Maternal Fecal Microbiota Transplantation in Cesarean-Born Infants Rapidly Restores Normal Gut Microbial Development: A Proof-of-Concept Study.

Infants born by vaginal delivery are colonized with maternal fecal microbes. Cesarean section (CS) birth disturbs mother-to-neonate transmission. In this study (NCT03568734), we evaluated whether disturbed intestinal microbiota development could be restored in term CS-born infants by postnatal, orally delivered fecal microbiota transplantation (FMT). We recruited 17 mothers, of whom seven were selected after careful screening. Their infants received a diluted fecal sample from their own mothers, taken 3 weeks prior to delivery. All seven infants had an uneventful clinical course during the 3-month follow-up and showed no adverse effects. The temporal development of the fecal microbiota composition of FMT-treated CS-born infants no longer resembled that of untreated CS-born infants but showed significant similarity to that of vaginally born infants. This proof-of-concept study demonstrates that the intestinal microbiota of CS-born infants can be restored postnatally by maternal FMT. However, this should only be done after careful clinical and microbiological screening.

Albumin and Cardioprotection in On-Pump Cardiac Surgery-A Post Hoc Analysis of a Randomized Trial.

OBJECTIVES: To study the quantitative potency of plasma albumin on cardioprotection in terms of creatinine kinase-myocardial band mass (CK-MBm) in on-pump cardiac surgery. DESIGN: Post hoc analysis of a double-blinded randomized clinical trial. SETTING: Single-center study in the Helsinki University Hospital. PARTICIPANTS: A total of 1,386 adult on-pump cardiac surgical patients. INTERVENTION: Administration of 4% albumin (n = 693) or Ringers acetate (n = 693) for cardiopulmonary bypass priming and volume replacement intraoperatively and postoperatively during the first 24 hours. MEASUREMENTS AND MAIN RESULTS: Albumin concentration was measured preoperatively and intraoperatively (after protamine administration), and CK-MBm on the first postoperative morning. Multivariate linear regression analyses were measured in the whole cohort and the Ringer group. Plasma albumin concentration did not differ between the groups preoperatively (Ringer v albumin: 38.3 ± 5.0 g/L v 38.6 ± 4.5 g/L; p = 0.171) but differed intraoperatively (29.5 ± 5.2 g/L v 41.5 ± 6.0 g/L; p < 0.001). Creatinine kinase-myocardial band mass was higher in the Ringer (32.0 ± 34.8 µg/L) than in the albumin group (24.3 ± 33.0 µg/L) (p < 0.001). Aortic cross-clamping time associated with CK-MBm in the whole cohort (standardized ß = 0.376 [95% CI 0.315-0.437], p < 0.001) and the Ringer group (ß = 0.363 [0.273-0.452]; p < 0.001). Albumin administration in the whole cohort (ß = -0.156 [-0.201 to -0.111]; p < 0.001) and high intraoperative albumin concentration in the Ringer group (ß = -0.07 [-0.140 to -0.003]; p = 0.04) associated with reduced CK-MBm. Compared with ischemia-induced increase in CK-MBm, albumin's potency to reduce CK-MBm was 41% in the whole cohort (ß-value ratio of -0.156/0.376) and 19% in the Ringer group (ß-value ratio of -0.07/0.363). CONCLUSION: Both endogenous and exogenous albumin appear to be cardioprotective regarding CK-MBm release in on-pump cardiac surgery.

Highly pathogenic avian influenza A(H5N1) virus infections on fur farms connected to mass mortalities of black-headed gulls, Finland, July to October 2023.

Highly pathogenic avian influenza (HPAI) has caused widespread mortality in both wild and domestic birds in Europe 2020-2023. In July 2023, HPAI A(H5N1) was detected on 27 fur farms in Finland. In total, infections in silver and blue foxes, American minks and raccoon dogs were confirmed by RT-PCR. The pathological findings in the animals include widespread inflammatory lesions in the lungs, brain and liver, indicating efficient systemic dissemination of the virus. Phylogenetic analysis of Finnish A(H5N1) strains from fur animals and wild birds has identified three clusters (Finland I-III), and molecular analyses revealed emergence of mutations known to facilitate viral adaptation to mammals in the PB2 and NA proteins. Findings of avian influenza in fur animals were spatially and temporally connected with mass mortalities in wild birds. The mechanisms of virus transmission within and between farms have not been conclusively identified, but several different routes relating to limited biosecurity on the farms are implicated. The outbreak was managed in close collaboration between animal and human health authorities to mitigate and monitor the impact for both animal and human health.

