Medications in the first trimester of pregnancy: Most common exposures and critical gaps in understanding fetal risk
ABSTRACT To determine which medications are most commonly used by women in the first trimester of pregnancy and identify the critical gaps in information about fetal risk for those medications.
Self-reported first-trimester medication use was assessed among women delivering liveborn infants without birth defects and serving as control mothers in two large case-control studies of major birth defects. The Teratology Information System (TERIS) expert Advisory Board ratings of quality and quantity of data available to assess fetal risk were reviewed to identify information gaps.
Responses from 5381 mothers identified 54 different medication components used in the first trimester by at least 0.5% of pregnant women, including 31 prescription and 23 over-the-counter medications. The most commonly used prescription medication components reported were progestins from oral contraceptives, amoxicillin, progesterone, albuterol, promethazine, and estrogenic compounds. The most commonly used over-the-counter medication components reported were acetaminophen, ibuprofen, docusate, pseudoephedrine, aspirin, and naproxen. Among the 54 most commonly used medications, only two had "Good to Excellent" data available to assess teratogenic risk in humans, based on the TERIS review.
For most medications commonly used in pregnancy, there are insufficient data available to characterize the fetal risk fully, limiting the opportunity for informed clinical decisions about the best management of acute and chronic disorders during pregnancy. Future research efforts should be directed at these critical knowledge gaps. Copyright © 2013 John Wiley & Sons, Ltd.
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ABSTRACT: What are the dispensing rates of drugs suspected to be associated with teratogenic mechanisms among pregnant Dutch women? In a substantial proportion of pregnancies in our study population at least one drug associated with a teratogenic mechanism was dispensed in the first trimester of pregnancy. The main teratogenic mechanisms of medical drugs that may affect fetal development in the first trimester of pregnancy have been described previously. However, information on the dispensing rate of such drugs among women at all stages of pregnancy is lacking. To determine how often medications suspected to be associated with a teratogenic mechanism are used by pregnant women, we studied 32 016 pregnancies included in the IADB.nl database between 1998 and 2009. We estimated dispensing rates of medical drugs suspected to be associated with teratogenic mechanisms in our study population. The IADB.nl database includes all pharmacy dispensings for an estimated population of 220 000 in 1994-1998 and c.500 000 since 1999. In addition, trends in first trimester dispensing rates over time and patterns of receiving multiple drugs associated with teratogenic mechanisms were evaluated. In addition, we determined the number of pregnancies in which multiple prescription drugs from one or more teratogenic categories were dispensed in the first trimester, and we evaluated the numbers of different medications dispensed that could be grouped within a specific teratogenic mechanism. In 175 per 1000 pregnancies [95% confidence interval (CI), 171-179] at least one drug associated with a teratogenic mechanism was dispensed in the first trimester. The total dispensing rate was 236 per 1000 pregnancies (95% CI 232-241) in the 3 months before pregnancy and an increasing trend was seen in the second [214 per 1000 (95% CI 209-218)] and third [327 per 1000 (95% CI 322-332)] trimesters. The first trimester dispensing rates increased between 1998 and 2009 for selective serotonin-reuptake inhibitors (P < 0.001) and serotonin receptor agonists/antagonists (P < 0.001). In 71.8% of pregnancies in which drugs associated with teratogenic mechanisms were dispensed in the first trimester, women received drugs related to only one mechanism. Of the pregnancies in which drugs from multiple teratogenic categories were dispensed in the first trimester, 1148 (72.6%) women received drugs from 2 categories, 317 (20.0%) from three categories, 88 (5.6%) from 4 categories, 28 (1.8%) from 5 categories and 1 from 6 categories. Several women received multiple prescription medications grouped within a single teratogenic mechanism in the first trimester, ranging between 13.3% for cyclo-oxygenase inhibitors and 41.8% for serotonin receptor agonists/antagonists. We used a dispensing database, therefore actual use of the medication prescribed is unknown and non-compliance could have led to overestimation of exposure prevalences. Owing to the uncertainties concerning the safety of medication use during pregnancy, the results of this study stress the need for cautious prescription of medication associated with teratogenic mechanisms to women of reproductive age. This is further supported by our finding that women received multiple prescription medications grouped within a single teratogenic mechanism in the first trimester, which would theoretically increase strongly the risk of birth defects. Marleen van Gelder was supported by the Netherlands Organisation for Scientific Research/NWO (grant no. 021.001.008). No competing interests are declared. TRIAL REGISTRATION NUMBER: N/A.Human Reproduction 10/2013; 29(1). DOI:10.1093/humrep/det369 · 4.57 Impact Factor
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ABSTRACT: What is the current state of knowledge on the human risks of drugs suspected to be associated with teratogenic mechanisms? Evidence for the presence or absence of human risks of birth defects is scarce or non-existent for the majority of drugs associated with teratogenic mechanisms. Medical drugs suspected to be associated with teratogenic mechanisms are dispensed to a significant proportion of women in the first trimester of pregnancy. However, an overview of the current state of knowledge on the human teratogenic effects of these drugs is lacking. We performed an extensive literature review of studies in the English language which examined the associations between selected drugs and specific birth defects. The literature was identified from MEDLINE and EMBASE from database inception (January 1946 and January 1974, respectively) through December 2012 using 287 terms for the drugs of interest. We only included studies if they specified birth defect subtypes and, specifically for cohort studies, involved live born infants. Of 14 406 potentially relevant articles, 556 full-text articles were assessed for eligibility and 250 met the inclusion criteria. The studies included were divided into four categories according to their design to increase the validity of our study. Epidemiologic studies assessing teratogenic risks were identified for less than half of the drugs included in the review. A substantial variation in study design and data collection methods was observed. When the data collection method is of questionable validity, study quality may be affected considerably. For only 15 drugs of interest, birth defects were assessed in at least 1000 infants in cohort studies, and 13 of these were associated with one or more specific birth defects. The majority of associations observed in case-control studies are as yet unconfirmed. For most drugs and drug groups, however, the numbers of exposed infants studied were too small to draw any conclusions regarding their human teratogenic risks. The validity of our review is limited by the validity and reporting of the studies from which the data were extracted. Some relevant studies might have been missed owing to the exclusion of articles not in the English language and publication bias. It is a cause of concern that the drugs most often dispensed in the first trimester of pregnancy are not necessarily the drugs for which teratogenic risks have been studied. Future studies should focus on those drugs that are most commonly used during pregnancy and for which the teratogenic risks are unknown, such as iron preparations, serotonin receptor agonists or antagonists, drugs used in fertility treatment, dihydrofolate reductase inhibitors. Marleen van Gelder was supported by the Netherlands Organisation for Scientific Research/NWO (grant no. 021.001.008). No competing interests are declared. TRIAL REGISTRATION NUMBER: N/A.Human Reproduction 10/2013; 29(1). DOI:10.1093/humrep/det370 · 4.57 Impact Factor
- 11/2013; 1(6):675-6. DOI:10.1016/j.jaip.2013.08.005