Dietary pattern and nutritional assessment in a cohort of mothers identified by neonatal screening for cobalamin deficiency in offspring: an Italian single center experience

Martina Tosi^1,2Veronica Maria Tagi^1,3Alice Colombo¹Alessandra Cecchini¹Marianna Zobele¹Chiara Montanari^1,3Simona FERRARO¹Alessandra Bosetti¹Eleonora Bonaventura^4,5Fabio Bruschi^3,4Diego De Zan¹Giulia Fiore^1,3Cristina Cereda^1,6Gianvincenzo Zuccotti^1,3*Elvira Verduci^2,7

• ¹Department of Pediatrics, Vittore Buzzi Children's' Hospital, Milan, Lombardy, Italy
• ²Department of Health Sciences, University of Milan, Milan, Lombardy, Italy
• ³Department of Biomedical and Clinical Science, University of Milan, Milan, Lombardy, Italy
• ⁴Center for Diagnosis and Treatment of Leukodystrophies, Vittore Buzzi Children's Hospital, Milan, Lombardy, Italy
• ⁵Unit of Pediatric Neurology, Vittore Buzzi Children’s Hospital, Milan, Lombardy, Italy
• ⁶Center of Functional Genomics and Rare Diseases, Buzzi Children’s Hospital, Milan, Lombardy, Italy
• ⁷Metabolic Diseases Unit, Department of Pediatrics, Vittore Buzzi Children’s Hospital, Milan, Lombardy, Italy

During pregnancy, nutrient requirements increase while deficiencies can significantly affect pregnancy outcomes. Deficiencies may result from inadequate dietary intake, impaired absorption, or restrictive diets. This study aimed to retrospectively assess the nutritional status and dietary intakes in a cohort of mothers whose newborns were identified with vitamin B12 deficiency of maternal origin through Newborn Screening. Between 2021 and 2024, 107 newborn-mother dyads with altered biomarkers of cobalamin metabolism were identified and referred to the Metabolic Disease Unit for further evaluation and treatment. Mothers underwent biochemical assessments and nutritional interviews regarding pregnancy diet history, and dietary intakes were quantified using a dedicated software (MetadietaVR). Most of the cohort (47%) was from Asia, with an average age of 32.5 years. Plasma vitamin B12 levels averaged 240 pg/ml. Mothers who reported taking vitamin B12 supplements had higher plasma levels compared to those who did not supplement with B12 (255.5±113 vs 231.2±104 pg/ml). Dietary habits during pregnancy revealed that 71% of mothers were omnivorous (O), 16% followed a lacto-vegetarian (LV) diet, 12% a lacto-ovo-vegetarian (LOV) diet, and 1% a vegan (V) diet. Most mothers (90%) were taking supplements during pregnancy, with 70.7% taking folic acid, 68.7% iron and 15% vitamin B12. Among women who achieved adequate vitamin B12 intake through both diet and supplementation, 95% were omnivores while 5% followed a LOV diet. This study emphasizes the importance of addressing maternal nutritional needs from the pre-conception period, as dietary patterns may not adequately reflect micronutrient intake. Even omnivorous diets, if unbalanced, can result in insufficient nutrient intake, underlying the necessity of targeted nutritional support during pregnancy.