Drugs to avoid in pregnancy

Drugs given in pregnancy can adversely affect the fetus in many ways. Anxiety about birth defects is a major parental concern during pregnancy. Doctors and their patients often seek information about the potential teratogenicity of drugs that are taken by or prescribed for the pregnant woman. Because no drug is entirely without side effects, great caution should be taken when prescribing in pregnancy. The development of knowledge in understanding the use of drugs during pregnancy has been in stalemate in comparison to other areas of therapeutics, mainly due to difficulties in testing new products in pregnant women and paucity of good quality research. In this article, we aim to review current knowledge of the epidemiology of drug use among pregnant women, drug metabolism in pregnancy, adverse fetal and neonatal effects of drugs and specific effects of drugs that are relatively or absolutely contraindicated in pregnancy.     

Drugs in pregnancy. Drugs to avoid.

Drugs given in pregnancy can adversely affect the fetus in many ways. Anxiety about birth defects is a major parental concern during pregnancy. Doctors, midwives and their patients often seek information about the potential teratogenicity of drugs that are taken by, or prescribed for, the pregnant woman. Because no drug is entirely without side-effects, great caution should be taken when prescribing in pregnancy. The development of knowledge in understanding the use of drugs during pregnancy has been in stalemate in comparison to other areas of therapeutics, due mainly to difficulties in testing new products in pregnant women and lack of good quality research. In this chapter, we review current knowledge of the epidemiology of drug use among pregnant women, drug metabolism in pregnancy, adverse fetal and neonatal effects of drugs and specific effects of drugs that are relatively or absolutely contraindicated in pregnancy.     

Prenatal behavioral risk screening by computer in a health maintenance organization-based prenatal care clinic

Cigarette smoking, alcohol and drug abuse, and stressful life events are significant contributors to prematurity and low birth weight in the United States. Identification and treatment of pregnant women with these risk factors require obtaining complete and accurate psychosocial histories. The purpose of this study was to determine whether a computer interview developed by our staff is appropriate for assessing behavioral risk factors for adverse pregnancy outcomes and for educating pregnant women about healthy behaviors during pregnancy. This computer interview asks about pregnant patients' perceived life stressors, diet, use of cigarettes and alcohol, and abuse of drugs. The study population consisted of 201 medically insured Hispanic and non-Hispanic white women attending a health maintenance organization--based prenatal clinic. Almost all subjects rated the computer interview favorably. Medical record reviews were conducted to compare participants' reports of cigarette, alcohol, and drug use obtained from paper-and-pencil interviews with behaviors reported during the computer interview. Although self-reported rates of smoking did not differ between the two interview techniques, a much higher percentage of women reported alcohol and drug use during the computer interview. Study participants scored significantly higher on a test measuring knowledge of the effects of stress, diet, and substances of abuse on pregnancy than did a control group. Results demonstrated the potential value of computer-interactive software programs for assessing high-risk behaviors among pregnant women in this population and educating them about healthy behaviors during pregnancy.     

Pharmacotherapy for pregnant women with addictions

OBJECTIVE: Dependence on alcohol, nicotine, or illicit drugs during pregnancy continues to be a problem of major medical, social, and fetal consequences. The purpose of this systematic review was to summarize current experience that pertains to pharmacotherapy for pregnant women with specific chemical addictions. STUDY DESIGN: Studies were identified through Medline and HealthSTAR (1979-2003) that linked specific pharmacotherapy with pregnancy. This article reviews the English language literature for clinical studies that link the 2 conditions. In addition, reference lists of all articles that were obtained were evaluated for other potential citations. RESULTS: Pregnant women are excluded systematically from almost all drug trials. Most knowledge about the fetal effects from maternal substance and medication use comes from animal data and from case reports and small clinical series. With the exception of methadone and nicotine replacement, clinical experience with antiaddictive medications in pregnant women is either very limited (alcohol, stimulants) or nonexistent (cannabis, hallucinogens). CONCLUSION: Antiaddiction medications are important in the treatment of pregnant women with opioid and nicotine dependence and are of growing importance in the treatment of alcohol and stimulant dependence. Future directions will be toward increasing knowledge about current drug therapy and in developing new antiaddiction medications.     

