Paternal and maternal birthweight and offspring risk of macrosomia at term gestations: A nationwide population study.

BACKGROUND: There is a paucity of data on whether parents' macrosomia (birthweight ≥4500 g) status influences the risk of macrosomia in the offspring. The role of maternal overweight in the generational effect of macrosomia is not known. OBJECTIVE: To estimate the risk of macrosomia by parental birthweight at term and evaluate if this risk varied with maternal body mass index (BMI, kg/m2) early in pregnancy. METHODS: We used data from the Medical Birth Registry of Norway on all singleton term births (37-42 gestational weeks) during 1967-2017. The primary exposure was parental macrosomia, and the outcome was macrosomia in the second generation. The secondary exposure was maternal BMI. We used binomial regression to calculate relative risk (RR) with a 95% confidence interval. We assessed potential unmeasured confounding and selection bias using a probabilistic bias analysis and performed analyses with and without imputation for variables with missing values. RESULTS: The data included 647,957 singleton parent-offspring trios born at term. The prevalence of macrosomia was 3.2% (n = 41,396) in the parental generation and 4.0% (n = 25,673) in the offspring generation. Macrosomia in parents was associated with an increased risk of macrosomia in offspring, with the RR for both parents were born macrosomic being 6.53 (95% confidence interval [CI] 5.31, 8.05), only mother macrosomic 3.37 (95% CI 3.17, 3.57) and only father macrosomic RR 2.22 (95% CI 2.12, 2.33). These risks increased by maternal BMI in early pregnancy: if both parents were born macrosomic, 17% of infants were macrosomic among mothers with normal BMI. If both parents were macrosomic and the mothers were obese, 31% of offspring were macrosomic. Macrosomia-related adverse outcomes did not differ with parental macrosomia status. CONCLUSIONS: Parents' weight at birth and maternal BMI appear to be strongly associated with macrosomia in the offspring delivered at term gestations.

Reproductive outcomes in women and men conceived by assisted reproductive technologies in Norway: prospective registry based study.

Objectives: To determine whether the perinatal outcomes of women or men who were conceived by assisted reproductive technologies are different compared with their peers who were naturally conceived. Design: Prospective registry based study. Setting: Medical Birth Registry of Norway. Participants: People born in Norway between 1984 and 2002 with a registered pregnancy by the end of 2021. Exposure: People who were conceived by assisted reproductive technologies and have had a registered pregnancy. Main outcome measures: Comparing pregnancies and births of people who were conceived by assisted reproductive technologies and people who were naturally conceived, we assessed mean birth weight, gestational age, and placental weight by linear regression, additionally, the odds of congenital malformations, a low 5 min Apgar score (<7), transfer to a neonatal intensive care unit, delivery by caesarean section, use of assisted reproductive technologies, hypertensive disorders of pregnancy and pre-eclampsia, preterm birth, and offspring sex, by logistic regression. The occurrence of any registered pregnancy from people aged 14 years until age at the end of follow-up was assessed using Cox proportional regression for both groups. Results: Among 1 092 151 people born in Norway from 1984 to 2002, 180 652 were registered at least once as mothers, and 137 530 as fathers. Of these, 399 men and 553 women were conceived by assisted reproductive technologies. People who were conceived by assisted reproductive technologies had little evidence of increased risk of adverse outcomes in their own pregnancies, increased use of assisted reproductive technologies, or any difference in mean birth weight, placental weight, or gestational age. The only exception was for an increased risk of the neonate having a low Apgar score at 5 min (adjusted odds ratio 1.86 (95% confidence interval 1.20 to 2.89)) among women who were conceived by assisted reproductive technologies. Odds were slightly decreased of having a boy among mothers conceived by assisted reproductive technologies (odds ratio 0.79 (95% confidence interval 0.67 to 0.93)). People conceived by assisted reproductive technologies were slightly less likely to have a registered pregnancy within the follow-up period (women, adjusted hazard ratio 0.88 (95% CI 0.81 to 0.96); men, 0.91 (0.83 to 1.01)). Conclusions: People conceived by assisted reproductive technologies were not at increased risk of obstetric or perinatal complications when becoming parents. The proportion of people conceived by assisted reproductive technologies with a registered pregnancy was lower than among people who were naturally conceived, but a longer follow-up is required to fully assess their fertility and reproductive history.

