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The Use During Pregnancy of Prescription, Jennifer Bercaw, MD, Bani Maheshwari, MD, and Haleh Sangi-Haghpeykar, PhD Background: Despite lack of scientific evidence about the safety of comple- mentary and alternative medicines, the reported use of such remedies during pregnancies hasincreased. This study was undertaken to investigate the use of herbs, vitamins, and over-the-counter and prescription medications among pregnant Hispanic women and reasons for use,and to assess physician–patient level of communication about women’s use. Methods: A totalof 485 Hispanic women were surveyed by means of a self-administered questionnaire immedi-ately postpartum in a public hospital in Houston, Texas. The primary outcome was use of alter-native therapies during the prenatal period. Results: During their pregnancies, 19 percent ofthe participants took herbs and 47 percent took vitamin supplements, other than prenatal vita-mins. The most common reason for using herbs and vitamins was to improve the woman’s gen-eral health and energy level (59%); a few women (12%) had used them for specific pregnancy-related problems. Overall, 77 percent took prenatal vitamins and 21 percent supplemented withfolic acid. The rates of use of over-the-counter and prescription medications were 23 and 29percent, respectively. The use of prescription medication was two-and-a-half times higheramong women with history of medical problems (adjusted OR = 2.59, 95% CI = 1.59–4.25,p = 0.0001). No other factor studied was independently associated with supplement or medica-tion use. One in five women (20%) believed that herbs and vitamins were safer to use than pre-scription medication or were better at treating medical problems than prescription medicine,and one-third had not disclosed information about supplement use to their physicians. Conclu-sions: Use of herbal remedies does not appear to be a replacement for conventional medicineamong most pregnant Hispanic women. Patient education about the risks of alternative thera-pies may lead to a reduction in intake of alternative medicines and greater disclosure to medi-cal practitioners among this ethnic group. (BIRTH 37:3 September 2010) Key words: herbs, Hispanics, over-the-counter medications, pregnancy, prescription medica-tion, vitamins Despite lack of scientific evidence concerning the safety Previous studies suggest that 4 to 62 percent of pregnant of complementary and alternative medicines and their women use some form of herbal and alternative thera- concomitant maternal and fetal effects, the reported use pies and between 29 and 93 percent use over-the-counter of such remedies during pregnancies has increased.
medication during their gestation (1–5). Variation exists Jennifer Bercaw is a Clinical Postdoctoral Fellow at Department Address correspondence to Haleh Sangi-Haghpeykar, PhD, Associate of Obstetrics and Gynecology, Baylor College of Medicine, Hous- Professor, Department of Obstetrics and Gynecology, Baylor College ton, Texas; Bani Maheshwari is a Resident in the Department of of Medicine, 1709 Dryden Road, Houston, TX 77030, USA.
Obstetrics and Gynecology, Weill Cornell Medical College, NewYork Presbyterian Hospital, New York City, New York; and Haleh Sangi-Haghpeykar is an Associate Professor at Department ofObstetrics and Gynecology, Baylor College of Medicine, Houston, Journal compilation Ó 2010, Wiley Periodicals, Inc.
by population studied, and higher rates of use are seen within 10 percent of the true value, we planned to survey among older women of higher socioeconomic status and 490 women (13). Approximately, 10 percent of the eligi- ble women who were approached declined to take part Currently, all published research on the use of herbal in the study. No information is available on nonpartici- remedies, vitamins, and over-the-counter medications during pregnancy has been conducted exclusively on A three-page questionnaire obtained information on non-Hispanic populations. Moreover, research is lacking demographic and constitutional factors (e.g., age, coun- about why Hispanic women may engage in alternative try of birth, preferred language, education, and marital medicine use during pregnancy and if they disclose such status), reproductive history (gravidity, parity, and abor- use to their health care practitioner. Data from National tions), history of medical problems, obstetric factors Health Interview Survey indicate that Hispanics have (gestational age, pregnancy weight gain, and adequacy the highest provider nondisclosure rates (68.5%), fol- of prenatal care), and plans for breastfeeding.
lowed by non-Hispanic blacks (65.1%), and non- A checklist of supplements and herbal preparations Hispanic whites (58.1%) (9). Use of alternative was included. Participants were also asked to provide medicine during pregnancy and lack of disclosure to a names for any other supplement or preparation they may physician may predispose the developing fetus to sub- have taken. The list of vitamin supplement included pre- stantial risk for harmful effects. A recent review on the natal vitamins, iron, folic acid, vitamins B6, B12, D, E, topic concluded that lack of data on prenatal use of com- C, and any other specified by the participant. The list of plementary medicine among different ethnic groups herbal remedies included chamomile, garlic, aloe vera, within a particular country was a major research gap in ginger, cat’s claw, Naielito, Echinacea, blue cohosh, the literature (10). Overall, Hispanics are the fastest black cohosh, cod liver oil, St John’s wort, Gingko growing segment of the United States population (11), biloba, and any other supplement specified by the partic- primarily as a result of high fertility rates (12).