Drug intake behaviour of immigrants during pregnancy

OBJECTIVE: To assess differences between native Spanish and immigrant pregnant women in behaviour relating to the use of medications during pregnancy. STUDY DESIGN: This cross-sectional study was carried out at the department of obstetrics and gynaecology of an acute-care teaching hospital in the city of Barcelona, Spain. A total of 1103 women who gave birth at the hospital during a 1-year period were enrolled in the study. Each woman was interviewed by a gynaecologist during her stay in hospital after delivery, with special reference to drug use during the pregnancy. Drug exposure was assigned to trimesters, and drugs were divided into therapeutic groups, while the women taking part were divided up by nationality, educational level, parity and age. Data were analysed using bivariate, multivariate, and cluster analyses. RESULTS: Slightly over half (55.7%) of the women were native to Spain and 44.3% were immigrants of other nationalities. About a quarter, or 25.4%, of pregnant patients had not taken any drugs during their pregnancies. The most frequent drugs taken by the others were vitamins, which were used mostly by Spanish women, followed by analgesics, which were mostly taken by non-Spanish western women. The largest group who had taken folic acid was made up of non-Spanish western women, while the Asiatic patients had taken this in the smallest proportion of cases. CONCLUSIONS: Spanish patients and immigrants from other western countries showed a similar behaviour in terms of drug intake during pregnancy, which was different from the behavioural patterns seen in pregnant patients from developing countries.     

Pregnancy-related substance use in the United States during 1996-1998

OBJECTIVE: To provide a baseline estimate of the national prevalence of pregnancy-related illicit drug use and abstinence rates. METHODS: We analyzed data collected between 1996 and 1998 from the National Household Survey on Drug Abuse, a nationally representative sample survey of 22,303 noninstitutionalized women aged 18-44 years, of whom 1,249 were pregnant. RESULTS: During 1996-1998, 6.4% of nonpregnant women of childbearing age and 2.8% of pregnant women reported that they used illicit drugs. Of the women who used drugs, the relative proportion of women who abstained from illicit drugs after recognition of pregnancy increased from 28% during the first trimester of pregnancy to 93% by the third trimester. However, because of postpregnancy relapse, the net pregnancy-related reduction in illicit drug use at postpartum was only 24%. Marijuana accounted for three-fourths of illicit drug use, and cocaine accounted for one-tenth of illicit drug use. Of those who used illicit drugs, over half of pregnant and two-thirds of nonpregnant women also used cigarettes and alcohol. Among the sociodemographic subgroups, pregnant and nonpregnant women who were young (18-30 years) or unmarried, and pregnant women with less than high school education had the highest rates of illicit drug use. CONCLUSION: The continued burden of illicit drug use during pregnancy calls for policy efforts to enable primary care providers to identify and refer women who use substances to treatment and support services. Prevention of uptake of illicit drug use should be an integral part of public health programs for young women.     

Inflammatory bowel disease: management issues during pregnancy

Introduction Inflammatory bowel disease often affects women during their reproductive years, causing management concerns for obstetricians caring for these patients during pregnancy. Treatment Apart from methotrexate, most drugs used regularly to treat ulcerative colitis and Crohn's disease can safely be used by pregnant women. No causal relationship has been established between exposure to sulfasalazine or other 5-aminosalicylic acid drugs and the development of congenital malformations and these drugs may be used with relative safety during pregnancy and lactation. Current evidence indicates that maternal use of azathioprine and mercaptopurine is not associated with an increased risk of congenital malformations, though impaired foetal immunity, intrauterine growth retardation and prematurity are occasionally observed. Cyclosporin is not teratogenic, but may be associated with growth retardation and prematurity. Conclusions Pregnancy should be avoided in women treated with methotrexate because of its known abortifacient effects and risk of causing typical malformations. There is no actual evidence of adverse effect in pregnant women receiving Infliximab but the amount of clinical information is small. The treatment with metronidazole or ciprofloxacin for short durations appear to be safe, but there is no data about the effects of increased length of treatment as required in Crohn's disease remains unknown. Control of disease activity before conception and during pregnancy is critical to optimise both maternal and foetal health. A multidisciplined approach involving both obstetrician and gastroenterologist and education about pregnancy are essential components of the treatment of any young women with IBD.     

