Therapeutic drug use during pregnancy: a comparison in four European countries. OECM Working Group. Occupational Exposures and Congenital Anomalies

Evaluation of the pregnant women's approaches regarding drug utilization

OBJECTIVE:

Drug utilization habits of the pregnant are a critical aspect of rational use of the medicine (RUM). This study aimed to analyze the RUM related attitudes and the behaviors of women during their pregnancies.

METHODS:

The data were collected between May 2016–October 2016 by conducting surveys to 71 pregnant women admitted to the private and governmental hospitals in five districts of Northern Cyprus. The sociodemographic characteristics of the pregnant as well as their attitudes and behaviors concerning drug use were evaluated.

RESULTS:

The mean age and the gestational week of the patients was 29.7±4.3 years and 25.7±11.2 weeks, respectively. Planned pregnancies constituted 71.8% of all. The percentage of patients with an unplanned pregnancies who were using drugs at the time of the survey (25.0%) was lower than that in those with planned pregnancies (49.0%, p<0.05). Almost two-thirds (66.2%) of the women were exposed to a drug during pregnancy, mostly for “vitamin/mineral prophylaxis” (38.3%) and agents controlling nausea/vomiting (19.1%). Two out of eleven women (18.2%) were using folic acid when they learned about their pregnancy. One of the drugs used for the chronic disorder in the third trimester was acetylsalicylic acid (11.1%), a category D drug in this setting. Most of the patients stated that they frequently read the instructions (60.9%), “often” paying attention to side effects (56.5%). Considering some of the habits related to drug use, 8.7% and 10.9% of pregnant women declared that they sometimes “did not follow the instructions” and “dosage/duration of the drug usage”, respectively. Seven patients (15.2%) declared that they did not consider side effects on the medication guide while more than half (56.5%) did it “often”. Near one in five (19.6%) of the pregnant women stated that they hesitated about the drug usage due to teratogenicity risks.

CONCLUSION:

Our study highlights the drug utilization attitudes and behaviors of pregnant women during pregnancy in Northern Cyprus, indicating several shortcomings, including insufficient prenatal folic acid use, occasional use of risky drugs, and unsatisfactory medication guide handling. Available findings underline the necessity of education not only for patients but also for healthcare providers to disseminate RUM in pregnancy.

In vivo High-Content Screening in Zebrafish for Developmental Nephrotoxicity of Approved Drugs

Despite widespread drug exposure, for example during gestation or in prematurely born children, organ-specific developmental toxicity of most drugs is poorly understood. Developmental and functional abnormalities are a major cause of kidney diseases during childhood; however, the potential causal relationship to exposure with nephrotoxic drugs during nephrogenesis is widely unknown. To identify developmental nephrotoxic drugs in a large scale, we established and performed an automated high-content screen to score for phenotypic renal alterations in the Tg(wt1b:EGFP) zebrafish line. During early nephrogenesis, embryos were exposed to a compound library of approved drugs. After treatment, embryos were aligned within microtiter plates using 3D-printed orientation tools enabling the robust acquisition of consistent dorsal views of pronephric kidneys by automated microscopy. To qualitatively and quantitatively score and visualize phenotypes, we developed software tools for the semi-automated analysis, processing and visualization of this large image-based dataset. Using this scoring scheme, we were able to categorize compounds based on their potential developmental nephrotoxic effects. About 10% of tested drugs induced pronephric phenotypes including glomerular and tubular malformations, or overall changes in kidney morphology. Major chemical compound groups identified to cause glomerular and tubular alterations included dihydropyridine derivatives, HMG CoA reductase inhibitors, fibrates, imidazole, benzimidazole and triazole derivatives, corticosteroids, glucocorticoids, acetic acid derivatives and propionic acid derivatives. In conclusion, the presented study demonstrates the large-scale screening of kidney-specific toxicity of approved drugs in a live vertebrate embryo. The associated technology and tool-sets can be easily adapted for other organ systems providing a unique platform for in vivo large-scale assessment of organ-specific developmental toxicity or other biomedical applications. Ultimately, the presented data and associated visualization and browsing tools provide a resource for potentially nephrotoxic drugs and for further investigations.

Investigations on clonazepam-loaded polymeric micelle-like nanoparticles for safe drug administration during pregnancy

Medication during pregnancy is often a necessity for women to treat their acute or chronic diseases. The goal of this study is to evaluate the potential of micelle-like nanoparticles (MNP) for providing safe drug usage in pregnancy and protect both foetus and mother from medication side effects. Clonazepam-loaded MNP were prepared from copolymers [polystyrene-poly(acrylic acid) (PS-PAA), poly(ethylene glycol)-b-poly(lactic acid) (PEG-PLA) and distearyl-sn-glycero-3-phosphoethanolamine-N-[methoxy-poly(ethylene glycol) (PEG-DSPE)] with varying monomer ratios and their drug-loading efficiency, drug release ratio, particle size, surface charge and morphology were characterised. The cellular transport and cytotoxicity experiments were conducted on clonazepam and MNP formulations using placenta-choriocarcinoma-BeWo and brain-endothelial-bEnd3 cells. Clonazepam-loaded PEG₅₀₀₀-PLA₄₅₀₀ MNP reduced the drug transport through BeWo cells demonstrating that MNP may lower foetal drug exposure, thus reduce the drug side effects. However, lipofectamine modified MNP improved the transport of clonazepam and found to be promising for brain and in-utero-specific drug treatment.

