Calcium in pregnancy is an essential mineral, whose sufficient intake should be ensured because it helps to develop strong bones and muscles in the baby. Along with iron, calcium forms an indispensable mineral required during pregnancy.

According to the CDC and the U.S. Department of Agriculture (USDA): 7 out of 10 Americans are deficient in calcium.

If your calcium intake is low, calcium is released from the bones of the mother toward the end of the pregnancy. This may lead to low bone mineral density (BMD) in the mother, risk of delayed bone growth in the newborn, and low BMD and weakened teeth in the child later on in life.

You require high calcium during the pregnancy and lactation periods. The bones of a newborn baby contain about 20-30 g of calcium.

Most of the fetal bony growth takes place from mid-pregnancy onwards, with maximal calcium requirement for skeletal growth occurring during the third trimester.

The total calcium requirement of the fetus increases from about 50 mg/day at 20 weeks gestation to 330 mg/day at 35 weeks.

During the third trimester of pregnancy, the average calcium requirement rate is down to 200 mg/day for proper bone growth.

The potential complications of calcium deficiency due to its poor intake during pregnancy may adversely affect bone metabolism, may cause hypertensive disorders that can lead to preeclampsia, and also retard fetal growth.

It is important to note here that your body needs vitamin D to absorb calcium, so be sure to get enough of this vitamin from sunlight exposure and /or supplements. Additionally, add vitamin D foods to your pregnancy diet.

Calcium dosage in pregnancy

Women need the same amount of calcium at all times: while pregnant, while breastfeeding, and also when neither of these is present. However, the required amount of calcium women need does vary by age:

The recommended daily allowance (RDA) of calcium

  • for a pregnant and lactating woman above 19 years of age is about 1200 mg of calcium per day
  • while it is 1300 mg for pregnant women below the age of 18 years.

The American College of Obstetricians and Gynecologists (ACOG) recommends that pregnant and breastfeeding moms aged 19 years and above consume 1,000mg of calcium each day.

Prenatal calcium supplements are, therefore, quite often recommended during pregnancy.

Benefits of calcium during pregnancy

The importance of calcium requirement can be gauged from the following benefits it imparts to the baby.

  • Calcium makes strong bones and teeth
  • Prevents the formation of blood clots
  • Helps in the function of nerves and
  • Better development of muscles
  • Calcium reduces the risk of hypertension and preeclampsia during pregnancy.
  • When there is inadequate intake of calcium by the pregnant mother, calcium is drawn from her bones to fulfill the requirement of the developing fetus. This could cause serious health conditions for the mother such as osteoporosis and lower bone density in the offspring

Most of the skeletal growth of the fetus starts from mid-pregnancy with maximum accumulation taking place in the last trimester. This is why the expecting mother is required to cater to additional calcium requirements through a calcium-rich diet.

Calcium supplements during pregnancy

You may require calcium supplements if you are not getting enough of it from your diet. A well-balanced pregnancy diet though can give you your adequate calcium need

Besides giving your calcium requirement, calcium supplementation is also associated with improved cholesterol metabolism, lowering of low-density lipoprotein (LDL), and increase in high-density lipoprotein (HDL).

Calcium supplements may come either as calcium carbonate or calcium citrate. However, calcium citrate is better absorbed in the body.

Calcium carbonate provides more calcium, but it should be taken with food. This is because acid produced in the stomach while eating helps in the better absorption of calcium carbonate.

Calcium citrate is more easily absorbed by the body as it does not require stomach acid for absorption. It can, therefore, be taken on an empty stomach, which facilitates better absorption. It is also the calcium of choice for those suffering from heartburn.

Your prenatal supplement probably also contains calcium in doses of 150 to 200 mg. Your body will absorb only 500 mg at a time so plan your intake of calcium supplements accordingly or as advised by your doctor.

You should take oral calcium tablets twice a day (total 1g calcium/day) starting from 14 weeks of pregnancy up to six months post-delivery. Ideally, you should take one calcium tablet with the morning meal and the second tablet with dinner.

Calcium also interferes with the absorption of iron in the intestines, therefore take your calcium supplements at a separate time of the day from your iron supplements.

Make sure that your calcium supplement does not contain lead by reading from the label. Lead can cause harm to your baby. Such supplements, which you should avoid include those containing bone meal, dolomite, oyster shell, or coral.

Secondly, don’t go overboard with calcium supplements. Make sure your calcium intake from food and supplements doesn’t exceed 2500 mg (or 3000 mg if you’re younger than 18).

Too much calcium can cause side effects such as constipation, increased risk of kidney stones, and improper absorption of iron and zinc from foods.

Best calcium-rich foods

  • Milk
  • Yogurt
  • Cheddar cheese
  • Green leafy vegetables and broccoli.
  • Foods fortified with calcium such as soy milk, juices, bread, and cereals.
  • Sesame seeds.
  • Nuts such as almonds and walnuts.
  • Fish such as tinned sardines.
  • Even after the birth of your baby, you should continue to take proper calcium intake. This will keep your bones strong and prevent osteoporosis (bone loss) later in life.

Complications of too much and too little calcium during pregnancy

Complications can arise from calcium deficiency or too much calcium.

Too Little Calcium

Calcium deficiency due to poor intake, per se, may not cause pregnancy complications

A calcium deficiency is more likely to cause complications if the deficiency is due to a health condition such as kidney disease, surgery, or certain medications.

Calcium deficiency during pregnancy can lead to:

  • High blood pressure during pregnancy
  • Premature birth
  • Baby with low birth weight
  • Numbness and tingling in the fingers
  • Slow growing baby
  • Heart problems
  • Muscle and leg cramps
  • Higher risk of bone fractures

Too Much Calcium

It is rare to get too much calcium from the foods that you eat. You are most likely to build up an excessive amount of calcium in your body from your supplements.

It is, therefore, always best to talk to your doctor about any supplements that you are taking so that you do not consume too much calcium.

If you are 19 or older, please ensure that you do not take more than 2,500mg of calcium each day, and if you are 18 or younger, do not consume more than 3,000 mg daily.

Complications of consuming too much calcium can cause:

  • Constipation
  • Kidney stones
  • Poor absorption of iron and zinc
  • Irregular heartbeat
  • Baby with low calcium