Schizophrenia affects approximately 24 million people globally and is thought to stem from genetic, environmental, and neurodevelopmental factors. However, one potential factor that remains unexplored is maternal nutritional deficiencies during pregnancy, particularly vitamin B12, which is crucial to neurodevelopment.
A recent study aimed to investigate this research gap and determine whether lower B12 levels during early pregnancy are associated with an increased risk of schizophrenia in offspring. Here’s an in-depth look at the study.
The Design of the Study
This nationwide, population-based nested case-control study utilized data from the Finnish Prenatal Study of Schizophrenia (FIPS-S). The study cohort included all singleton live births in Finland from 1987 to 1997 and assessed follow-up data on schizophrenia diagnoses until 2017.
A total of 1,145 schizophrenia cases were identified in this group, and each were matched with one control by sex, birth date, and location. To compare maternal vitamin B12 levels in these groups, serum samples were collected with chemiluminescence microparticle immunoassay during the first and early second trimesters. Conditional logistic regression models were then used to assess associations, with vitamin B12 analyzed as both a continuous and categorical variable.
The study also adjusted for confounding factors, including parental psychopathology, maternal socioeconomic status, gestational age, and region of birth.
The Results of the Study
Looking at the results, the study found that:
- Vitamin B12 levels were not associated with schizophrenia.
- There was no significant association between maternal vitamin B12 levels and offspring schizophrenia in either unadjusted (OR: 1.04, 95% CI: 0.88–1.24) or adjusted analyses (aOR: 1.14, 95% CI: 0.95–1.37).
- There was no association between the lowest versus highest quintiles and deciles of B12 levels.
- No significant difference in schizophrenia risk was observed when comparing the lowest and highest quintiles and deciles of maternal B12 levels (adjusted OR for the lowest quintile: 0.89, 95% CI: 0.68–1.17).
- Sex was not a factor in effect modification.
- The association between maternal B12 levels and schizophrenia did not differ significantly by offspring sex.
The Implications of the Study
Given these results, maternal vitamin B12 levels during early pregnancy were not associated with an increased risk of schizophrenia in offspring. Looking ahead, these findings suggest that further research should explore the combined roles of genetic and environmental factors and evaluate the effects of other nutritional deficiencies during pregnancy.
Reference:
Sourander A, Silwal S, Surcel HM, et al. Maternal vitamin B12 during pregnancy and schizophrenia in offspring. Psychiatry Res. 2025;344:116284. doi:10.1016/j.psychres.2024.116284