Calcium is one of the most important minerals in pregnancy. Your baby needs it to build bones and teeth, and to help the heart, nerves and muscles develop. By the end of pregnancy, a baby has taken on about 30 grams of calcium — nearly all of it in the last three months, when the skeleton is growing fastest.

If your diet does not supply enough calcium, your body draws on the calcium stored in your own bones to meet your baby’s needs. Making sure you get enough protects both of you.

We recommend calcium for every pregnant woman

At Sugabi Clinic we advise routine calcium supplementation for all pregnant women. Most diets in Sri Lanka do not reach the calcium levels needed in pregnancy, and good calcium intake lowers the risk of high blood pressure and pre-eclampsia — one of the more serious complications of pregnancy.1 Pooled trial evidence suggests the benefit is largest in women whose everyday diet is low in calcium.2

How much calcium you should take

  • Most women: a standard dose of 500 mg of calcium a day.
  • Women found to have low calcium: a higher dose, stepped up as needed to a maximum of 1,500 mg a day.

Your doctor will tell you which dose is right for you and when to start. Calcium is usually given as a combined calcium and vitamin D tablet, because vitamin D helps your body absorb calcium properly. Most of these tablets contain about 400 IU of vitamin D.3

Take your tablets with meals if you can, and keep to the dose you are given — more is not better, and very high intakes can cause constipation or, rarely, kidney stones.

One timing tip: keep calcium and iron apart

Calcium and iron compete for absorption. If you take both, separate them by at least two hours — for example, calcium with breakfast and iron later in the day.

Calcium-rich foods to include

Supplements work best alongside a good diet. Sri Lankan foods naturally rich in calcium include:

  • Milk, curd and yoghurt
  • Small fish eaten with the bones (such as sprats)
  • Green leafy vegetables (gotukola, kangkung, mukunuwenna)
  • Sesame seeds (thala) and other seeds and nuts
  • Dhal and other pulses

The bottom line

Calcium matters for your bones and your baby’s development, and it lowers the risk of high blood pressure and pre-eclampsia. At Sugabi Clinic we recommend a calcium supplement for every pregnant woman — a standard 500 mg a day for most, and a higher dose up to 1,500 mg a day if you are found to be low. For more on eating well in pregnancy, see our guide to nutrition in pregnancy.

Always follow the dose your own doctor gives you, as it is tailored to your needs.

References

  1. World Health Organization. WHO recommendation: calcium supplementation during pregnancy for the prevention of pre-eclampsia and its complications. Geneva: WHO; 2018. Available from: https://www.who.int/publications/i/item/9789241550451
  2. Hofmeyr GJ, Lawrie TA, Atallah ÁN, Torloni MR. Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems. Cochrane Database Syst Rev. 2018;10:CD001059. Available from: https://www.ncbi.nlm.nih.gov/books/NBK535812/
  3. National Health Service. Vitamins, supplements and nutrition in pregnancy [Internet]. NHS; [cited 2026 Jul 22]. Available from: https://www.nhs.uk/pregnancy/keeping-well/pregnancy-vitamins-and-supplements/
  4. National Health Service. Calcium — vitamins and minerals [Internet]. NHS; [cited 2026 Jul 22]. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/calcium/