Health at age 17 in Norwegian adolescents: Mental and physical status in the national cohort born in 2001.

AIMS: We present self-reported data on physical and mental health at age 17 years from 82% of Norwegians born in 2001. METHODS: In Norway, the Armed Forces require that each resident who reaches the age of 17 years completes a self-administered declaration of health that is used for military selection. The declaration collects information on height and weight, various clinically diagnosed diseases, mental and behavioural disorders, and other health conditions where clinical diagnosis is not required. In 2018, there were 65,913 adolescents born in 2001 living in Norway, of whom 10,223 were exempt from completing the declaration; declarations were therefore sent to 55,690 participants. We included 54,132 participants who completed the declaration (response rate 97.2%): 27,220 male and 26,912 female respondents. RESULTS: We found that 18% of male and 28% of female respondents reported at least one clinically diagnosed disease, mental disorder or behavioural disorder. Among health condition where clinical diagnosis was not required, 19% of male and 37% of female respondents reported anxiety/depression affecting daily life and 10 versus 18% reported migraines/recurring headaches. The respondents probably represent the healthiest part of the total cohort of 17-year-old Norwegians because those who are exempt from completing the declaration are already considered unfit for military service. CONCLUSIONS: These data represent a rich resource for further research. Similar data exist for the birth cohorts in 1993-2003. We encourage further research that can help decision-makers identify areas of concern that should be targeted for interventions.

Association of COVID-19 Vaccination During Pregnancy With Incidence of SARS-CoV-2 Infection in Infants.

Importance: Pregnant women are recommended to receive COVID-19 vaccination to reduce risk of severe COVID-19. Whether vaccination during pregnancy also provides passive protection to infants after birth remains unclear. Objective: To determine whether COVID-19 vaccination in pregnancy was associated with reduced risk of COVID-19 in infants up to age 4 months during COVID-19 pandemic periods dominated by Delta and Omicron variants. Design, Setting, and Participants: This nationwide, register-based cohort study included all live-born infants born in Norway between September 1, 2021, and February 28, 2022. Exposures: Maternal messenger RNA COVID-19 vaccination during second or third trimester compared with no vaccination before or during pregnancy. Main Outcomes and Measures: The risk of a positive polymerase chain reaction test result for SARS-CoV-2 during an infant's first 4 months of life by maternal vaccination status during pregnancy with either dose 2 or 3 was estimated, as stratified by periods dominated by the Delta variant (between September 1 and December 31, 2021) or Omicron variant (after January 1, 2022, to the end of follow-up on April 4, 2022). A Cox proportional hazard regression was used, adjusting for maternal age, parity, education, maternal country of birth, and county of residence. Results: Of 21 643 live-born infants, 9739 (45.0%) were born to women who received a second or third dose of a COVID-19 vaccine during pregnancy. The first 4 months of life incidence rate of a positive test for SARS-CoV-2 was 5.8 per 10 000 follow-up days. Infants of mothers vaccinated during pregnancy had a lower risk of a positive test compared with infants of unvaccinated mothers and lower risk during the Delta variant-dominated period (incidence rate, 1.2 vs 3.0 per 10 000 follow-up days; adjusted hazard ratio, 0.29; 95% CI, 0.19-0.46) compared with the Omicron period (incidence rate, 7.0 vs 10.9 per 10 000 follow-up days; adjusted hazard ratio, 0.67; 95% CI, 0.57-0.79). Conclusions and Relevance: The results of this Norwegian population-based cohort study suggested a lower risk of a positive test for SARS-CoV-2 during the first 4 months of life among infants born to mothers who were vaccinated during pregnancy. Maternal COVID-19 vaccination may provide passive protection to young infants, for whom COVID-19 vaccines are currently not available.