[Drug therapy of otorhinolaryngological diseases in pregnancy : An update]

The majority of women take at least one form of medication during pregnancy. Due to often discrepant information about the risk assessment of pharmaceuticals during pregnancy, physicians are often beset by uncertainty with respect to prescription and the fear of medicolegal consequences is high. As prospective clinical trials on drug safety during pregnancy are prohibited due to ethical reasons and animal studies are of limited applicability to humans, drug recommendations often only rely on observational data. An objective examination of the topic not only contributes to effective treatment of illnesses in pregnancy but also prevents impairment of fetal outcome by omission of necessary maternal treatment. The aim of this article is to give a structured presentation of medications that can be used during pregnancy for treating medical conditions of the ear, nose and throat, in the sense of practical guidelines.

Treatment of nausea in pregnancy: a cross-sectional multinational web-based study of pregnant women and new mothers

BACKGROUND

The factors related to the treatment of nausea during pregnancy have not yet been investigated in several countries simultaneously. The present study aimed to describe differences in self-reported nausea during pregnancy and the patterns of use for both conventional and herbal medicines across countries. The factors related to nausea and its treatment and the relationships between different self-reported co-morbidities and nausea were also investigated.

METHODS

This cross-sectional study used data collected by a web-based questionnaire distributed between October 2011 and February 2012 in several countries within five regions: Western, Northern, and Eastern Europe, North America, and Australia. Women who were pregnant or had a child less than one year old were eligible to participate.

RESULTS

A total of 9113 women were included in the study, whereof 6701 (73.5%) had experienced nausea during pregnancy. Among respondents with nausea, conventional medicines were used by 1201 (17.9%) women and herbal medicines by 556 (8.3%) women. The extent of self-reported nausea and its treatment varied by country. Education, working status, and folic acid use were significantly associated with the use of conventional medicines against nausea. Respondents who had nausea also had a high burden of co-morbidity.

CONCLUSION

The prevalence of nausea was high across all participating countries but its treatment varied, possibly due to cultural differences and differences in attitudes towards medicines. A high degree of co-morbidity was found among respondents with nausea.

The rights and wrongs of blood-brain barrier permeability studies: a walk through 100 years of history

Careful examination of relevant literature shows that many of the most cherished concepts of the blood-brain barrier are incorrect. These include an almost mythological belief in its immaturity that is unfortunately often equated with absence or at least leakiness in the embryo and fetus. The original concept of a blood-brain barrier is often attributed to Ehrlich; however, he did not accept that permeability of cerebral vessels was different from other organs. Goldmann is often credited with the first experiments showing dye (trypan blue) exclusion from the brain when injected systemically, but not when injected directly into it. Rarely cited are earlier experiments of Bouffard and of Franke who showed methylene blue and trypan red stained all tissues except the brain. The term “blood-brain barrier” “Blut-Hirnschranke” is often attributed to Lewandowsky, but it does not appear in his papers. The first person to use this term seems to be Stern in the early 1920s. Studies in embryos by Stern and colleagues, Weed and Wislocki showed results similar to those in adult animals. These were well-conducted experiments made a century ago, thus the persistence of a belief in barrier immaturity is puzzling. As discussed in this review, evidence for this belief, is of poor experimental quality, often misinterpreted and often not properly cited. The functional state of blood-brain barrier mechanisms in the fetus is an important biological phenomenon with implications for normal brain development. It is also important for clinicians to have proper evidence on which to advise pregnant women who may need to take medications for serious medical conditions. Beliefs in immaturity of the blood-brain barrier have held the field back for decades. Their history illustrates the importance of taking account of all the evidence and assessing its quality, rather than selecting papers that supports a preconceived notion or intuitive belief. This review attempts to right the wrongs. Based on careful translation of original papers, some published a century ago, as well as providing discussion of studies claiming to show barrier immaturity, we hope that readers will have evidence on which to base their own conclusions.

[Pregnancy and substance use in France: a literature review]

OBJECTIVES

Substance use during pregnancy is an important public health issue. It requires identifying at-risk populations and risk perception among women.

MATERIALS AND METHODS

A literature review was conducted. It included French studies conducted since 2000 on substance use during pregnancy (tobacco, alcohol, marijuana, psychotropic drugs) and risk perception.

RESULTS

In France, in 2010, 24% of pregnant women smoke--17% in the 3rd trimester. Depending on studies, the prevalence of alcohol use ranged from 12 to 63% and binge drinking ranged from 1 to 7%; daily drinking was below 0.5%. Marijuana use ranged from 1 to 3%, and psychotropic drugs ranged from 2 to 4%. Little research has been dedicated to risk perception. Studies show a lack of awareness about the equivalence of risks between fermented and distilled beverages and about the risks of moderate smoking during pregnancy.

CONCLUSION

Data is lacking to characterize at-risk populations and mechanisms underlying risky behaviors.

Development of an automated imaging pipeline for the analysis of the zebrafish larval kidney

The analysis of kidney malformation caused by environmental influences during nephrogenesis or by hereditary nephropathies requires animal models allowing the in vivo observation of developmental processes. The zebrafish has emerged as a useful model system for the analysis of vertebrate organ development and function, and it is suitable for the identification of organotoxic or disease-modulating compounds on a larger scale. However, to fully exploit its potential in high content screening applications, dedicated protocols are required allowing the consistent visualization of inner organs such as the embryonic kidney. To this end, we developed a high content screening compatible pipeline for the automated imaging of standardized views of the developing pronephros in zebrafish larvae. Using a custom designed tool, cavities were generated in agarose coated microtiter plates allowing for accurate positioning and orientation of zebrafish larvae. This enabled the subsequent automated acquisition of stable and consistent dorsal views of pronephric kidneys. The established pipeline was applied in a pilot screen for the analysis of the impact of potentially nephrotoxic drugs on zebrafish pronephros development in the Tg(wt1b:EGFP) transgenic line in which the developing pronephros is highlighted by GFP expression. The consistent image data that was acquired allowed for quantification of gross morphological pronephric phenotypes, revealing concentration dependent effects of several compounds on nephrogenesis. In addition, applicability of the imaging pipeline was further confirmed in a morpholino based model for cilia-associated human genetic disorders associated with different intraflagellar transport genes. The developed tools and pipeline can be used to study various aspects in zebrafish kidney research, and can be readily adapted for the analysis of other organ systems.

