Table 5 Documentation on safety of most frequently used herbs during pregnancy
Sr. | Herb (or mixture) | Study subjects in references studies | Documentation on safety |
|---|---|---|---|
Safe to use in pregnancy | |||
1 | Ginger (Zingiber officinale) | Human | Clinical evidence in human pregnancy have not found any harmful effect to mother or fetus [28, 50, 51]. |
2 | Garlic (Allium sativum) | Human | Studies in human pregnancy have shown no adverse effect of garlic [24, 52]. |
3 | Dates (Phoenix dactylifera) | Human | One prospective human study did not report any harmful effect on mother and fetus [53]. |
4 | Olive (Olea europaea) | Human | Clinical human evidence have not found any harmful effect to mother or fetus [54, 55]. |
5 | Coconut oil (Cocos nucifera) | Human | No health hazards are reported in conjunction with the use of coconut oil as food or drug or even in raw form [28]. |
6 | Aloe (Aloe vera) | Human | Topical application by pregnant women is unlikely to be harmful [29]. However, it should not be taken orally during pregnancy as the aloe latex contains anthraquinones that may stimulate uterus and initiate premature labor or possibly cause abortion [28]. |
7 | Peppermint (Mentha piperita) | Human | Evidence in human pregnancy following use as tea has not shown any harmful effect to mother or fetus [16, 25,26,27]. Excessive dose should be avoided due to its emmenagogue properties [28]. |
8 | Aniseed (Pimpinella anisum) | Human | Safe to use in human pregnancy with normal doses [16, 25, 26]. It increases the action of warfarin, so it is not recommended for women on warfarin [56]. |
9 | Olibanum (Frankincense - Boswellia sacra) | Human | Not harmful to human mother or fetus in moderate doses for mild ailments [25]. Its resin in high doses is an emmenagogue and may induce abortion [29]. |
10 | Chamomile (Matricaria chamomilla) | Human | Can be safely used as tea in moderate amounts during in human pregnancy [16, 25, 27]. It may act as a uterine stimulant, so large doses in pregnancy should be avoided [29]. Prolonged use has been related with premature constriction of fetal ductus arteriosus [57]. |
11 | Quince (Cydonia oblonga) | Human | A recent controlled study has shown benefit against mild nausea and vomiting in human pregnancy without any adverse effect [58]. |
12 | Green tea (Camellia sinensis) | Human | Safe to use as tea in moderate quantity [16]. Pregnant women are recommended to avoid large quantities due to the caffeine content [28]. |
13 | Eucalyptus (Eucalyptus globulus) | Human | Should only be used topically [16, 25]. In rare cases, oral ingestion may cause nausea, vomiting and diarrhea [30]. Due to known toxicity and unknown effects during pregnancy, its ingestion should be avoided [29]. |
Use with caution | |||
1 | Basil (Ocimum basilicum) | NA | It has not been studied in human pregnancy and should not be used in doses higher than commonly found in food [16, 25]. |
2 | Greater plantain (Plantago major) | NA | The herb has not been studied in human pregnancy, although no harmful contents have been identified. Therefore, it can be used but with caution [16, 25]. |
3 | Oregano (Origanum vulgare) | NA | It has not been studied in human pregnancy and should not be used in doses higher than commonly found in food [16, 25, 27]. |
4 | Castor oil (Ricinus communis) | Human | Human studies have indicated use of castor oil to induce labor, however, it should not be used without proper supervision of a qualified health care practitioner [25]. Over dosage can lead to severe gastric irritation with vomiting, colic and severe diarrhea [28]. |
5 | Jujube (Zyzyphus jujube) | NA | No scientific report available on its use and safety during pregnancy. Evidence regarding safety has not been conclusively established [25]. Therefore, it should be only used in pregnancy with supervision of a qualified health care practitioner. |
Information unavailable about safety in pregnancy | |||
1 | Flixweed seed (Descurainia sophia) | NA | No scientific report available on its use and safety during pregnancy. |
2 | Black seed (Nigella sativa) | NA | No scientific report available on its use and safety during pregnancy in humans. Traditionally believed to slow down or stop uterus from contracting if taken in doses higher than commonly found in food. |
3 | Kacip Fatimah (Labisia pumila) | NA | No scientific report available on its use and safety during pregnancy. |
4 | Cumin (Cuminum cyminum) | NA | Information regarding safety in human pregnancy is lacking. In India, it is used as an abortifacient [28]. Large doses in animal studies have shown antifertility activities [59]. Therefore, doses higher than commonly found in food should be avoided. |
5 | Chicory (Cichorium intybus) | NA | Not studied in human pregnancy, so the safety has not been conclusively established [25, 26]. |
6 | Borage (Borago officinalis) | NA | Information regarding safety in human pregnancy is lacking [25]. Should be avoided during pregnancy due to possible teratogenic and labor inducing effects of prostaglandin E agonists [60]. |
7 | Alyssum (Lobularia maritima) | NA | No scientific report available on its use and safety during pregnancy. |
Potentially harmful in pregnancy | |||
1 | Pennyroyal (Mentha pulegium) | Human | Use of the volatile oil in pregnancy is not recommended as it has been reported to cause abortion if taken in high doses; cases of death have been reported following misuse of its volatile oil to induce abortion [28]. It contains potentially toxic compound pulegone and should be avoided [25]. |
2 | Licorice (Glycyrrhiza glabra) | Human | Not recommended during pregnancy because of possible alterations of hormone levels and the association with preterm delivery [27,28,29,30, 39]. |
3 | Sage (Salvia officinalis) | Human | Not to be used during pregnancy due to abortifacient properties [16, 27, 28]. The pure essential oil and alcoholic extracts should not be taken during pregnancy [30]. |
4 | Ammi (Ammi visnaga) | NA | Human or animal studies not available in current literature but its active constituent, khellin, has uterine stimulating activity; therefore, it is contraindicated during pregnancy [61]. |
5 | Thyme (Thymus vulgaris) | NA | Human or animal studies not available in current literature but potentially harmful due to its abortifacient activity [16, 25, 26]. |
6 | Fenugreek (Trigonella foenum-graecum) | Animal | Evidence suggests abortifacient effects as one animal study showed stimulating effects on uterus [25, 27]. It also possesses hypoglycemic, hypolipidemic and hypothyroid properties [16]. |
7 | Cinnamon (Cinnamomum verum) | Animal | Animal evidence suggests possibility of fetal malformation following ingestion of its essential oil [16, 25]. Should only be used in doses commonly found in food. |
8 | Egyptian willow (Salix aegyptiaca) | NA | No human or animal study found for this particular herb. No safety data on use during pregnancy exists for its counterpart white willow. Nevertheless, consumption of both of these in pregnancy should be avoided as these contain salicylates which can cross the placenta [16, 25]. |