The teratogenesis risk associated with antiseizure medication duotherapy in women with epilepsy.

PURPOSE: To investigate rates of occurrence of pregnancies associated with a foetal malformation (FM pregnancy rates) following simultaneous intrauterine exposure to two antiseizure medications in 524 pregnancies in women with epilepsy from the Australian Pregnancy Register who were treated simultaneously with various combinations and dosages of two antiseizure medications (duotherapy). RESULTS: FM pregnancy rates tended to be higher in those exposed simultaneously to two antiseizure medications, each of which was a statistically significant teratogen (valproate, topiramate, or carbamazepine), than when there was exposure to only one such teratogen. When there was exposure to only one such teratogen together with clonazepam or levetiracetam, for neither of which there was statistically significant evidence of heightened teratogenicity, the FM pregnancy rates also tended to be higher, but less so. When lamotrigine was the other component of the duotherapy with an established teratogen, FM pregnancy rates tended to be lower than that for the teratogen used as monotherapy. CONCLUSION: Leaving aside issues in relation to seizure control, our data suggest that it would be best to avoid using established teratogenic antiseizure medications (carbamazepine, valproate and topiramate) in combination with each other due to the increased FM risks. When combining an established teratogenic medication with a less teratogenic one, i.e. lamotrigine, levetiracetam or clonazepam, lamotrigine appears to be the safer option.

Use of isotretinoin among girls and women of childbearing age and occurrence of isotretinoin-exposed pregnancies in Germany: A population-based study.

BACKGROUND: Exposure to isotretinoin during pregnancy must be avoided due to its teratogenicity, but real-world data on its use are scarce. We aimed to describe (i) isotretinoin use in women of childbearing age in Germany; (ii) the occurrence of isotretinoin-exposed pregnancies; and (iii) malformations among children exposed in utero. METHODS AND FINDINGS: Using observational data from the German Pharmacoepidemiological Research Database (GePaRD, claims data from approximately 20% of the German population), we conducted annual cross-sectional analyses to determine age-standardized prevalence of isotretinoin use between 2004 and 2019 among girls and women aged 13 to 49 years. In cohort analyses, we estimated the number of exposed pregnancies by assessing whether there was prescription supply overlapping the beginning of pregnancy (estimated supply was varied in sensitivity analyses) or a dispensation within the first 8 weeks of pregnancy. Data of live-born children classified as exposed in a critical period according to these criteria were reviewed to assess the presence of congenital malformations. The age-standardized prevalence of isotretinoin use per 1,000 girls and women increased from 1.20 (95% confidence interval [CI]: 1.16, 1.24) in 2004 to 1.96 (95% CI: 1.92, 2.01) in 2019. In the base case analysis, we identified 178 pregnancies exposed to isotretinoin, with the number per year doubling during the study period, and at least 45% of exposed pregnancies ended in an induced abortion. In sensitivity analyses, the number of exposed pregnancies ranged between 172 and 375. Among live-born children, 6 had major congenital malformations. The main limitation of this study was the lack of information on the prescribed dose, i.e., the supply had to be estimated based on the dispensed amount of isotretinoin. CONCLUSIONS: Isotretinoin use among girls and women of childbearing age increased in Germany between 2004 and 2019, and there was a considerable number of pregnancies likely exposed to isotretinoin in a critical period. This highlights the importance of monitoring compliance with the existing risk minimization measures for isotretinoin in Germany.

Face-to-face: isotretinoin use and pregnancy outcome.

Isotretinoin has been used to treat severe acne for more than 40 years. There are no accurate data on the absolute risk of potential teratogenicity to all fetuses exposed to isotretinoin. According to current guidelines, isotretinoin should be discontinued at least 1 month before pregnancy. This study enrolled pregnant women who contacted the Clinical Pharmacology and Toxicology Unit for individual drug risk assessment between 2016 and 2020. Data on maternal characteristics and isotretinoin exposures were obtained at first consultation. After delivery, follow-up calls were conducted using a structured questionnaire. Of 2,323 pregnant women consulted, 1.3% (31/2,323) had systemic isotretinoin exposure during and before pregnancy. Of 31 prospectively followed pregnancies, eight terminated electively. Most elective terminations (7/8) were performed because of the fear of fetal malformation. The majority of continued pregnancies (16/23) resulted in healthy live birth. There were no major birth defects. In six pregnancies, intrauterine deaths (three first trimester, three second trimester) were reported. Cesarean section was performed in 70.5% (12/17) of all deliveries. The median gestational age at birth was 39, and no preterm births were reported. Local isotretinoin treatments in six cases were evaluated and presented additionally, and all babies were born healthy. Based on the results of this study, there was no evidence of major birth defect, mental disorder, or retinoid embryopathy associated with the use of isotretinoin in pregnancy. Not local use, but systemic exposure to isotretinoin is of great concern that results in pregnancy termination.

