Research indicates that at least one-third of women develop marginal vitamin B7 (biotin) deficiency during the course of pregnancy (6, 8, 9, 11). However, it is still unknown whether this decline in biotin nutritional status might elevate the risk of congenital anomalies (45). Although the level of biotin depletion is not severe enough to cause diagnostic signs or symptoms, such observations are sources of concern because biotin deficiency without clinical signs or symptoms (‘subclinical’) has been shown to cause birth defects such as cleft palate and limb hypoplasia in several animal species (9, 10).
The potential risk for abnormal development of the embryo or fetus (‘teratogenesis’) from biotin deficiency (impaired carboxylase activity) (6, 9, 59, 61) makes it prudent to ensure adequate biotin intake throughout pregnancy. Since pregnant women are advised to consume supplemental vitamin B9 (folic acid) prior to and during pregnancy to prevent neural tube defects, it would be easy to consume supplemental biotin (at least 30 mcg/day) in the form of a multivitamin that also contains at least 400 mcg folic acid. Toxicity at this level of biotin intake has never been reported (see Safety).
Authored by Dr Peter Engel in 2010, reviewed and revised by Ines Warnke on 28.06.2017