A simplified PBPK modeling approach for prediction of pharmacokinetics of four primarily renally excreted and CYP3A metabolized compounds during pregnancy

During pregnancy, a drug's pharmacokinetics may be altered and hence anticipation of potential systemic exposure changes is highly desirable. Physiologically based pharmacokinetics (PBPK) models have recently been used to influence clinical trial design or to facilitate regulatory interactions. Ideally, whole-body PBPK models can be used to predict a drug's systemic exposure in pregnant women based on major physiological changes which can impact drug clearance (i.e., in the kidney and liver) and distribution (i.e., adipose and fetoplacental unit). We described a simple and readily implementable multitissue/organ whole-body PBPK model with key pregnancy-related physiological parameters to characterize the PK of reference drugs (metformin, digoxin, midazolam, and emtricitabine) in pregnant women compared with the PK in nonpregnant or postpartum (PP) women. Physiological data related to changes in maternal body weight, tissue volume, cardiac output, renal function, blood flows, and cytochrome P450 activity were collected from the literature and incorporated into the structural PBPK model that describes HV or PP women PK data. Subsequently, the changes in exposure (area under the curve (AUC) and maximum concentration (C max)) in pregnant women were simulated. Model-simulated PK profiles were overall in agreement with observed data. The prediction fold error for C max and AUC ratio (pregnant vs. nonpregnant) was less than 1.3-fold, indicating that the pregnant PBPK model is useful. The utilization of this simplified model in drug development may aid in designing clinical studies to identify potential exposure changes in pregnant women a priori for compounds which are mainly eliminated renally or metabolized by CYP3A4.

Prevalence and predictors of over-the-counter medication use among pregnant women: a cross-sectional study in the Netherlands

Background

Over-the-counter-medication (OTC-medication) use during pregnancy can be potentially harmful for the fetus. To successfully counsel the patient it is important to know if the patient is at risk. In this study possible predictors for OTC-medication use were identified and a model was designed to predict OTC-medication use during pregnancy.

Methods

We performed a post-hoc analysis on data collected for a clustered clinical trial to study a screening strategy for Query fever. Pregnant women under supervision of a midwife were eligible for inclusion. These women filled out questionnaires during their pregnancy and post-partum. These questionnaires were used to determine the prevalence and to select possible predictors for OTC-medication use. These predictors were included in a prediction model using multivariate analysis. The discrimination and calibration of the model were assessed with Receiver Operating Characteristic analysis and the Hosmer and Lemeshow test.

Results

Of the 1348 women enrolling in the clustered clinical trial, we included 1246 women in this analysis. The prevalence of OTC-medication use was 12.5%. The predictors for OTC-medication use in our cohort were: nulliparity, use of prescription medication, the presence of a comorbidity, Body Mass Index between 26 and 30 kg/m² and General Practitioner visits. These predictors were used to design a prediction model for OTC-medication use. The area under the Receiver Operating Characteristic-curve of the prediction model was 0.667 (95% CI 0.620-0.714 P<0.001) and the predictive probabilities ranged from 6.6% to 57.4%. The Hosmer and Lemeshow goodness-of-fit test indicated good calibration of the model (P = 0.640).

Conclusion

It is possible to indicate women at risk for OTC-medication use during pregnancy, using five maternal characteristics that independently contribute to the prediction model. The predictors are easy to estimate and the model is easy to implement in daily practice.

Drug use before and during pregnancy in Serbia

BACKGROUND

Observation of drug use patterns during pregnancy is necessary for the recognition of potential bad practices and improvement of safe drug use in pregnancy.

OBJECTIVE

To investigate prescription and over the counter drug use among Serbian women in the 6 months before pregnancy and in the first 6 months of pregnancy, and to evaluate the drugs used according to the risk to a fetus. Setting Six maternity care units and five community pharmacies.

METHOD

A multi-center study was performed in Serbia during the period from March 2009-March 2010. A self-reporting questionnaire was used as a data source. Food and Drug Administration (FDA) risk classification system was used to determine the risk of used drugs for the fetus. Differences between subgroups were assessed using McNemar's test on paired proportions. Main outcome measure Proportion of women exposed to drugs or class of drugs.

RESULTS

The overall drug exposure was higher in pregnancy (34.7 %) than before pregnancy (29.9 %), p > 0.05, in the cohort of 311 pregnant women. A significantly greater prescription drug use, 19.0 versus 27.3 % of women, p < 0.05, and less selfmedication with over the counter drugs in pregnancy, 15.1 versus 8.7 %, p < 0.05, were observed. Commonly used drugs were musculoskeletal drugs, analgesics/antipyretics and respiratory system drugs before pregnancy (13.8, 12.5, and 6.4 % of women, respectively), and progestogens, analgesics/antipyretics, and antibiotics for the systemic use in pregnancy (9.0, 7.7, and 7.4 %, respectively). A greater exposure to drugs belonging to the FDA risk category A (3.9 vs. 60.8 %, p < 0.05), B (18.0 vs. 19.6 %, p > 0.05), C (10.0 vs. 10.3 %, p > 0.05) and D (2.9 vs. 10.9 %, p < 0.05), as well as less exposure to drugs belonging to category X (0.3 vs. 0 %, p > 0.05) were observed in pregnancy. Folic acid was used by 60.8 % of women in pregnancy, and by only 3.9 % before pregnancy.

CONCLUSION

Besides higher overall drug use in pregnancy than before pregnancy, particularly the use of progestogens, and, subsequently, D category drugs, less selfmedication with over the counter drugs was observed in pregnancy. Insufficient use of folic acid before pregnancy requires public health service activities.

