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Calcitonin Pregnancy and Breastfeeding Warnings

Calcitonin is also known as: Calcimar, Fortical, Miacalcin, Miacalcin Nasal

Medically reviewed by Last updated on Dec 18, 2018.

Calcitonin Pregnancy Warnings

Calcitonin has been assigned to pregnancy category C by the FDA. Animal studies using synthetic salmon calcitonin have shown a decrease in fetal birth weights when rabbits were given doses 14 to 56 times the recommended human dose. There are no controlled data in human pregnancy. Calcitonin is only recommended for use during pregnancy when benefit outweighs risk.

Animal studies suggest that calcitonin does not cross the placental barrier.

Maternal calcitonin levels increase during pregnancy. These levels are not correlated with serum calcium or phosphate except when inversely proportional to the serum phosphate during the first trimester. The significance of this rise to the fetus is unknown.

See references

Calcitonin Breastfeeding Warnings

Calcitonin is found as a normal constituent of human milk, both in normal and thyroidectomized women. Levels are about 40 times that found in serum.

Calcitonin is a peptide and is likely digested in the gastrointestinal tract of the infant. However, studies of drug activity after ingestion have not been done in nursing infants.

Exogenous calcitonin has been shown to inhibit lactation in animal studies.

There are no data on the excretion of calcitonin into human milk. The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

See references

References for pregnancy information

  1. Kalu DN, Foster GV "Calcitonin. Its physiologic roles." N Y State J Med 76 (1976): 230-3
  2. "Product Information. Calcimar (calcitonin)." Rhone-Poulenc Rorer, Collegeville, PA.
  3. Samaan NA, Anderson GD, Adam-Mayne ME "Immunoreactive calcitonin in the mother, neonate, child and adult." Am J Obstet Gynecol 121 (1975): 622-5
  4. Silva OL, Titus-Dillon P, Becker KL, Snider RH, Moore CF "Increased serum calcitonin in pregnancy." J Natl Med Assoc 73 (1981): 649-52
  5. Woloszczuk W, Kovarik J, Pavelka P "Calcitonin in pregnant women and in cord blood." Gynecol Obstet Invest 12 (1981): 272-6

References for breastfeeding information

  1. Greer FR, Lane J, Ho M "Elevated serum parathyroid hormone, calcitonin, and 1,25- dihydroxyvitamin D in lactating women nursing twins." Am J Clin Nutr 40 (1984): 562-8
  2. "Product Information. Calcimar (calcitonin)." Rhone-Poulenc Rorer, Collegeville, PA.
  3. Bucht E, Sjoberg HE "Evidence for precursors of calcitonin/PDN 21 in human milk." Regul Pept 19 (1987): 65-71
  4. Bucht E, Telenius-Berg M, Lundell G, Sjoberg HE "Immunoextracted calcitonin in milk and plasma from totally thyroidectomized women. Evidence of monomeric calcitonin in plasma during pregnancy and lactation." Acta Endocrinol (Copenh) 113 (1986): 529-35
  5. Bucht E, Arver S, Sjoberg HE, Low H "Heterogeneity of immunoreactive calcitonin in human milk." Acta Endocrinol (Copenh) 103 (1983): 572-6

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.