Iodine Nutrition in Children ≤2 years of Age in Norway.

BACKGROUND: As a component of the thyroid hormones (THs), iodine is vital for normal neurodevelopment during early life. However, both deficient and excess iodine may affect TH production, and data on iodine status in young children are scarce. OBJECTIVES: To describe iodine nutrition (iodine status and intake) in children ≤2 y of age in Innlandet County (Norway) and to describe the associations with maternal iodine nutrition. METHODS: A cross-sectional study was performed in a representative sample of mother-child pairs selected from 30 municipalities from November 2020 until October 2021. Iodine status [child urinary iodine concentration (UIC), maternal UIC, and breast milk iodine concentration (BMIC)] was measured. Child's iodine intake was estimated using 2 24-h dietary recalls (24-HR) and a food frequency questionnaire. The Multiple Source Method was used to estimate the usual iodine intake distributions from the 24-HR assessments. RESULTS: The median UIC in 333 children was 145 µg/L, indicating adequate iodine status according to the WHO cutoff (100 µg/L). The median usual iodine intake was 83 µg/d. Furthermore, 35% had suboptimal usual iodine intakes [below the proposed Estimated average requirement (72 µg/d)], whereas <1% had excessive usual iodine intakes [above the Upper intake level (200 µg/d)]. There was a positive correlation between children's iodine intake and BMIC (Spearman rank correlation coefficient r = 0.67, P < 0.001), and between children's UIC and BMIC (r = 0.43, P < 0.001), maternal UIC (r = 0.23, P = 0.001), and maternal iodine intake (r = 0.20, P = 0.004). CONCLUSION: Despite a median UIC above the cutoff for iodine sufficiency, more than a third of the children had suboptimal usual iodine intakes. Our findings suggest that many children will benefit from iodine fortification and that risk of iodine excess in this age group is low.

Inadequate Iodine Intake in Mothers of Young Children in Innlandet County, Norway.

Background: Iodine has an essential role in child growth and brain development. Thus, sufficient iodine intake is particularly important in women of childbearing age and lactating women. Objectives: This cross-sectional study aimed to describe iodine intake in a large random sample of mothers of young children (aged ≤2 y) living in Innlandet County, Norway. Methods: From November 2020 to October 2021, 355 mother-child pairs were recruited from public health care centers. Dietary data were obtained using two 24-h dietary recalls (24-HRs) per woman and an electronic FFQ. The Multiple Source Method was used to estimate the usual iodine intake from the 24-HR assessment. Results: Based on the 24-HRs, the median (P25, P75) usual iodine intake from food was 117 µg/d (88, 153) in nonlactating women and 129 µg/d (95, 176) in lactating women. The median (P25, P75) total usual iodine intake (from food combined with supplements) was 141 µg/d (97, 185) in nonlactating women and 153 µg/d (107, 227) in lactating women. Based on the 24-HRs, 62% of the women had a total iodine intake below the recommendations (150 µg/d in nonlactating women and 200 µg/d in lactating women), and 23% of them had an iodine intake below the average requirement (100 µg/d). The reported use of iodine-containing supplements was 21.4% in nonlactating women and 28.9% in lactating women. In regular users of iodine-containing supplements (n = 63), supplements contributed to an average of 172 µg/d of iodine. Among regular iodine supplement users, 81% reached the recommendations compared with 26% of nonsupplement users (n = 237). The iodine intake estimated by FFQ was substantially higher than that estimated by 24-HRs. Conclusions: Maternal iodine intake in Innlandet County was inadequate. This study confirms the need for action to improve iodine intake in Norway, particularly among women of childbearing age.

Vitamin B12 status in infancy and the effect of a vitamin B12 injection in infants with subclinical vitamin B12 deficiency: study protocol for a register-based randomised controlled trial.

