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Calcium phosphate, tribasic Pregnancy and Breastfeeding Warnings

Brand names: Posture

Medically reviewed by Drugs.com. Last updated on Jun 26, 2023.

Calcium phosphate, tribasic Pregnancy Warnings

Calcium phosphate has not been formally assigned to a pregnancy category by the FDA. It is considered a nutritional supplement, and is indicated for human pregnancy. Neither animal reproductive studies nor controlled data from human pregnancy are available.

Calcium is transported across the human placenta. The human fetus is entirely dependent on its mother for its supply of nutrients--including calcium--and oxygen and for the removal of waste products. Fetal accumulation of calcium occurs mainly during the third trimester. By the end of normal human pregnancy the fetus acquires approximately 28 grams of calcium and 16 grams of phosphorus.

The additional calcium required during pregnancy is needed mainly for the fetal skeleton. The recommended daily calcium supplementation for a pregnant woman averages 1,200 mg (compared with 400 mg/day in the nonpregnant adult), with an additional 250 to 300 mg/day recommended during the last trimester. One quart of milk contains approximately 1,200 mg of calcium; women who do not consume milk or milk products generally require calcium supplementation.

There are limited data regarding the treatment of pregnant women with hyperparathyroidism who received oral phosphate therapy because they were not considered surgical candidates. The possible side effects of maternal hyperparathyroidism on the fetus or newborn include prematurity and hypocalcemic tetany. From the limited data available, no adverse effects from maternal oral phosphate therapy were noted in their offspring.

See references

Calcium phosphate, tribasic Breastfeeding Warnings

The calcium content of human milk averages 30 mg/dl. The recommended daily allowance (RDA) for calcium in the lactating woman is 1,200 mg (compared with 400 mg/day in the nonlactating adult). One quart of milk contains approximately 1,200 mg of calcium; women who do not consume milk or milk products generally require calcium supplementation.

There are no data on the excretion of calcium phosphate into human milk. Calcium is a normal nutritional component of human milk.

See references

References for pregnancy information

  1. Crawford JS. Maternal and cord blood at delivery. IV. Glucose, sodium, potassium, calcium and chloride. Biol Neonat. 1965;8:222-37.
  2. Lopez-Jaramillo P, Narvaez M, Weigel RM, Yepez R. Calcium supplementation reduces the risk of pregnancy-induced hypertension in an Andes population. Br J Obstet Gynaecol. 1989;96:648-55.
  3. Danforth D, Scott J, DiSaia P, Hammond C, Spellacy W, Eds. Obstetrics and Gynecology, Fifth Edition. JB Lippincott Company, Philadelphia. 1986;1:181-93.
  4. Ammann P, Irion O, Gast J, Bonjour JP, Beguin F, Rizzoli R. Alterations of calcium and phosphate metabolism in primary hyperparathyroidism during pregnancy. Acta Obstet Gynecol Scand. 1993;72:488-92.
  5. Husain SM, Mughal MZ. Mineral transport across the placenta. Arch Dis Child. 1992;67:874-8.
  6. Montoro MN, Collea JV, Mestman JH. Management of hyperparathyroidism in pregnancy with oral phosphate therapy. Obstet Gynecol. 1980;55:431-4.
  7. Product Information. Posture (calcium phosphate, tribasic). Whitehall-Robbins. PROD.

References for breastfeeding information

  1. Danforth D, Scott J, DiSaia P, Hammond C, Spellacy W, Eds. Obstetrics and Gynecology, Fifth Edition. JB Lippincott Company, Philadelphia. 1986;1:181-93.
  2. Fenuku RI, Earl-Quarcoo SN. Serum calcium, magnesium and inorganic phosphate during lactation. Trop Geogr Med. 1978;30:495-8.
  3. Product Information. Posture (calcium phosphate, tribasic). Whitehall-Robbins. PROD.

Further information

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