Face mask recommendations in schools did not impact COVID-19 incidence among 10-12-year-olds in Finland - joinpoint regression analysis.

BACKGROUND: In autumn 2021 in Finland, a recommendation to use face masks was implemented nationwide in schools for pupils ages 12 years and above. While national guidelines were in form of recommendations, cities implemented mandatory masking in schools. Some cities extended this mandate for younger pupils as well. Our aim was to compare COVID-19 incidence among 10-12-year-olds between cities with different recommendations on the use of face masks in schools. METHODS: COVID-19 case numbers, defined as positive laboratory verified SARS-CoV-2 test results, were obtained from the National Infectious Disease Registry (NIDR) of the Finnish Institute for Health and Welfare. Helsinki, Turku and Tampere were selected for comparison since the baseline COVID-19 incidence in the cities had been similar in August and September 2021. Helsinki and Tampere implemented the national recommendation on face mask use at schools, while Turku extended this to include those 10 years old and above, starting from the beginning of semester in early August. Age groups of 7-9-year-olds, 10-12-year-olds and 30-49-year-olds were included in the statistical analysis and moving averages of 14-day incidences per 100 000 inhabitants were used as a dependent variable. Joinpoint regression was used to estimate average percent changes (APC) and average daily percent changes (ADPC) in the 14-day incidences. Differences in the ADPC values between the cities were compared in one-month periods. We also calculated cumulative incidences from the beginning of August to the end of November in the cities by age group. RESULTS: In August, the ADPC was highest in Turku (3.9) and lowest in Tampere (2.0), while in September, the ADPC was highest in Turku (-0.3) and lowest in Helsinki (-3.2) among 10-12-year-olds. In October, the ADPC was highest in Helsinki (2.1) and lowest in Turku (-0.2) and in November, the ADPC was highest in Turku (4.1) and lowest in Tampere (-0.5) among 10-12-year-olds. We also calculated cumulative incidences from the beginning of August to the end of November in the cities by age groups of 7-9 years, 10-12 years, and 30-49 years. The cumulative incidence was highest in Turku in all age groups and lowest in Tampere. CONCLUSIONS: According to our analysis, no additional effect was gained from mandating face masks, based on comparisons between the cities and between the age groups of the unvaccinated children (10-12 years versus 7-9 years).

When schools were open for in-person teaching during the COVID-19 pandemic - the nordic experience on control measures and transmission in schools during the delta wave.

BACKGROUND: Extensive measures to control spread of SARS-CoV-2 have led to limited access to education for millions of children and adolescents during the COVID-19 pandemic. Education and access to schools is vital for children and adolescents' learning, health, and wellbeing. Based on high vaccine uptake and low incidence levels, the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) decided to start the academic year 2021/22 with schools open for in-person teaching and moderate mitigation measures. We describe trends in SARS-CoV-2 infections and vaccination coverage among students during the first 12 weeks of the fall semester. METHODS: In this multinational, retrospective, observational study, we have used surveillance and registry data from each of the Nordic countries to describe vaccine uptake (≥12 years), infection incidence (whole population) and transmission of SARS-CoV-2 among students. The study period, week 30 to 41 (Jul 26th - Oct 17th), represents the autumn semester from immediately before school started until fall break. In addition, we collected information on mitigation measures applied by the respective countries. RESULTS: There were slight variations between the countries regarding existing infection prevention and control (IPC) measures, testing strategies and vaccination start-up among adolescents. All countries had high vaccine uptake in the adult population, while uptake varied more in the younger age groups. Incidence in the school-aged population differed between countries and seemed to be influenced by both vaccine uptake and test activity. Infection clusters among school-aged children were described for Denmark and Norway, and the number of clusters per week reflected the incidence trend of the country. Most events consisted of only 1-2 cases. Larger clusters appeared more frequently in the higher grades in Norway and in lower grades in Denmark. CONCLUSION: Data from the Nordic countries indicate that vaccination of adults and adolescents, in addition to mitigation measures, enabled full in-person learning. As SARS-CoV-2 infection does not represent a severe medical risk for most children as previously thought, measures targeting this group should be carefully adjusted and kept at a minimum. Our data add to the evidence on incidence and transmission of SARS-CoV-2 among students in schools open for in-person teaching, and may be valuable for decision makers worldwide.