INTRODUCTION: Vitamin B12 (cobalamin) is crucial for optimal child development and growth, yet deficiency is common worldwide. The aim of this study is twofold; (1) to describe vitamin B12 status and the status of other micronutrients in Norwegian infants, and (2) in a randomised controlled trial (RCT), investigate the effect of vitamin B12 supplementation on neurodevelopment in infants with subclinical vitamin B12 deficiency. METHODS AND ANALYSIS: Infant blood samples, collected at public healthcare clinics, are analysed for plasma cobalamin levels. Infants with plasma cobalamin <148 pmol/L are immediately treated with hydroxocobalamin and excluded from the RCT. Remaining infants (cobalamin ≥148 pmol/L) are randomly assigned (in a 1:1 ratio) to either a screening or a control group. In the screening group, baseline samples are immediately analysed for total homocysteine (tHcy), while in the control group, the baseline samples will be analysed after 12 months. Screening group infants with plasma tHcy >6.5 µmol/L, are given an intramuscular injection of hydroxocobalamin (400 µg). The primary outcomes are cognitive, language and motor development assessed using the Bayley Scales of Infant and Toddler Development at 12 months of age. ETHICS AND DISSEMINATION: The study has been approved by the Regional Committee for Medical and Health Research Ethics (ref: 186505). Investigators who meet the Vancouver requirements will be eligible for authorship and be responsible for dissemination of study findings. Results will extend current knowledge on consequences of subclinical vitamin B12 deficiency during infancy and may inform future infant feeding recommendations. TRIAL REGISTRATION NUMBER: NCT05005897.

Modifiable and non-modifiable risk factors for obstetric anal sphincter injury in a Norwegian Region: a case-control study.

BACKGROUND: Obstetric anal sphincter injury (OASI) is a common and severe complication of vaginal delivery and may have short- and long-term consequences, including anal incontinence, sexual dysfunction and reduced quality of life. The rate of OASI varies substantially between studies and national birth statistics, and a recent meta-analysis concluded that there is a need to identify unrecognized risk factors. Our aim was therefore to explore both potential modifiable and non-modifiable risk factors for OASI. METHODS: We performed a case-control study in a single center maternity clinic in South-Eastern Norway. Data were extracted retrospectively from an institutional birth registry. The main outcome measure was the occurrence of the woman's first-time 3rd or 4th degree perineal lesion (OASI) following singleton vaginal birth after 30 weeks' gestation. For each woman with OASI the first subsequent vaginal singleton delivery matched for parity was elected as control. The study population included 421 women with OASI and 421 matched controls who gave birth during 1990-2002. Potential risk factors for OASI were assessed by conditional logistic regression analyses. RESULTS: The mean incidence of OASI was 3.4% of vaginal deliveries, but it increased from 1.9% to 5.8% during the study period. In the final multivariate regression model, higher maternal age and birthweight for primiparous women, and higher birthweight for the multiparous women, were the only non-modifiable variables associated with OASI. Amniotomy was the strongest modifiable risk factor for OASI in both primi- (odds ratio [OR] 4.84; 95% confidence interval [CI] 2.60-9.02) and multiparous (OR 3.76; 95% CI 1.45-9.76) women, followed by augmentation with oxytocin (primiparous: OR 1.63; 95% CI 1.08-2.46, multiparous: OR 3.70; 95% CI 1.79-7.67). Vacuum extraction and forceps delivery were only significant risk factors in primiparous women (vacuum: OR 1.91; 95% CI 1.03-3.57, forceps: OR 2.37; 95% CI 1.14-4.92), and episiotomy in multiparous women (OR 2.64; 95% CI 1.36-5.14). CONCLUSIONS: Amniotomy may be an unrecognized independent modifiable risk factor for OASI and should be further investigated for its potential role in preventive strategies.

Antenatal thyroid hormone therapy and antithyroid drug use in Norway from 2004 to 2018.

