The Importance of Calcium for Pregnant Women
During pregnancy, women experience a significant loss of calcium, which is crucial for both the mother and the developing fetus. It is essential for pregnant women to supplement their calcium intake as the fetus derives all its calcium from the mother’s body. This means that a substantial amount of the calcium present in the pregnant woman's system is transferred to the baby. If a pregnant woman does not receive adequate calcium, it can severely affect both her health and the development of the fetus.
In cases of mild calcium deficiency, the body compensates by drawing calcium from the mother’s bones to maintain normal blood calcium levels. However, severe deficiency can lead to symptoms such as leg cramps and even osteomalacia. Moreover, a lack of calcium can adversely impact the fetus's growth and development, leading to conditions such as cranial softening, wide sutures, and abnormal closure of the fontanelle.
Calcium Needs During Pregnancy
A mature fetus contains approximately 30 grams of calcium. Throughout the various stages of pregnancy, the daily calcium accumulation in the fetus is about 7 mg in early pregnancy, 110 mg in mid-pregnancy, and 350 mg in late pregnancy. Along with the maternal metabolic balance for calcium, which requires an additional 300 mg per day, the recommended daily intake of calcium is 1000 mg for pregnant women in their second trimester and 1200 mg in their third trimester, as outlined in the 2000 Dietary Nutrient Reference Intake for Chinese Residents.
However, studies have shown that the actual daily dietary calcium intake for many pregnant women in China ranges from 500 mg to 800 mg, indicating a discrepancy with the recommended intake. It is important to note that individual dietary habits can vary widely, leading to different levels of calcium consumption. Therefore, calcium supplementation should be tailored to the individual needs of each pregnant woman.
How Should Pregnant Women Supplement Calcium?
Pregnant women often experience leg cramps around the sixth month and might instinctively attribute this to a lack of calcium. However, it is essential to recognize that leg cramps are not solely caused by calcium deficiency. After six months of pregnancy, the growing uterus and placenta can exert pressure on the pelvic blood vessels and nerves, particularly when the woman lies on her back. This pressure can impede blood flow to the legs, which can be a contributing factor to cramps. Traditional Chinese medicine suggests that “where there is no flow, there is pain,” highlighting one reason for these cramps.
One concerning case involved a woman who underwent a cesarean section to deliver a stillborn child. The placenta was found to be covered in hard, cement-like calcifications due to the woman taking three calcium tablets daily since her sixth month of pregnancy.
After the fifth month of pregnancy, the daily requirement for calcium increases, but this can typically be met through a balanced diet without the need for excessive supplementation. Foods rich in calcium include pork, pork bone soup, pork stomach, lamb liver, chicken, fish, eggs, milk, goat milk, dairy products, grains, bread, cakes, fresh vegetables, and fruits. By focusing on a nutrient-rich diet, pregnant women can effectively meet their calcium needs while supporting their overall health and that of their developing child.