Highly pathogenic avian influenza A(H5N1) virus infection on multiple fur farms in the South and Central Ostrobothnia regions of Finland, July 2023.

Since mid-July 2023, an outbreak caused by highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b genotype BB is ongoing among farmed animals in South and Central Ostrobothnia, Finland. Infections in foxes, American minks and raccoon dogs have been confirmed on 20 farms. Genetic analysis suggests introductions from wild birds scavenging for food in farm areas. Investigations point to direct transmission between animals. While no human infections have been detected, control measures are being implemented to limit spread and human exposure.

Introduction and Rapid Spread of SARS-CoV-2 Omicron Variant and Dynamics of BA.1 and BA.1.1 Sublineages, Finland, December 2021.

Multiple introductions of SARS-COV-2 Omicron variant BA.1 and BA.1.1. lineages to Finland were detected in early December 2021. Within 3 weeks, Omicron overtook Delta as the most common variant in the capital region. Sequence analysis demonstrated the emergence and spread through community transmission of a large cluster of BA.1.1 virus.

Election promises on children's wellbeing and health 2015 to 2021 - a study of Finnish voting advice applications database.

BACKGROUND: According to the UN Convention on the Rights of the Child, children's views should be heard in policymaking. But it remains unclear to what extent children's wellbeing is considered in election promises. METHODS: We investigated the extent to which Finnish political candidates consider children and their wellbeing in their election promises. We used YLE, the national broadcaster's voting advice application database, and analysed some 35,000 politicians' election promises made in the 2015 and 2019 parliamentary and the 2017 and 2021 municipal elections. We calculated the proportion of candidates who mentioned children and examined the content of the election promises in which children were mentioned. Logistic regression models were used to examine the role of the background of the characteristics of candidates. RESULTS: In the 2015 and 2019 elections, some 12% and 19% of candidates, respectively, mentioned children in their election promises. The figures for the 2017 and 2021 municipal elections were higher at 19% and 24%, respectively. In the 2021 election, the candidates considering children in their election promises were younger and had higher education qualifications. Inspection of a random set of 350 promises indicated that common issues mentioned in respect of children were education and hobby activities. Concrete proposals to improve the wellbeing of children were rarely put forward. CONCLUSIONS: Political candidates are increasingly considering children in their election promises but concrete proposals to improve the wellbeing and health of children are rare. Effective policy solutions to improve the health of children should be discussed in election debates.

Transplantation of maternal intestinal flora to the newborn after elective cesarean section (SECFLOR): study protocol for a double blinded randomized controlled trial.

BACKGROUND: A complication of elective cesarean section (CS) delivery is its interference with the normal intestinal colonization of the infant, affecting the immune and metabolic signaling in early life- a process that has been associated with long-term morbidity, such as allergy and diabetes. We evaluate, in CS-delivered infants, whether the normal intestinal microbiome and its early life development can be restored by immediate postnatal transfer of maternal fecal microbiota (FMT) to the newborn, and how this procedure influences the maturation of the immune system. METHODS: Sixty healthy mothers with planned elective CS are recruited and screened thoroughly for infections. A maternal fecal sample is taken prior to delivery and processed according to a transplantation protocol. After double blinded randomization, half of the newborns will receive a diluted aliquot of their own mother's stool orally administered in breast milk during the first feeding while the other half will be similarly treated with a placebo. The infants are clinically followed, and fecal samples are gathered weekly until the age of 4 weeks, then at the ages of 8 weeks, 3, 6, 12 and 24 months. The parents fill in questionnaires until the age of 24 months. Blood samples are taken at the age of 2-3 days and 3, 6, 12 and 24 months to assess development of major immune cell populations and plasma proteins throughout the first years of life. DISCUSSION: This is the first study to assess long-time effects on the intestinal microbiome and the development of immune system of a maternal fecal transplant given to term infants born by CS. TRIAL REGISTRATION: ClinicalTrials.gov NCT04173208 , registration date 21.11.2019.

Decrease in paediatric emergency room visits during the COVID-19 pandemic restrictions: A population-based study.