Drug exposure during the periconceptional period: a study of 1793 women

BACKGROUND

Many studies have described the prescribing of drugs to pregnant women, but only very few have data concerning the periconceptional period specifically.

AIM

The aim of the study was to evaluate the incidence of exposure to teratogenic drugs during early pregnancy and to determine whether a safer drug exists.

METHODS

In a French health insurances database, we analyzed drugs prescribed during the period starting 1 month before and ending 2 months after the beginning of pregnancy between 1 January 2006 and 31 December 2007. Based on the Summary of Product Characteristics (SPC), drugs we considered were those 'contraindicated', 'not recommended', 'to be avoided', and 'possible' for use during the first trimester of pregnancy. For drugs 'contraindicated', we established if there were alternatives with similar efficacy for the mother and lower risk for the fetus.

RESULTS

Over a period of 2.25 years, 8754 drugs were prescribed to 1793 women starting 1 month prior to and ending 2 months after conception. Among these drugs, 20 (0.2%) were 'contraindicated', 195 (2.2%) were 'not recommended', and 1209 (13.8%) were 'to be avoided' during the first trimester of pregnancy. Twenty (1.1%) women received at least one drug that was 'contraindicated' during the first trimester, 171 (9.5%) received a drug that was 'not recommended' and 768 (42.8%) received a drug that was 'to be avoided'. At least one possible alternative was available for all except one 'contraindicated' drug.

CONCLUSIONS

During the highest teratogenic risk period, 1.1% of women received a contraindicated drug, despite existence of a safer alternative drug. This may be partly accounted for by physicians not being aware of the pregnancy at the time the drug was administered and could be reduced by adding a section entitled 'women of child-bearing potential' to the SPC.

Clinical research enrolling pregnant women: a workshop summary

Clinical research investigates mechanisms of human disease, interventions, or new technologies, but pregnant women are often excluded from clinical studies. Few studies, beyond research on pregnancy, are designed to address questions relevant to pregnant women. A recent National Institutes of Health workshop considered the barriers and opportunities in conducting clinical research studies enrolling pregnant women.

Drugs dispensed in primary care during pregnancy: a record-linkage analysis in Tayside, Scotland

BACKGROUND

For many regularly used drugs, evidence for safe use in pregnancy has not been established. Despite this, international studies have identified high levels of drug prescribing among pregnant women.

OBJECTIVE

To investigate the patterns of prescribing of drugs to women who gave birth in Tayside, Scotland, in 2007.

METHODS

Scottish maternity records were linked to dispensed prescribing data for all women who gave birth in Tayside in 2007. Drugs prescribed were coded according to the US FDA classification for risks of drugs in pregnancy. Patterns of prescribing were investigated during the 3 trimesters of pregnancy and the 3 months prior to conception.

RESULTS

Prescribing in pregnancy was common, with 21 093 prescriptions dispensed to 3356 (85.2%) of the 3937 women. The most frequently prescribed drugs were antacids, antibacterials, oral iron, folic acid preparations and analgesics. Category A drugs (positive evidence of safety in pregnancy) and Category B drugs (some evidence of safety in pregnancy) accounted for 19.6% and 26.9% of all prescriptions dispensed, respectively. Prescribing of Category X drugs (evidence of risk to the fetus; use contraindicated in women who are or may become pregnant) during pregnancy was rare, with 112 prescriptions dispensed to 68 women (1.7%). Most of these were oral contraceptives or sex hormones. Prescribing of Category X drugs fell markedly during the first trimester and remained very low thereafter. Category D drugs (evidence of risk to the fetus but benefits of therapy may outweigh the potential risk) [432] were dispensed to 166 women (4.2%) during pregnancy. The most commonly prescribed Category D drugs were anxiolytics, nicotine replacement therapy and antiepileptic drugs. The frequency of prescribing of Category D drugs reduced in the third trimester. Prescribing of Category C drugs (insufficient evidence to know whether they are harmful) was common. Thirty percent of women received a total of 3641 Category C prescriptions, which accounted for 17.3% of all prescriptions issued during pregnancy. Prescribing of Category C drugs showed only a very modest decline during pregnancy. No FDA code was available for 4035 prescriptions issued (87 different items), the majority of which were for antacids and preparations for indigestion. More than 40% of women received such medications.

CONCLUSIONS

Prescribing of drugs during pregnancy was very common, but the levels of prescribing of drugs that are known to be harmful were low. Much of the prescribing was for drugs related to the pregnancy. While this study provides some evidence that primary-care prescribers in Tayside are prescribing potentially harmful drugs appropriately and with caution during pregnancy, safety data during pregnancy are unavailable for many drugs that are commonly prescribed.

Pattern of drug use during the first trimester among Chinese women: data from a population-based cohort study

AIM

To describe the pattern of drug use among Chinese women during the first trimester and to examine the impact of maternal diseases on the choice of drugs.

METHOD

This drug utilisation study of pregnant women was performed using data from the ABCD cohort study. A total of 4,290 women were enrolled in the analysis. Information was collected by self-completion questionnaire combined with the "Maternal health handbook".

RESULTS

Of the 4,290 women interviewed, 75.9% of women took at least one drug during the first trimester. Users took a mean number of 1.43 drugs. The most frequently used drugs were folic acid (65.2%), vitamins (14.6%), calcium (12.0%), minerals (11.1%), Chinese traditional patent medicine (CTPM; 10.1%) and anti-infectives (6.5%). Among the women having used CTPM, influenza/cold and threatened abortion were the most commonly reported indications. Logistic regression analysis of drug use (excluding nutritional and haematological drugs) shows that CTPM and Western medicine are both associated with the use of drugs for occasional diseases and against threatened abortion. Maternal chronic diseases were not associated with the use of CTPM.