ipant. Use of over-the-counter medications was also The objectives of this study were to investigate the assessed, including acetaminophen, ibuprofen, aspirin, prevalence of use of herbs and vitamins, over-the-coun- Pepto Bismol, Maalox, Robitussin, Benadryl, Sudafed, ter medications, and prescription medications among Mucinex, laxatives, and any other medication specified pregnant Hispanic women. We also investigated reasons by the participant. To ascertain the use of prescription for use, and physician–patient level of communication medication, women were asked if a physician had pre- scribed any medication during pregnancy, the type, andreason for doing so.
Questions were also asked about the place where herbs and vitamins were purchased (drug store, healthfood store, grocery store, obtained from family or A cross-sectional study was conducted among pregnant friends), and reasons for using them. Views and attitudes women planning to give birth in a public hospital in about herb and vitamin use were assessed by the follow- Houston, Texas. All postpartum women were invited by ing questions: (a) I think herbs and vitamins are safer to a bilingual staff member to participate in the survey dur- use than prescription medications; (b) I think herbs and ing their postpartum inpatient hospital stay. After pro- vitamins are better at treating my medical problems than viding their informed consent, each participant was prescription medications; and (c) I would use herbs and asked to complete a self-administered questionnaire, vitamins if my doctor told me more about them.
available in English and Spanish. The questionnaire took Response to each question was based on a five-point approximately 15 minutes to complete. A Spanish- Likert scale ranging from ‘‘strongly agree, somewhat speaking clinic staff member was available to answer agree, neutral, somewhat disagree, strongly disagree.’’ patients’ questions. To ensure confidentiality, the ques- Finally, information was obtained on whether women tionnaire did not include patient’s name or any other had told their physician or not about any alternative identifying information. Women were not paid for par- medicine use and how their physician reacted to this ticipating in the study. The study was approved by the Institutional Review Board for Human Subject Research Descriptive statistics (frequencies, percentages) were used to summarize the data. Using separate models, we Sample size calculation was based on the study’s pri- compared herb and vitamin users and over-the-counter mary objective, that is, to provide an estimate of herb and prescription medication users with nonusers on vari- and vitamin use among pregnant Hispanic women. We ous constitutional and medical characteristics using Stu- had hypothesized that this rate would be between 40 and dent’s t test and chi-squared analysis. Finally, we 50 percent. Based on this assumption and to be 95 per- examined predictors of use by multivariate analysis, cent confident that the resulting estimate would fall where influence of potential confounders was controlled for by means of logistic regression analysis. A value of p < 0.05 was considered statistically significant. Allanalyses were performed using SAS System statistical Of 485 Hispanic women who were surveyed, most were young (mean age 26 yr), of low educational attainment (68% had no high school diploma), and uninsured (73%). Overall level of acculturation was low—93 per- cent were born outside the United States (most com- monly in Mexico), and most women (86%) considered Spanish as their primary language. Approximately half (49%) of the participants received early prenatal care, defined as care received within the first 3 months of pregnancy. Over 90 percent planned to breastfeed their child, and the planned average time for breastfeeding Two of three Hispanic women surveyed (64%) had taken some form of herbal remedy or vitamin supple- ment, other than prenatal vitamins, during their pregnan- cies (Table 2). The most common reasons for using herbs and vitamins included to improve general health (38%) and to increase energy (21%). A few women (12%) used herbs for specific problems, including ane- mia, allergies, hypertension, and gastrointestinal symp- toms. Most vitamins and herbs were purchased at a pharmacy (78%). Two of three women (66%) told their health care practitioner about their use of herbs and vitamins; in most cases, the practitioner reacted posi- The specific herbs and vitamins that women used are shown in Table 2. The most common herbal supplement used was chamomile; no one reported the use of blue and black cohosh, Gingko biloba, St John’s wort, or cat’s claw. With respect to vitamin supplements, 77 percent of women reported using prenatal vitamins during pregnancy. Other commonly used supplementswere iron and folic acid, which were used by nearly one-third of respondents; all other vitamins were used by less Pepcid, although two-thirds of the women were unable than 5 percent of the women surveyed (Table 2).
to give the name of the medication they took.