Risk of drug-induced congenital defects

Defects attributable to drug therapy represent about 1% of congenital defects of known aetiology. This means that a precautionary attitude and correct use of drugs in fertile, and especially pregnant, women is a feasible form of prevention. Drugs currently in use with proven teratogenic effect number approximately 25, but new pharmaceutical drugs are constantly in preparation. Recognition of a drug-induced teratogenic effect is a complex procedure taking into account not only experimental animal data but also experience in humans. Considering that 40% of pregnancies are not planned, it follows that any drug with known or suspected teratogenic potential must be used only under strict medical control. Also, adequate knowledge on potential teratogenicity of a drug permits modification of therapy before conception. It goes without saying that any drug should be used during pregnancy only if it is essential, and it would be prudent to use only those where adequate information is provided and prior clinical experience is available. Teratology Information Services can assist both physicians and patients when any doubt exists.     

Basic obstetric pharmacology

Pregnancy is associated with a variety of physiological changes that can alter the pharmacokinetics and pharmacodynamics of several drugs. However, limited data exists on the pharmacokinetics and pharmacodynamics of the majority of the medications used in pregnancy. In this article, we first describe basic concepts (drug absorption, bioavailability, distribution, metabolism, elimination, and transport) in pharmacokinetics. Then, we discuss several physiological changes that occur during pregnancy that theoretically affect absorption, distribution, metabolism, and elimination. Further, we provide a brief review of the literature on the clinical pharmacokinetic studies performed in pregnant women in recent years. In general, pregnancy increases the clearance of several drugs and correspondingly decreases drug exposure during pregnancy. Based on current drug exposure measurements during pregnancy, alterations in the dose or dosing regimen of certain drugs are essential during pregnancy. More pharmacological studies in pregnant women are needed to optimize drug therapy in pregnancy.     

Screening for substance use in pregnancy: a practical approach for the primary care physician

Our goal was to identify risk factors for substance use during pregnancy for primary care physicians so that we could assess a woman's risk of alcohol or illicit drug use. Participants were 2002 Medicaid-eligible pregnant women with < or =2 visits to prenatal care clinics in South Carolina and Washington State. Structured interviews were used to collect data. Logistic regressions and classification and regression trees identified predictors for pregnant women at high risk for substance use. Approximately 9% of the sample reported current use of either drugs or alcohol or both. Past use of alcohol or cigarettes, including during the month before pregnancy, most differentiated current drug or alcohol users from current nonusers. Our analysis suggests that primary care physicians can ask 3 questions in the context of a prenatal health evaluation to target women for referral to a full clinical assessment for drug and alcohol use.     

Unprescribed Drug Products and Pregnancy

A significant number and variety of drugs are consumed by individuals today, including women of childbearing age. There are potentially harmful fetal effects of drugs consumed during pregnancy; therefore, there is need for discussion and investigation of the problem of drug consumption during pregnancy. A study which verified the use of unprescribed drugs before and during pregnancy by a group of postpartum women and identified the sources of information regarding drug usage and purchase of them was undertaken. The study also illustrated the need to incorporate information about the use of unprescribed drugs during pregnancy into a preconceptional and antepartal program of education. Recommendations for further research and clinical activities are offered.     