Objective: Thyroid disease during pregnancy is associated with adverse pregnancy outcomes and suboptimal fetal development. During the last decades, guidelines for diagnosing thyroid disease during pregnancy have changed considerably and there has been increased awareness. This study aimed to describe the prevalence of thyroid disease treatment over time among pregnant women in Norway. Design: Nationwide register-based study. Methods: We combined historical data from the Medical Birth Registry of Norway and the Norwegian Prescription Database, identifying pregnant women using thyroid therapy from 2004 to 2018. Results: A total of 855,067 pregnancies were included in the analyses. The proportion of women using thyroid hormone replacement therapy during pregnancy increased from 1.46% (n = 800) in 2004 to 3.57% (n = 1940) in 2018. The proportion of women using antithyroid medications also increased from 0.04% (n = 20) in 2004 to 0.10% (n = 56). During these 15 years, the mean maternal age increased by 0.9 years. When adjusting for age, the risk for being on thyroid hormone replacement therapy during pregnancy increased by an average of 5% per year (odds ratio: 1.05, 95% CI: 1.05-1.05). Conclusion: During the recent 15 years, there has been a substantial increase in the use of thyroid hormone therapy in Norwegian pregnant women. We speculate that this could be due to an increased awareness in combination with overdiagnosis because of inappropriate diagnostic criteria. To truly understand the possible causes and consequences of this development, further research is warranted.

Health-Related Behaviors in Adolescents Mediate the Association between Subjective Social Status and Body Mass Index.

The aim of this study was to explore the association between adolescent subjective social status (SSS) and body mass index (BMI) at two different time points and to determine whether this association was mediated by health-related behaviors. In 2002 (n = 1596) and 2017 (n = 1534), tenth-grade students (15-16 years old) in schools in the District of Oppland, Norway, completed a survey. Four categories of perceived family economy were measured as SSS, and structural equation modeling was performed, including a latent variable for unhealthy behavior derived from cigarette smoking, snuff-use, and alcohol-drinking as well as dietary and exercise as mediators. No linear association was found between SSS and BMI in 2002 (standardized ß -0.02, (95% confidence interval (CI) -0.07, 0.03)). However, an association was present in 2017 (standardized ß -0.05 (95% CI -0.10, -0.001)), indicating that BMI decreased by 0.05 standard deviations (0.05 × 3.1 = 0.16 BMI unit) for every one-category increase in SSS. This association was mediated by exercise (standardized ß -0.013 (95% CI -0.02, -0.004) and unhealthy behavior (standardized ß -0.009 (95% CI -0.002, -0.04)). In conclusion, a direct association between SSS and BMI was found in 2017 in this repeated cross-sectional survey of 15-16-year-old Norwegian adolescents. This association was mediated through health-related behavior.

Emergency cesarean section among women in Robson groups one and three: A comparison study of immigrant and Norwegian women giving birth in a low-risk maternity hospital in Norway.

Researchers have shown that some immigrant groups have an increased risk of emergency cesarean section. The authors' aim was to examine the differences in emergency cesarean section rates among immigrant women in Norway with low obstetric risks by using the Robson classification system. We performed secondary analysis on a Norwegian cohort study, where 10,125 women were classified in Robson groups one and three. Women from East, Southeast, and Central Asia, and from Africa had a higher risk of emergency cesarean section. The Robson classification system was a useful tool in comparing cesarean section rates between immigrant groups and host country populations.

Obstetric Outcomes of First- and Second-Generation Pakistani Immigrants: A Comparison Study at a Low-Risk Maternity Ward in Norway.

This population-based study compares obstetric outcomes of first- and second-generation Pakistani immigrants and ethnic Norwegians who gave birth at the low-risk maternity ward in Baerum Hospital in Norway from 2006 to 2013. We hypothesized that second-generation Pakistani immigrants are more similar to the ethnic Norwegians because of increased acculturation. Outcome measures were labor onset, epidural analgesia, labor dystocia, episiotomy, vaginal/operative delivery, postpartum hemorrhage, preterm birth, birth weight, transfer to a neonatal intensive care unit, and neonatal jaundice. Compared to first-generation Pakistani immigrants, the second-generation reported more health issues before pregnancy, and they had a higher proportion of preterm births compared to Norwegians. Newborns of first-generation immigrants were more often transferred to a neonatal intensive care compared to Norwegian newborns. Few intergenerational differences in the obstetric outcomes were found between the two generations. A high prevalence of consanguinity in second-generation immigrants suggests the maintenance of a traditional Pakistani marriage pattern.

