Zinc Supplementation During Pregnancy
Zinc is considered safe during pregnancy and can be continued throughout pregnancy without dosage adjustments. 1
Safety and Efficacy of Zinc in Pregnancy
Zinc supplementation during pregnancy has been well-studied, particularly in the context of Wilson's disease (WD) treatment. The European Association for the Study of the Liver (EASL) clinical practice guidelines clearly state that zinc is considered safe in pregnancy and can be continued throughout pregnancy without any dose reduction 1. This contrasts with chelating agents like D-penicillamine and trientine, which require dose reductions during pregnancy.
The FDA labeling for zinc sulfate also supports its safety during pregnancy, noting that "administration of the approved recommended dose of Zinc Sulfate in parenteral nutrition is not expected to cause major birth defects, miscarriage, or adverse maternal or fetal outcomes" 2.
Zinc in Wilson's Disease During Pregnancy
For pregnant women with Wilson's disease:
- Zinc can be continued at the same dosage throughout pregnancy 1
- Treatment must be maintained throughout pregnancy to prevent hepatic deterioration 1
- Interruption of treatment during pregnancy has resulted in acute liver failure 1
- Experience indicates that zinc salts have been associated with satisfactory outcomes for both mother and fetus 1
A systematic review of 822 pregnancies in 449 women with Wilson's disease showed that anti-copper treatment (including zinc) was associated with positive maternal and fetal outcomes 1. Additionally, a retrospective study of 282 pregnancies in women with Wilson's disease found that spontaneous abortion occurred less frequently in women maintained on therapy (including zinc) compared to those who stopped treatment 1.
Zinc Requirements During Pregnancy
The recommended daily intake of zinc during pregnancy is 15mg, which is often not met by average dietary intake during pregnancy 3. Zinc supports immune function and energy metabolism, making it an important nutrient during pregnancy.
Potential Benefits of Zinc Supplementation
Some research suggests that zinc supplementation during pregnancy may provide benefits:
- A meta-analysis indicates a 14% reduction in premature delivery among zinc-supplemented women 4
- May have a positive effect on birthweight in underweight or zinc-deficient women 4
- Preliminary evidence suggests beneficial effects on neonatal immune status and infant morbidity from infectious diseases 5
Breastfeeding Considerations
A prospective study of 18 women with Wilson's disease treated with zinc reported normal concentrations of copper and zinc in breastmilk with no differences compared to controls 1. Therefore, women receiving zinc treatment should not be discouraged from breastfeeding.
Cautions and Monitoring
While zinc is generally safe during pregnancy, there are some considerations:
- Long-term high-dose zinc supplementation may result in decreased copper absorption and copper deficiency 2
- Monitoring of zinc, copper, and ceruloplasmin levels may be appropriate for women on long-term zinc therapy 2
- Hypersensitivity reactions to zinc-containing products have been reported, though rare 2
Conclusion
Based on the most recent and highest quality evidence from clinical practice guidelines, zinc supplementation is safe during pregnancy and can be continued throughout pregnancy without dosage adjustments. For women with Wilson's disease, maintaining zinc therapy during pregnancy is essential for preventing disease exacerbation and ensuring positive maternal and fetal outcomes.