Medication Safety During Pregnancy: Improving Evidence‐Based Practice

Nearly 90% of women in the United States have taken medications during pregnancy. Medication exposures during pregnancy can result in adverse pregnancy and neonatal outcomes including birth defects, fetal loss, intrauterine growth restriction, prematurity, and longer‐term neurodevelopmental outcomes. Advising pregnant women about the safety of medication use during pregnancy is complicated by a lack of data necessary to engage the woman in an informed discussion. Routinely, health care providers turn to the package insert, yet this information can be incomplete and can be based entirely on animal studies. Often, adequate safety data are not available. In a busy clinical setting, health care providers need to be able to quickly locate the most up‐to‐date information in order to counsel pregnant women concerned about medication exposure. Deciding where to locate the best available information is difficult, particularly when the needed information does not exist. Pregnancy registries are initiated to obtain more data about the safety of specific medication exposures during pregnancy; however, these studies are slow to produce meaningful information, and when they do, the information may not be readily available in a published form. Health care providers have valuable data in their everyday practice that can expand the knowledge base about medication safety during pregnancy. This review aims to discuss the limitations of the package insert regarding medication safety during pregnancy, highlight additional resources available to health care providers to inform practice, and communicate the importance of pregnancy registries for expanding knowledge about medication safety during pregnancy.     

Methadone treatment during pregnancy

OBJECTIVE: To review the literature on methadone use by pregnant women. DATA SOURCES: A search was conducted on CINAHL, MEDLINE, and PSYCHINFO under "pregnancy" and "methadone." STUDY SELECTION: Articles published between 1988-1998 were reviewed and chosen based upon relevance to the objective. DATA EXTRACTION: Data were extracted and organized under the following headings: effects of methadone on pregnancy outcome, management of the pregnant woman on methadone, and implications of social and political policies for pregnant women who use opiates. DATA SYNTHESIS: Methadone treatment is most effective for pregnant women who receive care in a comprehensive service center. Few systematic investigations exist concerning methadone maintenance during pregnancy, thus no formal guidelines for management exist. Changes in federal policies for drug treatment and welfare regulations will challenge health care professionals who provide treatment for opiate-dependent pregnant women. CONCLUSIONS: Treatment with methadone is the standard of care for the opiate-using pregnant woman, despite findings challenging its benefits and efficacy in women who continue to use illicit drugs.     

Visceral leishmaniasis (kala-azar) and pregnancy

OBJECTIVE: The aim of the present review was to close the gap in the approach to pregnant women with visceral leishmaniasis (kala-azar) by providing up-to-date information to obstetricians about physiopathology, epidemiology, vertical transmission, drugs and treatment during pregnancy. BACKGROUND: Infection with Leishmania chagasi during pregnancy is rare and deserves special attention since little information is available regarding the occurrence of visceral leishmaniasis during gestational period and the real possibility of vertical transmission of this disease. Because specific areas in the world are endemic for the disease and considering the continuous growth of the population, cases of pregnant women with visceral leishmaniasis are becoming more frequent. Unfortunately, textbooks on infectious diseases do not include this specific group of patients, and studies in the literature on aspects related to pregnancy and visceral leishmaniasis are scarce. CONCLUSIONS: Vertical transmission of leishmaniasis is possible and the institution of treatment is imperative in cases of pregnant women with kala-azar. Amphotericin B is strongly recommended as the first choice drug due to its fewer maternal-fetal adverse effects.     

Pregnant Women’s Knowledge of Influenza and the Use and Safety of the Influenza Vaccine During Pregnancy

IntroductionWe wished to assess pregnant women’s knowledge of influenza, vaccine safety during pregnancy and breast feeding, and the recommendations for use of the influenza vaccine in pregnancy.MethodsWe performed a cross-sectional survey of postpartum women during influenza season in 2006.ResultsPregnant women’s overall knowledge of these subjects was poor. Most women (95%) knew that influenza is highly contagious, but almost 90% incorrectly believed that pregnant women have the same risk of complications as non-pregnant women. Only one half of the women were aware of national recommendations for vaccination during pregnancy and that the vaccine is safe during pregnancy and breast feeding, and 80% incorrectly believed that the vaccine can cause birth defects. Only 20% of women had been offered the vaccine during the current pregnancy or a prior pregnancy.ConclusionsPregnant women’s knowledge about influenza vaccine recommendations and safety during pregnancy is poor. There is substantial room for improvement among prenatal care providers in both patient education and offering the vaccine.     