Approximately one-fourth (23%) of the women had Women were asked three questions to assess their used over-the-counter medications during their preg- views and attitudes about alternative medicine use.
nancy (Table 3). Acetaminophen was the most common About one in five women agreed (strongly or somewhat type (13%), followed by other nonsteroidal anti- strongly) with the statement that ‘‘Herbs and drugs are inflammatory drugs (NSAIDs), such as ibuprofen and safer to use than prescription medication’’ (22%) and aspirin. Over-the-counter cold preparations, such as ‘‘Herbs and vitamins are better at treating medical prob- Robitussin and Benadryl, were used by 6 and 3 percent lems than prescription medication’’ (20%). In addition, of participants, respectively. Nearly one in three women reliance on the doctor’s advice was high—50 percent (29%) was given some form of prescription medication agreed with the statement: ‘‘I would use herbs and vita- in their pregnancy, most commonly for urinary tract mins if my doctor told me about these alternatives.’’ infections and diabetes. The most common prescriptions Next, we examined the use of herbs and vitamins as given were glyburide, insulin, Macrodantin, Sular, and well as over-the-counter and prescription medication use Table 2. Use of Herbs and Vitamins During Pregnancy Table 3. Use of Over-the-Counter and PrescriptionMedications During Pregnancy Took herbs ⁄ vitamins during pregnancy? *A large percentage of respondents were unable to give the ‘‘actual’’name of prescription medication taken.
From where were herbs ⁄ vitamins purchased? and early initiation of prenatal care. Prescription medi- cation use was more prevalent among women with a his- Multivariate modeling was performed in which we systematically examined for variables that univariately If you used herbs ⁄ vitamins, did you tell doctor? were shown to be related to herbs and vitamins use and over-the-counter or prescription medication use, control- ling for any factor that was thought to be a potential con- If you told doctor, how did he ⁄ she react? founder. The variables that were included in the final models were place of birth (U.S. born or not), education, timely care, history of medical problems, age, and parity. Results of this analysis showed that prescriptionmedication use was over twice as high among women by various patient characteristics (Table 4). Women with a history of medical problems as opposed to those who took herbs and vitamins were slightly younger than without such problems (adjusted OR = 2.59, 95% CI: nonusers, although the two groups were similar with 1.59–4.25, p = 0.0001). No other factor studied was respect to all other characteristics studied. Factors asso- independently associated with herbal supplement, over- ciated with over-the-counter medication use were high the-counter, or prescription medication use in the multi- level of education, having been born in United States, Table 4. Use of Herbs and Vitamins, Over-the-Counter, and Prescription Medications During Pregnancy by HispanicWomen and Patient Characteristics *Early care is defined as having started prenatal care within the first 3 months of pregnancy.
natal vitamins) during their pregnancy, most often forurinary tract infection and diabetes. The largest study of This study is the first report of use of vitamins and herbal this issue to date reported that of women enrolled in supplements as well as over-the-counter medications eight health maintenance organizations in the United among pregnant Hispanic women. The harmful effects States, during their pregnancy 64 percent were pre- of over-the-counter medications to the developing fetus scribed a medication, many of which had no evidence are known. Salicylates, including aspirin, have been of safety for use during pregnancy (19). Variations in prescription drug use have been reported by patient decreased birthweight, prolonged gestation, and pro- characteristics (20), including ethnicity (21,22). In a longed labor (15). Use of ibuprofen during pregnancy longitudinal study of pregnant women in the San Fran- may be a risk factor for premature closure of the fetal cisco Bay area, prescription drugs were given to 47, 58, ductus, persistent pulmonary hypertension of the new- and 72 percent of white, Hispanic, and black women, born, fetal nephrotoxicity, periventricular hemorrhage, respectively (22). The lower rate of use of prescription and gastroschisis (16–18). The rates of use of ibuprofen drug in our sample (mostly non-U.S. born Hispanics) and aspirin in this study were 4 and 3 percent, respec- may be expected because it has been reported that for- tively, both lower than those in non-Hispanic cohorts eign-born women are less likely to be given a prescrip- (3,4). Overall, one in four pregnant Hispanic women tion medication than are their United States-born (23%) in this study had taken some form of over-the- counterparts (22). It is unknown if this finding is a result counter medication. Higher use of over-the-counter of less access to care, or whether, because of cultural dif- medication has been reported among non-Hispanics, and ference, foreign-born women are more likely to tolerate rates as high as 63 percent among African-Americans their pregnancy-related problems and not seek a pre- (4), and 93 percent among whites (3).
scription medication. Overall, data from this study and With respect to prescription medication, 29 percent of others indicate that prescription medication is used dur- our sample was prescribed a medication (other than pre- ing pregnancy. As a result, the U.S. Food and Drug Administration is revising its pregnancy labeling system likely to take folic acid every day before pregnancy to better reflect reproductive and developmental risks to compared with non-Hispanic white and black women the growing fetus associated with drug use (23,24).