CONCLUSION

This analysis of pregnant women showed that drugs were prescribed to most women, even when nutritional and haematological drugs were excluded. Our data reflect, except for drugs used for chronic diseases, a general reluctance among Chinese women to use Western medicine and resorting to CTPM during pregnancy.

Amoxicillin and amoxicillin plus clavulanate: a safety review

Despite the considerable number of newer antibacterials made available over the past decades, amoxicillin, alone or in combination with clavulanic acid, still accounts among the most widely used antibacterial agents. Although they are often considered 'twin drugs', they are different both in terms of antibacterial activities and of safety profile. It is well documented that the clavulanate component may cause adverse reactions by itself, thus exposing patients to further, and sometimes undue, risks. Although amoxicillin/clavulanate should be considered as an alternative agent only for the treatment of resistant bacteria, evidence shows that it is often used also when a narrow-spectrum antibiotic would have been just as effective. This prescription habit may have serious consequences in terms of patients' safety, as well as in terms of the development of bacterial resistance.

Methodologies for improving response rates in surveys of physicians: a systematic review

Although physician surveys are an important tool in health services and policy research, they are often characterized by low response rates. The authors conducted a systematic review of 66 published reports of efforts to improve response rates to physician surveys. Two general strategies were explored in this literature: incentive and design-based approaches. Even small financial incentives were found to be effective in improving physician response. Token nonmonetary incentives were much less effective. In terms of design strategies, postal and telephone strategies have generally been more successful than have fax or Web-based approaches, with evidence also supporting use of mixed-mode surveys in this population. In addition, use of first-class stamps on return envelopes and questionnaires designed to be brief, personalized, and endorsed by legitimizing professional associations were also more likely to be successful. Researchers should continue to implement design strategies that have been documented to improve the survey response of physicians.

Extent of medication use in breastfeeding women

BACKGROUND

The types of and extent to which medications are used by breastfeeding women have not been thoroughly investigated in the United States. The relationship between medication use during pregnancy and lactation has also been insufficiently investigated.

METHODS

A survey was given to a cohort of women who delivered their babies at a single center. The participants were asked to record the medications they had taken during pregnancy and subsequently were contacted each month during lactation to determine what medications they had taken.

RESULTS

Breastfeeding women took significantly more medications per month than pregnant women (p < 0.0001). Women who were breastfeeding also took prescription medications more frequently than women who were pregnant (p < 0.0001). The number of medications taken per month showed no trend throughout the course of breastfeeding. The medications most often used by breastfeeding women were multivitamins, nonsteroidal anti-inflammatory drugs, acetaminophen, progestins, antimicrobials, and decongestants. Over a third of the subjects took medications rated possibly or probably unsafe, or had unknown safety.

CONCLUSION

The women in this study took more prescription and nonprescription medications while breastfeeding than they did during pregnancy. Many of the medications taken have unknown safety for the breastfed infant. The results of this study should direct further research toward determining the safety of medications commonly used during lactation and to promote the labeling of these medications.

Medications during pregnancy: antihypertensives and immunosuppressives

Use of prescription and nonprescription medications is common during pregnancy and is required in many women with underlying kidney disease or hypertension and in all with solid-organ allografts. Systematic assessment of drug safety during pregnancy is lacking, as are rigorous and comprehensive studies of pharmacokinetics and pharmacodynamics to guide drug selection and dosing across pregnancy. Renal and hepatic clearances of many drugs change markedly during pregnancy and pitfalls may complicate routine therapeutic monitoring of some drugs during pregnancy. However, available data and clinical experience allow reasonable strategies for selection and dosing of immunosuppressive agents in pregnant transplant recipients and of antihypertensive agents in women with mild or more severe hypertension complicating their pregnancies.

Drug utilization and teratogenicity risk categories during pregnancy

A limited number of studies have investigated in detail the use of drugs during pregnancy. Researchers in the present study investigated the details of drug utilization in pregnant women during the month before pregnancy, at the time that they became aware of the pregnancy, and during the first trimester. Face-to-face interviews were conducted with 359 pregnant women who were admitted to the fetal medicine unit at a university hospital for diagnosis and follow-up. A questionnaire was used to document sociodemographic characteristics and details of drug use. Drugs were categorized according to the US Food and Drug Administration fetal risk classification. Mean maternal age was 29.9+/-5.1 y, and mean gestational age was 19.6+/-9.5 wk. Many of the pregnant women studied (46.6%) were university graduates, and most (61.9%) had a relatively high annual income. Mean gestational age when participants first learned of their pregnancy was 39.8+/-16.4 d. One hundred seventeen participants (32.6%) used drugs during the month before conception, 54 (15%) at the time when they learned of their pregnancy, 180 (50.1%) at the time of the interview, and 289 (80.5%) during the first trimester. The percentages of drugs in categories D and X used by these subjects were 14%, 13.5%, 2.9%, and 5.9%, respectively. Most of the drugs were hormones. The total rate of drug utilization was not high before and during the first trimester of pregnancy. A considerable number of women were using drugs from the D and X categories; however, these numbers decreased significantly when women learned of their pregnancies. Intake of folic acid, vitamins, and iron was very low during the preconception period and was not high enough during the first trimester; this suggests that particular attention should be paid to the use of beneficial "safe" drugs during the preconception and early pregnancy periods.

The potential of the European network of congenital anomaly registers (EUROCAT) for drug safety surveillance: a descriptive study

BACKGROUND

European Surveillance of Congenital Anomalies (EUROCAT) is a network of population-based congenital anomaly registries in Europe surveying more than 1 million births per year, or 25% of the births in the European Union. This paper describes the potential of the EUROCAT collaboration for pharmacoepidemiology and drug safety surveillance.

