In “Vitamin D supplementation: navigating the debate” (BPJ
36, June 2011) you mention the Australian and New Zealand College of Obstetricians guidelines recommending vitamin D
supplementation for pregnant women considered to be at risk of deficiency. This advice is alluded to again in “Routine
laboratory testing during pregnancy” (Best Tests, July 2011).
I have recently seen a patient who was prescribed vitamin D in pregnancy but the patient leaflet she was given with
the prescription advised against the taking of cholecalciferol in pregnancy and the datasheet (dated 26/8/10) includes
the following advice:
“Use in Pregnancy: Problems in humans have not been documented with intake of normal
daily requirements. Maternal hypercalcaemia during pregnancy in humans may be associated with increased sensitivity
to effects of vitamin D, suppression of parathyroid function, or a syndrome of peculiar (elfin) facies, mental retardation
and congenital aortic stenosis in infants.
Overdosage of vitamin D has been associated with foetal abnormalities in animals. Animal studies
have shown calcitriol to be teratogenic when given in doses 4 and 15 times the dose recommended for human use. Excessive
doses of dihydrotachysterol are also teratogenic in animals. Animal studies have also shown calcifediol to be teratogenic
when given in doses of 6 to 12 times the human dose.
FDA Pregnancy Category C”
I would be grateful to know how we should be advising patients regarding the safety of vitamin D supplements in pregnancy
given the contradictory nature of the advice given in the Guidelines and the medicine information sheets. Also is the
FDA category C equivalent to the Australian category C?
Dr Dr Phil White, General Practitioner
The Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) recommends that women with known
vitamin D deficiency or who are at risk of deficiency (e.g. dark skinned, women who are veiled), should receive vitamin
D supplementation during pregnancy.1,2 The recommended treatment is with cholecalciferol. Calcitriol is not
routinely used during pregnancy and would only be considered in the case of hypocalcaemia or chronic renal failure.2 Calcium
supplementation is recommended in women whose dietary intake is inadequate.
Cholecalciferol is considered safe to use during pregnancy when used at therapeutic levels.3 The United
States Food and Drug Administration (FDA) pregnancy Category C is different from the Australian Drug Evaluation Committee
pregnancy Category C. The FDA Category C is: “Animal reproduction studies have shown an adverse effect on the
foetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the
drug in pregnant women despite potential risks.”
There appears to be a lack of consensus as to the exact dose and regimen of cholecalciferol recommended for pregnant
women. A normal regimen for an adult with vitamin D deficiency would be a loading dose of 2 x 1.25 mg cholecalciferol
followed by 1 x 1.25 mg cholecalciferol per month. Ideally women, at risk of vitamin D deficiency, should be treated
pre-conceptually with this dose.
National Health and Medical Research Council guidelines for nutrient reference values for Australia and New Zealand
recommend that a daily amount of 80 µg (3200 I.U) cholecalciferol should not be exceeded during pregnancy. The
guidelines recommend a supplement of 10 µg (400 I.U) cholecalciferol per day for pregnant women at risk of vitamin
D deficiency.4 Guidance from the Royal College of Obstetricians and Gynaecologists (United Kingdom) and the
National Institute for Health and Clinical Excellence (United Kingdom), is in accord with this recommendation.5,6
However, a recent study found that higher doses of cholecalciferol (100 µg / 4000 I.U) given daily are safe
during pregnancy (i.e. no evidence of hypercalcaemia and hypercalcuria), and resulted in higher vitamin D status in
women and neonates than the currently recommended 10 µg per day.7
Some practitioners are recommending that the usual adult dose of cholecalciferol (a loading dose of 2 x 1.25 mg cholecalciferol
followed by 1 x 1.25 mg cholecalciferol per month) is used for pregnant women with vitamin D deficiency. However, there
is no evidence of the safety of this dose in pregnancy.
Although guidelines may change in the future, at this time it would be reasonable to recommend that pregnant women
at risk of vitamin D deficiency obtain their vitamin D requirements through a daily pre-natal multivitamin supplement
that contains approximately 10 µg (400 I.U) cholecalciferol. Pregnant women are often already taking a multivitamin
in order to meet requirements for folic acid and iodine, therefore this recommendation avoids the addition of an extra
There are currently no subsidised pre-natal multivitamins available, therefore this may be a barrier for some women.
Pregnant women, especially those at risk of deficiency, are recommended to eat foods rich in vitamin D and to receive
Elevit with Iodine contains 12.5 µg (500 IU) cholecalciferol per
tablet. Several other pre-natal vitamins contain cholecalciferol, but at lower than recommended doses.
ACKNOWLEDGEMENT: Thank you to Dr Helen Patterson, Consultant in Obstetrics and Gynaecology, Senior
Lecturer, Dunedin School of Medicine and Dr Lisa Houghton, Lecturer, Department of Human Nutrition,
University of Otago for expert guidance in formulating the answer to this question.
- The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG). Pre-pregnancy counselling
and routine antenatal assessment in the absence of pregnancy complications. College Statement. RANZCOG, 2009.
- Munns C, Zacharin M, Rodda C, et al. Prevention and treatment of infant and childhood vitamin D deficiency in Australia
and New Zealand: a consensus statement. MJA 2006;185(5):268-72.
- U.S National Library of Medicine. MedlinePlus. Drugs and supplements: Vitamin D. Available from: www.nlm.nih.gov/medlineplus/druginfo/natural/929.html (Accessed
- Australian Government. Department of Health and Ageing. National Health and Medical Research Council. Ministry
of Health New Zealand. Nutrient reference values for Australia and New Zealand including recommended dietary intakes.
- Royal College of Obstetricians and Gynaecologists (RCOG).RCOG issues new guidance on vitamin supplementation in
pregnancy. RCOG Press Release. RCOG, 2009. Available from: www.rcog.org.uk (Accessed
- National Institute for Health and Clinical Excellence (NICE). Antenatal care: routine care for the healthy pregnant
woman. NICE, 2008. Available from: www.nice.org.uk (Accessed
- Hollis B, Johnson D, Hulsey T, et al. Vitamin D supplementation during pregnancy: double blind, randomised clinical
trial of safety and effectiveness. J Bone Min Res 2011; [Epub ahead of print].