Maternal Peri- and Postconceptional Folic Acid Supplementation and Ankyloglossia in Newborns

Background: Ankyloglossia (“tongue-tie”) is a congenital condition characterized by restricted tongue mobility due to a shortened or thickened lingual frenulum. Diagnoses of ankyloglossia in newborns have increased globally. While improved awareness and breastfeeding promotion partially explain this trend, maternal folic acid supplementation may also influence midline tissue development. Objective: To investigate the association between maternal peri- and postconceptional folic acid supplementation and the occurrence of ankyloglossia in newborns. Methods: A retrospective case-control study was conducted at the Seeklinik Zurich, a specialized center for oral and maxillofacial surgery, from February 2019 to March 2025. Maternal folic acid intake was documented via standardized questionnaires. The study group included 247 mother-infant pairs referred for suspected ankyloglossia, of which 216 infants had confirmed tongue-tie. The control group comprised 154 mother-infant pairs with no reported maternal folic acid intake; 10 infants with tongue-tie were excluded, leaving 144 for comparison. Statistical analyses included odds ratios with Haldane’s correction, chi-square tests, and t-tests. Results: Maternal folic acid supplementation was reported by 87.45% of mothers in the study group versus 0% in the control group (p < 0.001). The approximate odds ratio using Haldane correction was 62.4 (95% CI 24–∞). Cases showed a male predominance (72.7%) and younger maternal age (27.2 ± 6.5 years vs. 30.1 ± 6.4; p < 0.005). Conclusion: Maternal folic acid supplementation is strongly associated with ankyloglossia in this cohort. While causality cannot be established, the findings suggest a potential influence of folate on midline tissue development. Prospective studies are warranted to confirm these observations and explore underlying mechanisms.