METHODS

The 34 full members and 6 associate members of the EUROCAT network were sent a questionnaire about their data sources on drug exposure and on drug coding. Available data on drug exposure during the first trimester available in the central EUROCAT database for the years 1996-2000 was summarised for 15 out of 25 responding full members.

RESULTS

Of the 40 registries, 29 returned questionnaires (25 full and 4 associate members). Four of these registries do not collect data on maternal drug use. Of the full members, 15 registries use the EUROCAT drug code, 4 use the international ATC drug code, 3 registries use another coding system and 7 use a combination of these coding systems. Obstetric records are the most frequently used sources of drug information for the registries, followed by interviews with the mother. Only one registry uses pharmacy data. Percentages of cases with drug exposure (excluding vitamins/minerals) varied from 4.4% to 26.0% among different registries. The categories of drugs recorded varied widely between registries.

CONCLUSIONS

Practices vary widely between registries regarding recording drug exposure information. EUROCAT has the potential to be an effective collaborative framework to contribute to post-marketing drug surveillance in relation to teratogenic effects, but work is needed to implement ATC drug coding more widely, and to diversify the sources of information used to determine drug exposure in each registry.

National patterns of medication use during pregnancy

PURPOSE

To describe patterns of medication use during pregnancy in ambulatory care settings according to the U.S. Food and Drug Administration (FDA) pregnancy risk classification.

METHODS

A cross-sectional study of two national ambulatory care surveys, sampling all office visits made by pregnant women in 1999 and 2000, was conducted. Using the FDA pregnancy risk classification, patterns of medication use and predictive factors for FDA pregnancy risk D or X (D/X) medications were evaluated.

RESULTS

In 1999 and 2000, about half of all pregnant visits had one or more medications. Among the total visits, FDA Class A was the majority (private = 65.7%; hospital = 79.5%; p < 0.05) followed by Class C (private = 26.5%; hospital = 36.4%; p < 0.05). Class D/X medications accounted for 6.4% and 2.9% of visits in private and hospital, respectively (p < 0.05). Medications with unknown pregnancy categories were predominant in the private setting (12.0% and 3.9%; p < 0.05). Age, insurance type, region, physician specialty, and number of medications were associated with a category D/X prescription. Among hospital visits, those from the West region and with private insurance were more likely to receive category D/X prescriptions. Number of medications was strongly associated with high-risk drugs in both settings.

CONCLUSIONS

This study shows considerable medication use among pregnant women. The prevalence of visits with FDA pregnancy category D/X drugs was moderate, but still indicates exposure to high-risk medications.

Antibiotics in pregnancy: analysis of potential risks and determinants in a large German statutory sickness fund population

PURPOSE

Antibiotics are frequently prescribed drugs in pregnancy. The purpose of the study was to analyse the use, the potential risks and the determinants of systemic antibiotic prescriptions during pregnancy.

METHODS

A large, nation-wide acting German statutory sickness fund provided prescription data and personal data of 41,293 pregnant women. For this study, all prescriptions of systemic antibiotics (ATC: J01) dispensed to each woman during a 21-month period were analysed. We used the FDA risk classification system and enrolled a literature search to identify potentially harmful antibiotics. To investigate the impact of geographical and socio-economic determinants in antibiotic prescribing, a multivariate logistic regression model was performed.

RESULTS

Of the 41,293 women, 19.7% received at least one antibiotic drug during pregnancy. There was a shift to relatively safe and reduced antibiotic drug use during pregnancy. Prescribing of contraindicated antibactericals or potentially harmful drugs was seen in 521 women (1.3% of all women). In the logistic regression, being younger than 21 years (adjusted OR 2.14, 95%CI 1.80-2.53) or being welfare recipient (adjusted OR 1.57, CI 1.25-2.00) was strongly associated with higher antibiotic use. Significantly lower antibiotic use was seen in 5 of 16 German federal states (OR 0.74-0.83).

CONCLUSIONS

About 20% of pregnant women received antibiotics, and 1.3% received a harmful drug. To minimise the risks, detailed guidelines are needed for the antibiotic treatment during pregnancy.

First-trimester exposure to amoxycillin/clavulanic acid: a prospective, controlled study

AIMS

The number of published studies on the use of amoxycillin/clavulanic acid during pregnancy is small and so is the number of pregnancies investigated in those studies. In this study we wished to investigate prospectively the safety of intrauterine exposure to amoxycillin/clavulanic acid in a relatively large cohort of women.

METHODS

Women treated (n = 191) with amoxycillin/clavulanic acid during the first trimester of pregnancy were recruited from two teratogen information centres in Israel. Exposed women were matched for age, smoking habits and alcohol consumption with 191 controls exposed to amoxycillin only for similar medical indications.

RESULTS

Maternal age, birth weight, gestational age at delivery, rates of live births and abortions were comparable between the two groups. Rates of major malformations in the amoxycillin/clavulanic acid group (3/158, 1.9%) did not differ significantly from controls (5/163, 3%) (P = 0.49, relative risk = 0.62, 95% confidence interval 0.15, 2.55), and were within the expected baseline risk for the general population.

CONCLUSION

These data suggest that exposure to amoxycillin/clavulanic acid during pregnancy is unlikely to be associated with an increased risk of malformations.

Drug prescription in pregnancy: analysis of a large statutory sickness fund population

OBJECTIVE

To examine the prescription of drugs in Germany prior to, during and after pregnancy.

METHODS

For the first time, prescription data of a large cohort of pregnant women, from a German statutory sickness fund, were available for scientific analysis. For each woman who gave birth between June 2000 and May 2001 reimbursed prescriptions for two periods (90 days each) before pregnancy, three during and two after delivery were considered. The drugs were classified according to the ATC code.