AIM: To investigate paediatric emergency room (ER) visits to evaluate the immediate health effects of COVID-19 pandemic restrictions on children. METHODS: We retrospectively examined paediatric ER visits in the Helsinki University Hospital (HUH) district during the first wave of the pandemic (1 March to 31 May 2020), and a 2-month period immediately before and after. These periods were compared to the corresponding time periods in 2015-2019 ('reference period'). RESULTS: The total number of ER visits decreased by 23.4% (mean 6474 during the reference period, 4960 during the pandemic period (incidence rate ratio [IRR] 0.75, 95% confidence interval 0.72-0.77; p < 0.001). This was due to a decrease in visits related to infectious diseases; visits due to surgical reasons did not decrease. The amount or proportion of patients triaged to the most urgent class (Emergency Severity Index 1) did not increase. Paediatric ER visits returned to baseline after lifting of restrictions. CONCLUSIONS: Although paediatric ER visits substantially decreased during the pandemic restrictions, children seen at the ER were not more severely ill. Our results do not indicate immediate detrimental health effects of pandemic control measures on children.

Incidence Trends for SARS-CoV-2 Alpha and Beta Variants, Finland, Spring 2021.

Severe acute respiratory syndrome coronavirus 2 Alpha and Beta variants became dominant in Finland in spring 2021 but had diminished by summer. We used phylogenetic clustering to identify sources of spreading. We found that outbreaks were mostly seeded by a few introductions, highlighting the importance of surveillance and prevention policies.

Glucocorticoids, sodium transport mediators, and respiratory distress syndrome in preterm infants.

BACKGROUND: Antenatal glucocorticoids (GCs) reduce respiratory distress syndrome (RDS) in preterm infants and are associated with reduced lung liquid content. Our aim was to assess whether airway gene expression of mediators of pulmonary epithelial sodium and liquid absorption, and further, respiratory morbidity, associate with cord blood GC concentrations. METHODS: The study included 64 infants delivered <32 weeks gestation. Cortisol and betamethasone in umbilical cord blood were quantified with liquid chromatography-tandem mass spectrometry. The total GC concentration was calculated. Gene expression of the epithelial sodium channel (ENaC), Na,K-ATPase, and serum- and GC-inducible kinase 1 at <2 h and at 1 day postnatally in nasal epithelial cell samples was quantified with reverse transcription-polymerase chain reaction. The mean oxygen supplementation during the first 72 h was calculated. RESULTS: Concentrations of cord blood betamethasone and total GC were significantly lower in infants with RDS and correlated with mean oxygen supplementation. Expression of αENaC and α1- and ß1Na,K-ATPase at <2 h correlated with betamethasone and total GC concentrations. Expression of Na,K-ATPase was lower in infants with RDS. CONCLUSION: Enhancement of lung liquid absorption via increased expression of sodium transporters may contribute to the beneficial pulmonary effects of antenatal GCs. IMPACT: RDS is related to lower umbilical cord blood GC concentrations and lower airway expression of sodium transporters. In addition to the timing of antenatal GC treatment, resulting concentrations may be of importance in preventing RDS. Induction of sodium transport may be a factor contributing to the pulmonary response to antenatal GCs.

Closing lower secondary schools had no impact on COVID-19 incidence in 13-15-year-olds in Finland.

School lockdowns have been widely used to control the COVID-19 pandemic. However, these lockdowns may have a significant negative impact on the lives of young people. In this study, we have evaluated the impact of closing lower secondary schools for COVID-19 incidence in 13-15-year-olds in Finland, in a situation where restrictions and recommendation of social distancing were implemented uniformly in the entire country. COVID-19 case numbers were obtained from the National Infectious Disease Registry (NIDR) of the Finnish Institute for Health and Welfare, in which clinical microbiology laboratories report all positive SARS-CoV-2 tests with unique identifiers in a timely manner. The NIDR is linked to population data registry, enabling calculation of incidences. We estimated the differences in trends between areas with both restaurant and lower secondary school closures and areas with only restaurant closures in different age groups by using joinpoint regression. We also estimated the differences in trends between age groups. Based on our analysis, closing lower secondary schools had no impact on COVID-19 incidence among 13-15-year-olds. No significant changes on COVID-19 incidence were observed in other age groups either.

Multi-inflammatory syndrome and Kawasaki disease in children during the COVID-19 pandemic: A nationwide register-based study and time series analysis.

