Calcium during pregnancy
Lexine Hebets, MD, FACOG, AOA Arizona OB-GYN Affiliates, is on staff in the Department of Obstetrics and Gynecology at Banner Good Samaritan Medical Center.
Question: I don't eat or drink a lot of dairy - how important is calcium during my pregnancy?
Answer: Getting enough calcium is an important part of everyone’s diet, and that is especially true during pregnancy. In fact, the need for calcium is even greater during gestation, particularly in the second and third trimesters.
The fetal skeleton requires calcium to develop strong bones. If a woman’s calcium intake is not sufficient, her fetus will use calcium from her own calcium stores, primarily her bones. However, bone loss during pregnancy is usually minimal.
Fortunately, the body’s ability to absorb calcium is increased during pregnancy due to the placental production of vitamin D, which is necessary for calcium absorption. The recommended daily amount (RDA) of vitamin D is 600 international units (IU). That figure increases to 800IU during pregnancy.
A woman’s calcium RDA varies with age. Teens require 1,300mg per day and can safely go up to 3,000mg daily. Women between 19 and 50 require 1,000mg per day. The higher safe limit during pregnancy is 2,500mg daily.
Carrying twins increases a woman’s calcium needs. During the first trimester with twins, the calcium requirement is 1,500mg per day. That increase to 2,500mg daily during the second and third trimesters.
Eight ounces of skim milk provides 290mg of calcium, eight ounces of yogurt provides 450mg, and one ounce of cheddar cheese provides 200mg.
A fetus receives calcium derived from the mother’s diet as well as supplements. Calcium is available in multiple supplement forms, including carbonate, citrate and gluconate. Most prenatal vitamins provide adequate amounts of vitamin D to ensure proper calcium absorption.