RESULTS

Of the 41,293 women, 96.4% received at least one drug during pregnancy. A median of 7 drugs per women was prescribed. Excluding vitamins, minerals, iodide and iron, 85.2% received at least one drug and the median was 3. Magnesium, which was seldom prescribed outside of pregnancy, was by far the most frequently prescribed substance (20% of all prescriptions, 61% of the women). Iron (54% of the women) and iodide (31%) were also prescribed often. The prescription rates of gynaecological antiinfectives (maximum in third trimester: 23% of the women), antacids (max. in third trim.: 11%), as well as antiemetics and antinauseants (max. in first trim.: 8%) during pregnancy considerably increased. A decrease was seen for analgesics, antiinflammatory and antirheumatic drugs, muscle relaxants, ophtalmologicals and anti-acne preparations, for example. Potential teratogenic drugs were prescribed to 1.3% of the women.

CONCLUSION

This analysis of a large nation-wide cohort of pregnant women showed that during pregnancy drugs were prescribed to most women, even when vitamins, minerals, iodide and iron were omitted. Magnesium and iron seemed to have been over-prescribed. On the other hand, the official recommendation for iodide substitution, to prevent thyroid diseases in mother and child, was insufficiently implemented. In our opinion, regular analysis of prescription data can identify potential harmful therapies and focal points where guidelines are needed and can check their implementation.

Drug use by pregnant women and comparable non-pregnant women in The Netherlands with reference to the Australian classification system

OBJECTIVE

To describe drug use in pregnancy, and compare drug use of pregnant women with non-pregnant women with respect to possible teratogenicity.

STUDY DESIGN

A cross-sectional study based on pharmacy records from 1997 to 2001 was performed. Pregnant women and matched non-pregnant women (same physician and age) were identified. Prescriptions were set against the Australian risk classification.

RESULTS

Thirty-five percent of all prescriptions for non-pregnant women were safe in pregnancy (Australian classification A), in 14% the risk was unknown (B1, B2), 49% were potentially harmful drugs (B3, C, D, X), and in 3% no classification was available. For pregnant women these figures were 86, 3, 10 and 2%, respectively. In non-pregnant women the highest percentages of prescriptions for unsafe drugs were for psycholeptics (99% not classified as safe), psychoanaleptics (100%), anti-inflammatory/antirheumetic products (100%), antihistamines (94%), antacids/anti-ulcer drugs (81%), antiepileptics (100%), beta-blockers (100%), systemic antimycotics (100%), antiprotozoals (97%), diuretics (100%) and immunosuppressives (100%). In pregnant women this pattern was comparable, except for antihistamines (22%) and antacids/anti-ulcer drugs (3%).

CONCLUSION

We conclude that many drugs used by non-pregnant women should be avoided in pregnancy, and that pregnant women indeed do so. However, for some drug groups the available safe alternatives are limited.

Medication use during pregnancy: data from the Avon Longitudinal Study of Parents and Children

OBJECTIVE

To present data on the self-reported use of all types of medicinal products collected during pregnancy in a large cohort in southwest England.

METHODS

Pregnant women with a delivery date during 1991-1992 and forming part of the prospective, population-based Avon Longitudinal Study of Parents and Children (ALSPAC) were sent up to four self-completion postal questionnaires during pregnancy. Text data collected from the questions on drug usage were coded using an ALSPAC drug dictionary based on the World Health Organization Drug Dictionary.

RESULTS

At least one antenatal self-completion questionnaire was completed for 14,119 pregnancies, and 11,545 women completed all four. The data included prescription, over-the-counter, herbal and homeopathic products as well as iron, vitamins and other supplements. Only 7.6% did not report use of any medicinal product throughout their entire pregnancy. The remaining 92.4% used at least one product at some stage. After exclusion of iron, folate, vitamins, supplements, herbal and homeopathic products and skin emollients, 83% of those completing all questionnaires had used conventional therapeutic drugs. Analgesics were reported by approximately one-third of women at each stage during pregnancy, and paracetamol was the most frequently reported substance. Iron preparations were reported by 33% of the full cohort, at some stage, and folate by 21.9%. Use of anti-anaemic products increased during pregnancy with the greatest incidence at 32 weeks. Other vitamins and supplements were taken by 17.4% at some stage. Use of vitamins decreased throughout pregnancy from 9.6% in early pregnancy to 5% at 32 weeks. Antacids were reported by 23% at 32 weeks. The reported incidence of antibiotic use decreased slightly during pregnancy from 8% early on to 5.8% at 32 weeks; amoxicillin was the most frequently reported antibacterial.

CONCLUSION

Use of medicinal products was high during pregnancy in the ALSPAC cohort. This finding is consistent with data from recent publications.

Pregnancy Exposure Registries

Scientifically valid data on the safety of drug use during pregnancy are a significant public health need. Data are rarely available on the fetal effects of in utero exposure in human pregnancies, particularly when a drug is first marketed. Data from animal reproductive toxicology studies, which function as a screen for potential human teratogenicity, are usually all that is available in a product's labelling. For practising clinicians, translating known animal risks into an accurate assessment of teratogenic risks in their patients is very difficult, if not impossible. Without human data on the effects of in utero drug exposure, it is difficult for physicians and other healthcare providers (e.g. genetic counsellors) to adequately counsel patients about fetal risks. Therefore, a pregnant woman may decide to unnecessarily terminate a wanted pregnancy or forego needed drug therapy. In spite of the lack of data on the safety of drug use during human pregnancies, pregnant women are exposed to drugs either as prescribed therapy or inadvertently before pregnancy is known (over one-half of pregnancies are unplanned). Because little is known about the teratogenic potential of a drug in humans before marketing, post-marketing surveillance of drug use in pregnancy is critical to the detection of drug-induced fetal effects. The existing passive mechanism of spontaneous reporting of adverse drug effects is inadequate to routinely detect drug-induced fetal risks or lack of such risks. Therefore, post-marketing pregnancy exposure registries are being increasingly used to proactively monitor for major fetal effects and to describe margins of safety associated with drug exposure during pregnancy. However, differing methodological rigour has been applied to the development of pregnancy exposure registries. It is important that all pregnancy registries develop epidemiologically sound written study protocols a priori. It is only through the use of rigorous methodology and procedures that data from pregnancy exposure registries will withstand scientific scrutiny. Successful recruitment of an adequate number of exposed pregnancies, aggressive follow-up, and complete and accurate ascertainment of pregnancy outcome are critical attributes of a well-designed registry.

