16 August 2013
CHOICE reports that while over one third of pregnant women are taking herbal medicines,  many may be unaware of the potentially harmful side effects. 10% are not taking the recommended doses of folic acid and iodine.
"Given some herbs are capable of causing adverse pregnancy outcomes such as miscarriage, preterm labor and birth defects it is crucial pregnant women educate themselves on potential impacts on their health”, says CHOICE spokeswoman Kate Browne.
“There is a widespread perception that these products are natural and therefore safe. Talking to your doctor about what herbal medicines and supplements you are taking is your best bet in reducing health risks.”
A CHOICE shadow shop found that some products recommended by pharmacy and health food store assistants for morning sickness, including Blackmores and Nature’s Own ginger tablets for travel sickness, provided no dosing instructions for pregnant women, potentially leading to doses exceeding the safe maximum of 1 to 2g per day. Large doses can cause thinning of the blood and heartburn. CHOICE recommends pregnant woman:
Watch their vitamin A intake, which can be toxic when taken at high levels. Intake of pre-formed vitamin A (retinyl palmitate) below 10,000 IU or 3000mcg is recommended.
Avoid excessive vitamin B6 intake as it has been linked to birth defects involving the baby's arms, legs and nerve development. The recommended daily intake is only 1.9mg, however some B6 preparations recommended to relieve nausea and vomiting can be up to 75mg. The recommended dose for pregnant women is 50mg. High doses of B6 are found in some pregnancy multivitamins, so ensure you're not doubling up if you're also taking it for morning sickness.
“Pregnancy multivitamins may have all the supplementary support that you need. Be sure to check the B6 dosage listed as you may not need to take an additional supplement,” says Ms Browne.
A CHOICE shadow shop of health food stores and pharmacies found that while all of them recommend folic acid, only half recommended iodine, and only two of the 15 stores cautioned about vitamin A intake, which can be toxic when taken at high levels. A few shops acknowledged herbal medicines and essential oils can be dangerous, and that it may be best to avoid them.
“Advice on vitamins and minerals was mixed, highlighting the need for pregnant shoppers to educate themselves before purchasing supplements.This may have been due to the casual encounter of the shadow shop more than any shortcoming. The fact they pointed it out at all is to be commended,” said Ms Brown.
“A healthy diet is generally enough to ensure pregnant women and their foetuses receive adequate vitamins and minerals, but the two supplements recommended for all pregnant women are folic acid and iodine.”
The Royal Women’s Hospital in Melbourne recommends caution with the herbal medicines listed in the box below.
||While OK as a topical gel, aloe vera latex taken orally in powder or liquid form may cause low blood sugar, uterine contractions or miscarriage. There’s not enough information about safe doses in pregnancy, so it’s probably best to avoid aloe vera juice and supplements.
||May cause early labour, so avoid in early pregnancy.
|Evening primrose oil
|Limited safety information.
||While OK to use in normal quantities in cooking, larger quantities found in supplements may cause miscarriage or early labour.
||As used in a cooking is fine, but avoid large doses in supplements, as they may cause bleeding, miscarriage or early labour.
||OK in cooking and in supplement doses of 1 to 2g per day. Large doses can cause thinning of the blood and heartburn.
||Should be avoided during pregnancy, especially early pregnancy, as it can cause serious adverse events.
|Liquorice in large quantities, as in liquorice extract or liquorice root
|Can cause miscarriage and early labour. Black liquorice sold as confectionery may contain the extract, or may be flavoured with aniseed.
|Is said to help reduce labour, although there’s little evidence to support this, nor is there much information about its safety. Avoid in early pregnancy.
|Little is known about its safety during pregnancy, so it’s best to avoid it or seek advice from your doctor.
|St John's Wort
|May reduce birthweight, and interferes with certain medicines. Talk to your doctor before taking it while pregnant.
||There’s a lack of safety information about taking it in pregnancy. Talk to your doctor first.
 Frawley J, Adams J, Sibbritt D, Steel A, Broom A, Gallois C. Prevalence and determinants of complementary and alternative medicine use during pregnancy: Results from a nationally representative sample of Australian pregnant women. Aust N Z J Obstet Gynaecol. 2013 Aug;53(4):347-52.
 To learn more about what health stores and pharmacies recommended to pregnant women, CHOICE sent a shadow shopper to 15 different stores throughout Sydney. The shopper told shop assistants she was six to eight weeks pregnant and suffering from morning sickness, and asked if there as anything they could recommend to help relieve nausea.