A new perspective on isotretinoin in pregnancy: Pregnancy outcomes, evaluation of complex phenotypes, and importance of teratological counselling.

OBJECTIVES: Teratogens are responsible for 5% of all known causes of congenital anomalies. Isotretinoin, a retinoic acid-derived agent, leads to congenital anomalies in 21-52% of cases when exposure occurs during pregnancy according to studies conducted before 2006. However, rates of congenital anomalies were much lower in later studies. The purpose of this study was to investigate the rates of congenital anomalies in isotretinoin exposure during pregnancy, isotretinoin exposure before pregnancy, and a control group unexposed to any teratogenic agents. STUDY DESIGN: In this cohort study, we divided pregnant women admitted to our center between 2009 and 2020 into two groups: isotretinoin exposure before and during the pregnancy (n = 77) and isotretinoin exposure before the pregnancy (n = 75). We selected the control group from among the non-teratogen exposed pregnant women with a simple random sampling method. Obstetricians calculated the ages of all pregnancies via ultrasound (USG) (crown-rump diameter for the first trimester; biparietal diameter and femur length for the second trimester). After birth, a pediatric genetics specialist examined all babies. Whole-exome sequencing (WES) was conducted on the babies who displayed complex phenotypes. RESULTS: Among the isotretinoin exposure before and during the pregnancy, isotretinoin exposure before the pregnancy, and the control groups, there were statistically significant differences in live births (respectively, 64.3 %, 88 %, 93.3 %), congenital anomalies (respectively, 28.6 %, 6.1 %, 1.4 %), miscarriages (respectively, 13 %, 2.7 %, 4 %), terminations (respectively, 32.5 %, 9.3 %, 2.7 %), and premature births (11.9 %, 16.7 %, 2.9 %) (respectively, p < 0.001, p < 0.001, p = 0.014, p < 0.001). We detected novel phenotypical features in five patients. CONCLUSIONS: Our study demonstrated that study design, long-term follow-up, teratological counseling, and implementation of advanced molecular analysis in complex phenotypes with novel phenotypical features are beneficial for understanding the association of congenital anomalies with isotretinoin exposure. While evaluating congenital anomalies, we detected statistically significant differences between isotretinoin exposure before and during the pregnancy vs control, but we did not detect any statistically significant differences between isotretinoin exposure before the pregnancy and controls. Another finding of the study is that WES might be an efficient way to evaluate complex phenotypes in isotretinoin-exposed babies; however, further research is required.

Use of Acitretin Among Girls and Women of Childbearing Age and Occurrence of Acitretin-Exposed Pregnancies in Germany.

BACKGROUND AND OBJECTIVE: Acitretin has long-lasting teratogenic properties. Therefore, pregnancies must be avoided during and within 3 years after acitretin treatment. We aimed to describe (i) acitretin use in women of childbearing age in Germany, (ii) the occurrence of acitretin-exposed pregnancies, and (iii) malformations among children exposed in utero. METHODS: Using 2004-2019 data from the German Pharmacoepidemiological Research Database (GePaRD-claims data from ~ 20% of the German population), we determined annual age-standardized prevalence of acitretin use among girls and women aged 13-49 years. In longitudinal analyses, we estimated the number of exposed pregnancies by assessing whether the exposure window assigned to the last dispensation before pregnancy (days covered by dispensation plus 3 years) overlapped the onset of pregnancy or whether there was a dispensation in the first eight weeks of pregnancy. Data of live-born children with in utero exposure to acitretin were reviewed to assess the presence of congenital malformations. RESULTS: The age-standardized prevalence of acitretin use per 1000 girls and women was 0.04 in 2019. We identified 35 acitretin-exposed pregnancies; 94.3% of these pregnancies were classified as exposed because they occurred within 3 years after stopping acitretin treatment. Among 18 live-born children linked to their mother, four children (22.2%) had congenital malformations (three children with a major malformation). CONCLUSIONS: We observed 35 acitretin-exposed pregnancies mainly because treatment ended too late before pregnancy. Approximately one in five children born from these pregnancies had malformations, highlighting the importance of drawing more attention to the long-lasting teratogenicity of this drug.