AIM: We investigated whether the ongoing COVID-19 pandemic was associated with the occurrence of Kawasaki disease or with multi-inflammatory syndrome in children (MIS-C). METHODS: This national Finnish register-based study was based on laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, MIS-C and Kawasaki disease cases. We performed a time series analysis on the occurrence of Kawasaki disease in 2016-2020. RESULTS: In 2020, there were 5170 laboratory-confirmed COVID-19 cases in children under 18 years of age and five fulfilled the MIS-C case definition. The occurrence of MIS-C was 0.97 per 1000 (95% confidence interval: 0.31-2.26) laboratory-confirmed SARS-CoV-2 infections in children. Our time series analysis showed that Kawasaki disease cases decreased during the COVID-19 pandemic. The seasonally adjusted incidence rate ratio was 0.49 (95% confidence interval: 0.32-0.74) when it was compared to pre-pandemic levels. This coincided with a reduced occurrence of respiratory infections, due to social distancing in the population. CONCLUSION: This nationwide register-based study found that MIS-C was a rare complication of the SARS-CoV-2 infection. The occurrence of Kawasaki disease and respiratory infections decreased during the pandemic. This suggests that transmissible microbes may play an important role in Kawasaki disease and social distancing may have a protective effect.

Characteristics of SARS-CoV-2 variants of concern B.1.1.7, B.1.351 or P.1: data from seven EU/EEA countries, weeks 38/2020 to 10/2021.

We compared 19,207 cases of SARS-CoV-2 variant B.1.1.7/S gene target failure (SGTF), 436 B.1.351 and 352 P.1 to non-variant cases reported by seven European countries. COVID-19 cases with these variants had significantly higher adjusted odds ratios for hospitalisation (B.1.1.7/SGTF: 1.7, 95% confidence interval (CI): 1.0-2.9; B.1.351: 3.6, 95% CI: 2.1-6.2; P.1: 2.6, 95% CI: 1.4-4.8) and B.1.1.7/SGTF and P.1 cases also for intensive care admission (B.1.1.7/SGTF: 2.3, 95% CI: 1.4-3.5; P.1: 2.2, 95% CI: 1.7-2.8).

Lyme borreliosis in Finland: a register-based linkage study.

BACKGROUND: In Finland, the routine surveillance of Lyme borreliosis (LB) is laboratory-based. In addition, we have well established national health care registers where countrywide data from patient visits in public health care units are collected. In our previous study based on these registers, we reported an increasing incidence of both microbiologically confirmed and clinically diagnosed LB cases in Finland during the past years. Here, we evaluated our register data, refined LB incidence estimates provided in our previous study, and evaluated treatment practices considering LB in the primary health care. METHODS: Three national health care registers were used. The Register for Primary Health Care Visits (Avohilmo) and the National Hospital Discharge Register (Hilmo) collect physician-recorded data from the outpatient and inpatient health care visits, respectively, whereas the National Infectious Diseases Register (NIDR) represents positive findings in LB diagnostics notified electronically by microbiological laboratories. We used a personal identification number in register-linkage to identify LB cases on an individual level in the study year 2014. In addition, antibiotic purchase data was retrieved from the Finnish Social Insurance Institution in order to evaluate the LB treatment practices in the primary health care in Finland. RESULTS: Avohilmo was found to be useful in monitoring clinically diagnosed LB (i.e. erythema migrans (EM) infections), whereas Hilmo did not add much value next to existing laboratory-based surveillance of disseminated LB. However, Hilmo gave valuable information about uncertainties related to physician-based surveillance of disseminated LB and the total annual number of EM infections in our country. Antibiotic purchases associated with the LB-related outpatient visits in the primary health care indicated a good compliance with the recommended treatment guidelines. CONCLUSIONS: Avohilmo and laboratory-based NIDR together are useful in monitoring LB incidence in Finland. A good compliance was observed with the recommended treatment guidelines of clinically diagnosed LB in the primary health care. In 2018, Avohilmo was introduced in the routine surveillance of LB in Finland next to laboratory-based surveillance of disseminated LB.

High-Dose Vitamin D Supplementation Does Not Prevent Allergic Sensitization of Infants.

