69 years of age, for both men (19.4% v 52.0%, p = 0.001) and women (14.6% v 29.6%, p = 0.036). Age and year of death were important determinants for the causes of death, but could not account for the differences between the patients with MG and controls. CONCLUSIONS: This study shows that patients with MG dying between 1951 and 1995 had a higher occurrence of respiratory tract disease listed as cause of death than had a matched control group. The lack of difference after 1995 probably reflects improved treatment of MG and its complications. The reduced occurrence of cardiac disease among patients with MG is probably explained by competing factors (respiratory tract disease) causing death.

Pregnancy, delivery, and birth outcome in women with multiple sclerosis.

Using data from the compulsory Medical Birth Registry of Norway, the authors investigated the effect of maternal multiple sclerosis (MS) on pregnancy, delivery, and birth outcome in 649 births by MS mothers and 2.1 million control births. The mothers with MS had a higher proportion of neonates small for gestational age and also more frequent induction and operative interventions during delivery.

Neonatal outcomes in offspring of women with anxiety and depression during pregnancy. A linkage study from The Nord-Trøndelag Health Study (HUNT) and Medical Birth Registry of Norway.

BACKGROUND: The presence of mental disorder during pregnancy could affect the offspring. AIMS: To examine the effects of anxiety disorder and depression in pregnant women on neonatal outcomes, and to compare neonatal outcomes between offspring of attendees and non-attendees in a general population-based health survey. METHOD: Pregnant women (n = 680) were identified from the population-based health study of Nord-TrØndelag County (HUNT-2) by linkage with the Medical Birth Registry of Norway. The women rated themselves on the Hospital Anxiety and Depression Rating Scale (HADS). Outcome variables were gestational length, birth weight, and Apgar scores. RESULTS: HADS-defined anxiety disorder during pregnancy was associated with lower Apgar score at one minute (score < 8; odds ratio = 2.27; p = .03) and five minutes (score < 8; odds ratio = 4.49; p = .016). No confounders were identified. Anxiety disorder and depression during pregnancy was not associated with low birth weight or preterm delivery. Offspring of non-attendees had a lower birth weight (77 g; t = 3.27; p = 0.001) and a shorter gestational length (1.8 days; t = 2.76; p = 0.006) than that of offspring of attendees, a difference that may be explained by a higher load of psychosocial risk factors among the non-attendees. CONCLUSION: In our study that may be biased towards the healthier among pregnant women, anxiety disorder or depression during pregnancy were not strong risk factors for adverse neonatal outcomes although low Apgar score in offspring of women with anxiety disorder may indicate poor neonatal adaptation.

Asymptomatic myasthenia gravis influences pregnancy and birth.

Women with myasthenia gravis (MG) have an increased risk of complications and adverse pregnancy outcome. This study has examined if this is true also for asymptomatic MG. Using data from the Medical Birth Registry of Norway, births of women prior to receiving an MG diagnosis or in complete clinical MG remission were compared with all non-MG births in Norway in the same period (1967-2000). Forty-nine births occurred in 37 women, 11 of them in clinical remission, and six thymectomized. The perinatal mortality was increased (P = 0.02) and induction of birth (P = 0.007) occurred more frequently. Protracted labor occurred more frequently in the target group (P = 0.03). One of the three children that died had Potter's syndrome. Both mothers with children who died were in complete clinical MG remission. One had previously given and one subsequently gave birth to a child with neonatal MG. The results indicate that complications in birth and pregnancy are not only related to clinical MG disease severity but to the underlying immunological dysfunction.

Circadian variations in sudden infant death syndrome: associations with maternal smoking, sleeping position and infections. The Nordic Epidemiological SIDS Study.

AIM: To study circadian variation in the sudden infant death syndrome (SIDS) and possible associations with risk factors for SIDS. METHODS: A questionnaire-based case-control study matched for place of birth, age and gender was conducted in Denmark, Norway and Sweden: The Nordic Epidemiological SIDS Study. The study comprised 244 SIDS victims and 869 control infants between September 1992 and August 1995. The main outcome was hour found dead. RESULTS: A significant circadian pattern was observed among the 242 SIDS victims with a known hour found dead, with a peak at 08.00-08.59 in the morning (n = 33). Of the SIDS victims, 12% were found dead at 00.00-05.59, 58% at 06.00-11.59, 21% at 12.00-17.59 and 9.0% at 18.00-23.59. When comparing night/morning SIDS and day/evening SIDS (found dead 00.00-11.59 and 12.00-23.59, respectively), the proportion of night/morning SIDS was high among infants of smoking mothers (81% vs 53%, p < 0.001), infants with a reported cold (82% vs 64%, p = 0.007) and infants sleeping side/supine (81% vs 60%, p < 0.001). No associations were observed between hour found dead and other sociodemographic risk factors for SIDS. Risk (odds ratio and 95% confidence interval) of night/morning SIDS and day/evening SIDS was 7.0 (4.5-10.9) and 1.5 (0.8-2.5), respectively, for maternal smoking, 2.2 (1.5-3.1) and 0.6 (0.3-1.3), respectively, if the infant had a reported cold, 3.7 (2.1-6.6) and 3.1 (1.1-8.4), respectively, if the infant was put to sleep in the side position (supine reference), and 11.0 (5.9-20.2) and 21.6 (7.6-60.8), respectively, if the infant was put to sleep in the prone position. CONCLUSION: The observed higher proportion of night/morning cases in SIDS if the mother smoked, if the infant was reported to have a cold and if the infant was sleeping side/supine may contribute to the understanding of some epidemiological characteristics of SIDS.