Obtaining drug exposure histories during pregnancy.

One hundred fifty-three pregnant patients were included in this study to verify the amount of drugs ingested during their pregnancies. The results demonstrate that, unknown to the physician, pregnant patients take a variety of pharmacologic agents. The patient's medical record is considered grossly inadequate in documenting an accurate assessment of a patient's exposure to drugs taken during pregnancy. Drug histories were obtained utilizing the hospital pharmacist drug history interview and home diary. Validity testing of the pharmacist's drug history and of the medical record history was not performed. The patient's compliance for utilizing the home diary for drugs or chemicals taken during their pregnancy was 83% (127 patients). It was shown that the usual methods of drug history documentation will identify only 30% of the actual drug exposure to the fetus.     

ACOG Committee Opinion No. 354: Treatment with selective serotonin reuptake inhibitors during pregnancy

Depression is a common condition among women of reproductive age, and selective serotonin reuptake inhibitors (SSRIs) are frequently used for the treatment of depression. However, recent reports regarding SSRI use during pregnancy have raised concerns about fetal cardiac defects, newborn persistent pulmonary hypertension, and other negative effects. The potential risks associated with SSRI use throughout pregnancy must be considered in the context of the risk of relapse of depression if maintenance treatment is discontinued. The American College of Obstetricians and Gynecologists' Committee on Obstetric Practice recommends that treatment with all SSRIs or selective norepinephrine reuptake inhibitors or both during pregnancy be individualized and paroxetine use among pregnant women or women planning to become pregnant be avoided, if possible.     

Anticoagulants

Pregnancy is a period of heightened coagulability and enhanced risk for thrombotic complications. Thromboembolism is the leading cause of maternal mortality. Anticoagulants are very useful during pregnancy for the acute treatment of venous thromboembolism and for the prevention of recurrent venous thromboembolism. They may also be beneficial in patients with thrombophilias, particularly among women who have experienced adverse pregnancy outcomes such as recurrent pregnancy loss. Anticoagulation is essential but problematic in the management of pregnant women with mechanical heart valve prostheses. When utilizing these medications among pregnant women the potential benefits must be balanced against the possibility of maternal haemorrhagic complications, adverse effects on the pregnancy or toxic effects on the fetus. This chapter summarizes current knowledge about the anticoagulant agents, their potential toxicities and their therapeutic role in pregnant women with various indications for anticoagulant therapy.     

Patterns of medication use during and prior to pregnancy: the MAP study

We interviewed 140 pregnant women of any gestational age attending antenatal clinics at the Women's and Children's Hospital in Adelaide during September-October 1999 to elicit information about their patterns of medication use during and in the 3 months prior to their current pregnancy. Demographic information, information on women's prescribed, non-prescribed, and non-medicinal drug use during and in the 3 months prior to pregnancy, and information about both their general sources of information on medication use and their specific reasons for medication uptake/cessation during pregnancy were obtained. The women used an average of 0.7 0.8 prescribed and 2.3-2.6 non-prescribed medications (total 3.1-3.3) in the 3 pregnancy trimesters, compared with 1.0 prescribed and 2.2 non-prescribed prior to pregnancy. Use of a prescribed or non-prescribed medication was 96-97% across trimesters. Simple analgesics, vitamin/mineral supplements, and antacids were the most commonly taken medications. Antibiotics were the most commonly prescribed medication. Use of class A medications increased during pregnancy while use of non-class A medications decreased. Peri-conceptional folate supplementation was 31%. Alcohol consumption and cigarette smoking decreased after diagnosis of pregnancy. Both prescribed and non-prescribed medication use is common during all trimesters of pregnancy. However, overall use changes little compared with pre-pregnancy values. Rates of peri-conceptional folate supplementation are low.