In this study, we assessed the use of herbal medicines during pregnancy and delivery. We also examined factors associated with the use of herbs among mothers who delivered in the preceding two years in Tabora, central Tanzania. The findings show that use of herbal medicines during pregnancy or delivery was very high (60%). Significant factors associated with the use of herbs were long distance to the nearest health facility, perception that herbal use was safe and whether health care providers discouraged use of herbal medicines or not during antenatal visits.
The level of use of herbal medicine is similarly high in a number of other studies in sub-Saharan Africa, Asia and Middle East, where the proportions of use have been observed to range between 20–80% [5, 6, 14–16]. Findings in all these studies ratify dramatic increment in the use of herbal medicines in pregnancy and delivery. These same countries are however, also reporting high maternal and newborn morbidity and mortality. On the other hand, a recent analysis of data from the Tanzania Reproductive Health Survey which involved 3530 women of reproductive age (15–49 years) found a herbal use rate of 10.9% [17]. This proportion is lower than what has been documented in many related studies. The difference could perhaps be attributed to the larger sample size and the use of secondary data as most of the other surveys used primary data and covered fewer respondents. Although the coexistence of herbal medicine use and high maternal and newborn mortality could be coincidental, the high unchecked use of herbs should invite a concern. It is even more serious as the unproven perceived safety can lead to rapid increase in promotion of traditional medicines in the society as well as the media. It is common to see posters advertising traditional medicines and herbalists in various parts Tanzania. In such advertisements, herbal medicines are often promoted as natural and safe, attracting their wide use, especially among pregnant women who are concerned about the whole process of childbirth and health of the unborn child.
A significant association has been documented between education status of a woman and utilization of herbal remedies during pregnancy and delivery. For example, some studies in Africa suggest that women of low educational status as compared to those highly educated had a higher likelihood of using herbal remedies [18, 19]. However, the current data do not support such an association. It is important to note that factors associated with use of herbs may vary from one area to another depending on the type of study and population involved.
Plants used for herbal remedies are less expensive as compared to modern medicines and they have been culturally considered as an effective and acceptable option even when modern health facilities are available [20]. Similar to observations elsewhere, use of herbal medicines in this study is significantly associated with perceived beliefs about their safety [21] and local availability [20–22]. Some studies have associated use of herbs during pregnancy and delivery with lack of access to public health care [3]. In our study, women who resided far away (at least 5 km) to the nearest health facility had more than 10% adjusted prevalence ratio to use herbal medicines compared to women living closer to the health facilities. This may suggest that accessibility to public health care is an important attribute to using herbs during pregnancy, similar to observations in other areas [3, 18, 23]. Distance to the nearby health facility has been quite often given as major reason for women to deliver under the care of unskilled attendants. Such deliveries by unskilled attendants may be compounded by use of medicinal herbs while there might also be silent exposures even when a birth takes place in a health care facility.
Whereas response to such high exposures to herbs would be required, the most important concern is lack of awareness and knowledge of pregnant women [9] and the community about potential effects of using herbal medicines on the mother and the fetus [3, 24]. In the current study, less than half of the respondents were aware of the adverse effects of herbs in pregnancy and only a few of them were able to mention some of the major effects. In Ethiopia and Norway for example, merely 14% and 12% respectively of pregnant women reported to have received health advice from healthcare workers on the use of herbs [19, 20]. Compared to women who were discouraged by health care providers against the use of herbs during pregnancy, significantly more women in the Tabora study who did not receive such advice used herbs (p < 0.01). This finding suggests that if women get appropriate information during pregnancy they will greatly evade using herbs.
Oral or vaginal administration of herbal medicine may lead to systemic presence of the medicines and consequently exposures to the unborn child. Similar to studies in Ghana [10] and Ethiopia [18], oral route was the commonest means (64.9%) for taking herbs during pregnancy and labour in the current study. In all these studies, women most often chewed or consumed herbs as a strong tea. On the contrary, findings in a related study in a referral hospital in rural north-western Tanzania revealed that less than a fifth of women reported using herbs orally [25]. However, that study looked at only women who used herbs for inducing abortion.
The main motive for using herbs in the current study was to shorten labour duration (38.9%). For many years, women used herbal medicines in pregnancy to sort out several conditions during pregnancy and the delivery process. Similar to findings in Tabora, studies indicate that pregnant women in some communities use herbs for the purpose of easing pain, accelerating labour, preventing antepartum and postpartum haemorrahage, increasing milk production, and aiding postpartum uterine involution [7, 15, 26]. The grounds for the high usage of herbs could in addition be attributed to their easy accessibility, perceptions that they are safe; as well as the general lack of awareness of the potential side effects [18, 24, 27]. Thus exposure to herbal medicines in pregnancy is not only during unskilled attendance but it takes place even when a pregnant woman is being prepared to a facility for skilled attendance birthing.
Perceived safety of the herbs and the stance of health care providers towards use of the herbs were significant correlates of herbal use among the respondents in the current study. The statistically significant association between perception of safety and use of herbal remedy during pregnancy is in line with the findings of various related studies elsewhere [12, 14, 28]. These studies indicate that pregnant women who perceive herbal remedies as being safe tend to use them more than their colleagues who perceive them otherwise.
This study has several potential limitations which should be acknowledged to enable readers construe the findings. First, although we assumed that mothers who gave birth within the preceding two years were likely to remember use of herbal medicines in their most recent pregnancy and delivery; we are unable to completely rule out the possibility of information bias due to individual’s ability to recall. If some of women were unable to remember, this bias could have contributed to the low estimates. Second, some women were aware that use of herbal medicine during pregnancy was discouraged by health care providers. Therefore, due to social desirability bias, there is a possibility that some women concealed reporting use of herbal medicines, thus, leading to under-estimating the proportion of herbal use. Third, there is possibility that the variables we considered as independent may not be exhaustive. Despite all these, to our knowledge, this is the first study to attempt to look at herbal medicine use during pregnancy and delivery as a forgotten exposure when adopting strategies to attain SDG 3 target on reduction of maternal and newborn mortality