Vitamin B12

Vitamin B12 and Miscarriage

Vitamin B12 is 34% lower in women with recurrent miscarriage

Vitamin B12 was significantly decreased in patients with recurrent miscarriage compared to controls (mean concentrations 197 vs. 300 pg/mL). The lowest mean serum vitamin B12 (172 pg/mL) was observed in primary aborters (a woman who has no children, each pregnancy terminates in miscarriage). Homocysteine was elevated in women who miscarried in comparison to controls (8.3 vs. 7.1 micromol/L). Folate and methylmalonic acid (indicator of vitamin B12 deficiency) did not differ significantly between the study groups. A highly significant correlation between homocysteine and methylmalonic acid and vitamin B12 was observed only in patients but not in controls.

Miscarriage risk goes up 3.8 fold with every quartile of severity in vitamin B12 deficiency

In a conditional logistic regression analysis including age, gestational age, serum creatinine, methylmalonic acid, cystathionine, body mass index (BMI), cigarette smoking, alcohol ingestion and use of multivitamins the risk of miscarriage was significantly associated with methylmalonic acid (indicates vitamin B12 deficiency)(odds ratio =3.80 per quartile increase in methylmalonic acid), BMI (odds ratio =5.49 per quartile) and gestational age (odds ratio =0.10 per increase of interval in gestational age). CONCLUSIONS: Increased serum methylmalonic acid and BMI concentrations are associated with miscarriage in Brazilian women.

Vitamin B12 supplementation led to successful pregnancy in 80% of women with deficiency

Serum vitamin B12, folate and homocysteine levels were carried out in 110 consecutive women with unexplained early recurrent miscarriage or very early recurrent miscarriage and in 96 women with one or more children and no miscarriage history. RESULTS: Ten women (9%) were found to have low serum vitamin B12 levels versus one (1%) in the control group. A total of 50% of these had raised homocysteine. No difference was noticed between cases and controls for folate. Among women with low serum vitamin B12 level and early recurrent miscarriage, 87.5% of the miscarriages were very early recurrent miscarriage. Vitamin B12 supplementation led to four normal pregnancies in five women who became pregnant again. In a statistical analysis performed on five studies in which serum vitamin B12 was assayed in early recurrent miscarriage, including ours, a significant relationship was found between early recurrent miscarriage and Vitamin B12 deficiency. CONCLUSION: Vitamin B12 deficiency may be involved in early recurrent miscarriage. Vitamin B12 assay should be done in women with early recurrent miscarriage whether or not hematological abnormalities are present.

Vitamin B12 levels are 34% lower in women with recurrent miscarriage

In non-pregnant women with recurrent miscarriages, the average vitamin B12 concentration in blood serum was 178.3 pg/ml and it was statistically lower in comparison with the control group (268.6 pg/ml). No relation between the average concentration of vitamin B12 in blood serum and the average homocysteine in the nullipara (no children) group with recurrent miscarriage. CONCLUSIONS: Together with the increasing number of miscarriages, the average homocysteine concentrations grew and the average folic acid concentrations lowered.

Vitamin B12 deficiency leads to miscarriage via hypercoagulability and defective ovulation

The obstetric histories of 14 patients presenting with 15 episodes of vitamin B12 deficiency were analyzed. Infertility (two to eight years) had been present in four episodes, and recurrent miscarriage was a feature in 11. In six episodes, periods of recurrent miscarriage were followed by periods of infertility greater than one year. CONCLUSION: Hypercoagulability due to raised homocysteine levels may lead to fetal loss when vitamin B12 deficiency first develops. A more prolonged deficiency results in infertility by causing changes in ovulation or development of the ovum or changes leading to defective implantation.

For a concise list of qualities found to affect one's risk of miscarriage, see: Causes of Miscarriage

Other topics covered under Vitamin B12:

Vitamin B12 and Birth Defects

Other topics covered under Vitamins:

Biotin, Calcium, Choline, Chromium, Folic Acid, Magnesium, Multivitamins, Phosphorus, Selenium, Vitamin A, Vitamin B12, Vitamin B6, Vitamin C, Vitamin D, Vitamin E, Vitamin K, Zinc