OBJECTIVE: To investigate the effect of vitamin D supplementation dose on allergic sensitization and allergic diseases in infants, and to evaluate whether vitamin D status in pregnancy and at birth are associated with infant allergy outcomes. STUDY DESIGN: Altogether, 975 infants participated in a randomized, controlled trial of daily vitamin D supplementation of 10 µg (400 IU) or 30 µg (1200 IU) from the age of 2 weeks. At 12 months of age, food and aeroallergen IgE antibodies were measured, and the occurrence of allergic diseases and wheezing were evaluated. RESULTS: We found no differences between the vitamin D supplementation groups in food (OR, 0.98; 95% CI, 0.66-1.46) or aeroallergen sensitization at 12 months (OR, 0.76; 95% CI,0.34-1.71). Allergic diseases or wheezing did not differ between groups, except for milk allergy which occurred more often in infants administered 30 µg vitamin D compared with the 10 µg dose (OR, 2.23; 95% CI, 1.00-4.96). Infants with high cord blood 25-hydroxyvitamin D (≥100 nmol/L) had a higher risk of food allergen sensitization compared with those with lower 25(OH)D concentration (75-99.9 nmol/L; OR, 2.00; 95% CI, 1.19-3.39). CONCLUSIONS: High-dose vitamin D supplementation did not prevent allergic sensitization, allergic diseases, or wheezing during the first year of life. In contrast, we observed an increased risk of milk allergy in infants randomized to higher vitamin D supplementation, and an increased risk of allergic sensitization in infants with high cord blood vitamin D status, indicating a possible adverse effect of high concentrations of vitamin D.

The Potential Role of Matrix Metalloproteinases 8 and 9 and Myeloperoxidase in Predicting Outcomes of Bacterial Meningitis of Childhood.

BACKGROUND: Matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) contribute to the inflammatory cascade in the cerebrospinal fluid (CSF) during bacterial meningitis. We determined levels of MPO, MMP-8, MMP-9, and tissue inhibitor of metalloproteinase- (TIMP-) 1 in the CSF of children with bacterial meningitis and investigated how these inflammatory mediators relate to each other and to the disease outcomes. METHODS: Clinical data and the diagnostic CSF samples from 245 children (median age eight months) with bacterial meningitis were obtained from a clinical trial in Latin America in 1996-2003. MMP-9 levels in the CSF were assessed by zymography, while MMP-8, MPO, and TIMP-1 concentrations were determined with immunofluorometric and enzyme-linked immunosorbent assays. RESULTS: MPO correlated positively with MMP-8 (rho 0.496, P < 0.001) and MMP-9 (rho 0.153, P = 0.02) but negatively with TIMP-1 (rho -0.361, P < 0.001). MMP-8 emerged as the best predictor of disease outcomes: a CSF MMP-8 concentration above the median increased the odds of death 4.9-fold (95% confidence interval 1.8-12.9). CONCLUSIONS: CSF MMP-8 presented as an attractive prognostic marker in children with bacterial meningitis.

Season, dietary factors, and physical activity modify 25-hydroxyvitamin D concentration during pregnancy.

PURPOSE: The objectives of this cross-sectional study were to define maternal and umbilical cord blood (UCB) 25-hydroxyvitamin D (25(OH)D) to characterize maternal factors modifying 25(OH)D during pregnancy and predict UCB 25(OH)D in two subgroups with Declined [Δ25(OH)D <0 nmol/l] and Increased [Δ25(OH)D >0 nmol/l] 25(OH)D concentration. METHODS: A complete dataset was available from 584 women. 25(OH)D was determined at gestational weeks 6-13 and in UCB. Baseline characteristics were collected retrospectively using questionnaires. Δ25(OH)D was calculated as UCB 25(OH)D-early pregnancy 25(OH)D. Dietary patterns were generated with principal component analysis. Multivariate regression models were applied. RESULTS: Vitamin D deficiency was scarce, since only 1% had 25(OH)D concentration <50 nmol/l both in early pregnancy and in UCB. Shared positive predictors of UCB 25(OH)D in the subgroups of Declined and Increased, were early pregnancy 25(OH)D (P < 0.001) and supplemental vitamin D intake (P < 0.04). For the Increased subgroup summer season at delivery (P = 0.001) and "sandwich and dairy" dietary pattern characterized with frequent consumption of vitamin D fortified margarine and milk products (P = 0.009) were positive predictors of UCB 25(OH)D. Physical activity (P = 0.041) and maternal education (P = 0.004) were additional positive predictors in the Declined group CONCLUSIONS: Maternal and newborn vitamin D status was sufficient, thus public health policies in Finland have been successful. The key modifiable maternal determinants for 25(OH)D during pregnancy, and of the newborn, were supplemental vitamin D intake, frequent consumption of vitamin D fortified foods, and physical activity.