ABSTRACT
OBJECTIVE: Vitamin B12 deficiency has been linked to neurocognitive symptoms. Vitamin B12 deficiency in pregnancy may be associated with antenatal or postpartum depression along with other neurocognitive symptoms including restless leg syndrome. The objective of this study was to systematically review the literature regarding vitamin B12 deficiency and insufficiency in pregnancy and its effects on maternal neurocognitive symptoms. DATA SOURCES: MEDLINE, Embase, and SCOPUS were searched from inception to October, 2020. STUDY SELECTION: Observational studies and randomized controlled trials of singleton pregnancies involving vitamin B12 deficiency and reporting maternal neurocognitive outcomes were identified. DATA EXTRACTION AND SYNTHESIS: Data were synthesized and are presented narratively. CONCLUSIONS: The 5 studies included in the analysis did not demonstrate a statistically significant link between vitamin B12 deficiency or insufficiency and either restless leg syndrome or depression in pregnancy. To date, evidence is lacking that would support a causal link between suboptimal vitamin B12 serum levels and maternal restless leg syndrome or depression.