(36). It is recommended that all women planning a preg- The use of herbs in pregnancy is of significant impor- nancy consume 0.4 mg of folic acid daily before preg- tance for the medical community, not only because of nancy and in the first trimester (37).
the potential toxicity of the herbs themselves, but also Whether pregnant Hispanic women disclose their because of possible herb-drug interactions. Overall, the medication use to their health care practitioners or not is prevalence of herb use among the Hispanic women in not known. Our study showed that one-third of herb and our study (19%) was higher than the available reports vitamin users had not informed their physician about for black pregnant women (4%) (3), but lower than Uni- their supplement usage. This rate is lower than that ted States whites (45%) (3) or the European cohorts reported in past research among nonpregnant Hispanic women, of whom 85 percent indicated not telling their None of the women in our sample reported use of doctor about all the remedies they used (38). Although herbs linked to adverse affects in pregnancy, including pregnant women may be more inclined to inform their Gingko biloba, St John’s wort, or blue cohosh. Ginkgo doctor about supplement use, at least one in three do not biloba is suggested to have anti-platelet activities and, do so. These data are consistent with past research show- hence, may be unsafe in pregnancy, in particular during ing that about 24 percent of obstetrician-gynecologists labor (25). St John’s wort has been shown to affect the do not always ask their patients about alternative medi- CYP450 enzymes causing subtherapeutic serum levels cation use (39). Because little data are available on the of other medications being used simultaneously (26).
safety of most herbal supplements in pregnancy and the Furthermore, a case report presented evidence of perina- interaction among herbs and conventional medicines, tal stroke in an infant born to a woman who had con- health care practitioners need to be well informed about risks associated with use of herbs and vitamin during induction) (27). Our data provide evidence that the moti- pregnancy, to be aware of such use by many pregnant vation among Hispanic women to employ herbal reme- women, and to incorporate ways to question women dies and vitamin supplements does not appear to be a about alternative medicine use during prenatal visits.
replacement for conventional medicine. Indeed, similar Our data have some limitations. Participants were to nonpregnant Hispanic women (28,29), most pregnant seen in public clinics and were, therefore, economically women in our study used herbs and vitamins to augment disadvantaged. Most study participants were non-United their general health. This notion is further confirmed by States born, specifically from Mexico. Because health- our observation that only a few women (one in five) in related practices and attitudes may differ by national our sample believed that herbs and vitamins were safer origin (e.g., Mexico, Puerto Rica, and Spain), and socio- to use or were more effective at treating medical prob- economic status, broad generalizations to all Hispanic women may not be possible. We did not ascertain which Although vitamin use in the United States has steadily trimester of pregnancy any herbs, vitamins, and various increased over the past two decades (30), growing evi- medications (prescription or over-the-counter) were dence suggests that many vitamins may be unsafe for taken—information that is needed to understand fully use in pregnancy. A recent review showed that women the spectrum of potential harm to fetus. In addition, our supplemented with vitamin C compared with placebo survey was based on self-reports and the assumption that were at increased risk of giving preterm birth (31). Fur- the participants fully understood the questions and were thermore, lower birthweight has been observed among unbiased in their reporting. To minimize the tendency of infants of women supplemented with vitamins E (32), false responses, the surveys were anonymous. Further- C (33), or D (34) compared with those who were not more, a bilingual nurse or staff member was available at supplemented with these vitamins. The rate of supple- the clinic to answer questions from respondents.
mentation with vitamins D, E, and C in this study was It should be noted that ascertainment of information small (<5%). With respect to prenatal vitamins, 77 per- through self-report, as opposed to a medical chart, has cent of the women in this study took prenatal vitamins, a certain advantages. Some medications may be pre- rate substantially lower than the reported rate of 92 per- scribed, but not included in the medical charts, or be cent for white subgroups in the United States (3). More- prescribed (and included in the chart), but not used by over, folic acid supplementation during pregnancy was lower in our group (21%) than that described in the Despite these limitations, this study presents valuable available reports in other countries, including 79 percent information about the extent of alternative therapy use in Australia (5) and 69 percent in Hungary (35). Within among Hispanic women. Future qualitative studies are the United States, Hispanic women have been reported needed to measure psychosocial and attitudinal domains, to have a higher rate of neural tube defects and are less including interaction between acculturation, familial, and social networks, to truly understand the underlying 9. Graham RE, Ahn AC, Davis RB, et al. Use of complementary and reasons for use of specific therapies among Hispanic alternative medical therapies among racial and ethnic minorityadults: Results from the 2002 National Health Interview Survey.
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