Immigrants from conflict-zone countries: an observational comparison study of obstetric outcomes in a low-risk maternity ward in Norway.

BACKGROUND: Immigrants have higher risks for some adverse obstetric outcomes. Furthermore, refugees are reported to be the most vulnerable group. This study compared obstetric outcomes between immigrant women originating from conflict-zone countries and ethnic Norwegians who gave birth in a low-risk setting. METHODS: This was a population-based study linking the Medical Birth Registry of Norway to Statistics Norway. The study included the first registered birth during the study period of women from Somalia (n = 278), Iraq (n = 166), Afghanistan (n = 71), and Kosovo (n = 67) and ethnic Norwegians (n = 6826) at Baerum Hospital from 2006-2010. Background characteristics and obstetric outcomes of each immigrant group were compared with ethnic Norwegians with respect to proportions and risks calculated by logistic regression models. RESULTS: In total, 7408 women and their births were analyzed. Women from Somalia were most at risk for adverse obstetric outcomes. Compared with ethnic Norwegians, they had increased odds ratios (OR) for emergency cesarean section (OR 1.81, CI 1.17-2.80), postterm birth (OR 1.93, CI 1.29-2.90), meconium-stained liquor (OR 2.39, CI 1.76-3.25), and having a small-for-gestational-age infant (OR 3.97, CI 2.73-5.77). They had a reduced OR for having epidural analgesia (OR 0.40, CI 0.28-0.56) and a large-for-gestational-age infant (OR 0.32, CI 0.16-0.64). Women from Iraq and Afghanistan had increased risk of having a small-for-gestational-age infant with OR of 2.21 (CI 1.36-3.60) and 2.77 (CI 1.42-5.39), respectively. Iraqi women also had reduced odds ratio of having a large-for-gestational-age infant (OR 0.35, CI 0.15-0.83). Women from Kosovo did not differ from ethnic Norwegians in any of the outcomes we tested. CONCLUSIONS: Even in our low-risk maternity ward, women originating from Somalia were at the greatest risk for adverse obstetric outcomes in the compared groups. We could not find the same risk among the other immigrant women, also originating from conflict-zone countries. Several factors may influence these findings, and this study suggests that immigrant women from Somalia need more targeted care during pregnancy and childbirth.

Higher risk for adverse obstetric outcomes among immigrants of African and Asian descent: a comparison study at a low-risk maternity hospital in Norway.

BACKGROUND: Immigrants have higher risks for some adverse obstetric outcomes, and 40 percent of women giving birth at the low-risk maternity ward in Baerum Hospital, Norway, are immigrants. This study compared obstetric outcomes between immigrants and ethnic Norwegians giving birth in a low-risk setting. METHODS: This was a population-based study linking the Medical Birth Registry of Norway to Statistics Norway. The study included the first registered birth during the study period to immigrant and ethnic Norwegian women at Baerum Hospital from 2006 to 2010. The main outcome measures were onset of labor, operative vaginal delivery, cesarean delivery, episiotomy, postpartum bleeding > 500 mL, epidural analgesia, labor dystocia, gestational age, meconium-stained liquor, 5-minute Apgar score, birthweight, and transfer to a neonatal intensive care unit. RESULTS: A total of 11,540 women originating from 141 countries were divided into seven groups. Compared with Norwegians, women from East, Southeast, and Central Asia had increased risk for operative vaginal delivery, postpartum bleeding, and low Apgar score. The African women had increased risk for postterm birth, meconium-stained liquor, episiotomy, operative vaginal delivery, emergency cesarean delivery, postpartum bleeding, low Apgar score, and low birthweight. Women from South and Western Asia had increased risk for low birthweight. CONCLUSION: Obstetric outcomes of immigrants differ significantly from those of Norwegians, even in a low-risk maternity unit. Thus, immigrant women would benefit from more targeted care during pregnancy and childbirth, even in low-risk settings.