Prescription of Hazardous Drugs During Pregnancy

BACKGROUND

Prescribing drugs to pregnant women requires the balancing of benefits and risks. Only a small proportion of drugs are known to be harmful to the fetus, but for the vast majority of drugs little evidence of fetal safety exists.

AIM

To determine the prescription pattern of potentially and clearly harmful prescription drugs during pregnancy with reference to drug safety categorisation, and to define the drug groups primarily responsible for multiple drug use during pregnancy.

STUDY DESIGN

A retrospective, register-based cohort study.

METHODS

Linkage of three nationwide registers in Finland. Data collection included prescription drugs purchased during the preconception period and each trimester in the pregnant cohort, and the corresponding time periods in the non-pregnant controls. The pregnancy safety categorisation was determined for each drug (Anatomic Therapeutic Chemical [ATC] code) by using the Swedish classification of approved medicinal products (Farmaceutiska Specialiteter i Sverige [FASS]) and if not available, the corresponding Australian (Australian Drug Evaluation Committee [ADEC]) or US categorisation (FDA). GROUPS STUDIED: Women applying for maternity support (maternal grants) during the year 1999 (n = 43 470) plus non-pregnant control women matched by age and hospital district (n = 43 470).

RESULTS

In the pregnant cohort, 20.4% of women purchased at least one drug classified as potentially harmful during pregnancy, and 3.4% purchased at least one drug classified as clearly harmful. A significant decline occurred in the number of pregnant women purchasing potentially and clearly harmful drugs during the first trimester when compared with the preconception period, and the decline continued from the first to the second trimester. In the pregnant cohort, 107 (0.2%) women purchased at least ten different drugs during pregnancy. The drugs most commonly purchased in this group were topical corticosteroids and nasal preparations.

CONCLUSION

The use of hazardous prescription drugs declines during pregnancy but prescriptions of known teratogens and the relatively frequent practice of polypharmacy in epilepsy place emphasis on the need for careful pre-pregnancy counselling. However, drug safety classifications give a very crude estimation of risk and should only be used as general guidelines when planning treatment. Risk assessment must always be made on an individual basis, and pregnant women with illnesses requiring treatment must be treated adequately.

Prescription drugs during pregnancy and lactation--a Finnish register-based study

OBJECTIVE

To examine the use of prescription drugs in Finnish women before and during pregnancy and lactation.

METHODS

A register-based study linking four nation-wide registers in Finland: the Maternal Grants Register, the Drug Prescription Register, and the Special Refund Register (all maintained by the Social Insurance Institution in Finland; KELA), and the Finnish Population Register. The study included all women applying for maternity support (maternal grants) during the year 1999, and non-pregnant control women matched by age and hospital district. Data collection included the number and type of prescription drugs purchased by the two cohorts during preconception (3 months before pregnancy), each trimester, and lactation.

RESULTS

Of the 43,470 pregnant women, 46.2% purchased at least one drug and 12.7% three or more different drugs during pregnancy. Corresponding proportions for the control cohort were 55.2% (OR 0.7, 95% CI 0.6-0.7) and 23.0% (OR 0.5, 95% CI 0.5-0.5). The drugs most frequently purchased during pregnancy were systemic antibiotics (24.1% of pregnant women vs 27.3% controls; OR 0.8, 95% CI 0.8-0.9) and gynaecological anti-infective agents (8.3% vs 1.5%; OR 5.5, 95% CI 5.5-6.5). For pregnant women, purchases of most drug groups had already declined during the first trimester, but no reduction was apparent in drugs for chronic illnesses (epilepsy, asthma, diabetes).

CONCLUSIONS

Although drugs were purchased abundantly during pregnancy, a significant decline occurred for most drug groups. The medication pattern for chronic illnesses remained unchanged. The purchase of several different drugs was relatively common and raises concerns.

First trimester exposure to cefuroxime: a prospective cohort study

AIMS

There are no published studies on the safety of cefuroxime use during pregnancy. We therefore investigated prospectively the possible teratogenic effect of intrauterine exposure to cefuroxime.

METHODS

One hundred and six women who received cefuroxime during the first trimester of pregnancy were recruited from three teratogen information centres in Israel. Exposed women were paired for age, smoking habits and alcohol consumption with references being exposed to nonteratogenic antibiotics administered for the same indications.

RESULTS

Maternal history, birthweight, gestational age at delivery, rates of live births, spontaneous abortions and fetal distress were comparable among the two groups. Rates of major malformations in the cefuroxime group (3.2%) did not differ from references (2%) (P = 0. 61, relative risk = 1.56, 95% confidence interval 0.27-9.15). There was a significantly higher rate of induced abortions among the cefuroxime exposed women as compared to the references (P = 0.04, relative risk = 3.33, 95% confidence interval 0.94-11.77).

CONCLUSIONS

Our data may suggest that exposure to cefuroxime during the first trimester is probably not associated with an increased risk for malformations or spontaneous abortions; however, in light of the small sample size and the broad confidence limits, larger studies are needed to confirm these findings.