Association between work situation and life satisfaction during the COVID-19 pandemic: prospective cohort study in Norway.

OBJECTIVES: To estimate the impact of being laid off from work, having to work from home or having been diagnosed with COVID-19 on self-reported satisfaction with life. DESIGN: Nationwide population-based cohort study. SETTING: Norway. PARTICIPANTS: We followed more than 80 000 participants in an ongoing cohort study, the Norwegian Mother, Father and Child Cohort Study (MoBa), during the COVID-19 pandemic. We analysed current life satisfaction in April and again in September/October 2020 for subjects whose work situation and infection status had changed. MAIN OUTCOME MEASURES: Self-reported satisfaction with life, using a scale from 0 (worst) to 10 (best). We analysed the scale both continuously and as a binary variable (

Social and life skills in adolescents who have self-harmed: analysis of survey responses from a national sample of adolescents in Norway.

OBJECTIVE: Social and life skills (SLS) may be important in the prevention and treatment of self-harm, but few studies have described this relationship. We examined three components of SLS in adolescents who reported self-harm that was, according to themselves, diagnosed by a clinician. DESIGN: Cross-sectional. SETTING: National screening prior to military service. PARTICIPANTS: 176 284 residents of Norway born in 1999-2001 received a declaration of health. We included 171 486 individuals (84 153 (49%) women and 87 333 (51%) men) who were 17 (n=1 67 855) or 18 years of age (n=3631) when they completed the declaration. OUTCOME MEASURE: The main outcome was clinically diagnosed self-harm, defined as self-harm that the adolescents themselves stated had been diagnosed by a clinician. Components of SLS were social interactions; coping strategies; and emotional regulation/aggression. The association between SLS and self-reported clinically diagnosed self-harm was assessed in hierarchical multiple regression models controlling for sex; school absence; and feelings of emotional pain. RESULTS: Three percent (n=5507) of the adolescents reported clinically diagnosed self-harm. The three components of SLS together added little to the prediction of clinically diagnosed self-harm (∆R2=0.02). After controlling for school absence and emotional pain, emotional regulation/aggression was the only SLS-component that was independently associated with clinically diagnosed self-harm (OR 1.33, 95% CI 1.31 to 1.36). The young men who said they had been clinically diagnosed for self-harm scored slightly worse on social interactions (Hedge's g (g) = -0.13, p<0.001) and emotional regulation/aggression (g = -0.18, p<0.001) than the young women in this group. CONCLUSION: Young women and young men who reported clinically diagnosed self-harm had more problems with emotional regulation/aggression than other adolescents, but did not have worse social interactions or coping strategies.

Stumped by the Hump: The Curious Rise and Fall of Norwegian Birthweights, 1991-2007.

BACKGROUND: There was a distinct rise in mean birthweights in Norway starting in 1991 that plateaued in 1996-2002 and then declined to previous levels. We investigated whether these changes corresponded to trends in neonatal mortality or other birthweight-associated pregnancy outcomes. We also explored known predictors of birthweight and examined whether these could explain the birthweight trends. METHODS: We calculated mean birthweight for all live births in Norway in each year from 1982 to 2016, together with annual neonatal mortality and proportion of infants born preterm, or with low Apgar score. We stratified mean birthweight over time by factors including parity, gestational age, and Scandinavian versus non-Scandinavian origin of mother, to test robustness of the pattern. In addition, we used multivariable linear regression to obtain adjusted estimates for mean birthweight per year. RESULTS: A 50-g rise and fall of mean birthweights during a 25-year period was not accompanied by corresponding changes in neonatal mortality, preterm births, or Apgar scores. The distinct hump pattern was restricted to term births and was not apparent among infants of mothers born outside Scandinavia. We saw a similar pattern for Sweden but not Finland. Known predictors of birthweight (such as parity, mode of onset of delivery, and marital status) did not explain the hump. CONCLUSIONS: A distinct temporal hump in mean birthweight among Norwegian term births had no obvious explanations. Furthermore, these fluctuations in birthweight were not associated indirectly with adverse outcomes in measures of infant health.