Congenital malformations and preeclampsia associated with integrase inhibitor use in pregnancy: A single-center analysis.

BACKGROUND: Antiretroviral therapy (ART) decreases perinatal HIV transmission, but concerns exist regarding maternal and infant safety. We compared the incidence of congenital malformations and other adverse outcomes in pregnancies exposed to integrase inhibitor (INSTI) versus non-INSTI ART. SETTING: Single-site review of all pregnancies among women living with HIV between 2008 and 2018. METHODS: We used binomial family generalized estimating equations to model the relationship of congenital anomalies and pregnancy outcomes with exposure to INSTI or dolutegravir (DTG) versus non-INSTI ART. RESULTS: Among 257 pregnancies, 77 women received ≥1 INSTI (54 DTG, 14 elvitegravir, 15 raltegravir), 167 received non-INSTI, and 3 had missing data. Fifty congenital anomalies were identified in 36 infants. Infants with first-trimester DTG or any first-trimester INSTI exposure had higher odds of congenital anomalies than infants with first-trimester non-INSTI exposure (OR = 2.55; 95%CI = 1.07-6.10; OR = 2.61; 95%CI = 1.15-5.94, respectively). Infants with INSTI exposure after the second trimester had no increased odds of anomalies. Women with INSTI exposure had higher odds of preeclampsia (OR = 4.73; 95%CI = 1.70-13.19). Among women who received INSTI, grade ≥3 laboratory abnormalities were noted in 2.6% while receiving the INSTI and 3.9% while not receiving the INSTI, versus 16.2% in women who received non-INSTI. There was no association between INSTI exposure and other pregnancy outcomes. CONCLUSION: In our cohort, first-trimester INSTI exposure was associated with increased rates of congenital anomalies and use of INSTI during pregnancy was associated with preeclampsia. These findings underscore the need for continued monitoring of the safety of INSTI in pregnancy.

Metformin Versus Insulin and Risk of Major Congenital Malformations in Pregnancies With Type 2 Diabetes: A Nordic Register-Based Cohort Study.

OBJECTIVE: To assess the risk of major congenital malformations with metformin versus insulin in pregnancies with type 2 diabetes. RESEARCH DESIGN AND METHODS: This cohort study used four Nordic countries' nationwide registers of live and stillborn infants exposed to metformin or insulin during first trimester organogenesis. Main exclusion criteria were type 1 diabetes, polycystic ovary syndrome, fertility treatment, and exposure to other diabetes drugs. Adjusted risk ratios (RRs) and 95% CIs were estimated for any and cardiac malformations. RESULTS: Of 3,734,125 infants in the source population, 25,956 were exposed to metformin or insulin in the first trimester, and 4,023 singleton infants were included. A malformation was diagnosed in 147 (4.7%) of 3,145 infants with exposure to any metformin (alone or in addition to insulin) and 50 (5.7%) of 878 infants with exposure to insulin alone (RR 0.84, 95% CI 0.46-1.54). Among 2,852 infants exposed to metformin alone and 293 infants exposed to metformin in addition to insulin 127 (4.4%) and 20 (6.8%), respectively, had a malformation. The adjusted risk was not increased for either metformin alone (0.83, 0.44-1.58) or both metformin and insulin (0.98, 0.56-1.69) versus insulin alone. Corresponding RRs for cardiac malformations were 1.01 (0.55-1.84) for any metformin, 0.92 (0.47-1.81) for metformin alone, and 1.72 (0.76-3.91) for both metformin and insulin. CONCLUSIONS: No evidence of an increased malformation risk with metformin versus insulin in the first trimester was found. Results should be interpreted with caution since information on glycemic control was missing.

Maternal traditional Chinese medicine exposure and risk of congenital malformations: a multicenter prospective cohort study.

INTRODUCTION: The potential teratogenic risk of traditional Chinese medicine (TCM) is of widespread concern; however, related evidence is largely absent in humans. This study aimed to compare the prevalence of congenital malformations between pregnant women with and without TCM exposure. MATERIAL AND METHODS: This was a multicenter prospective cohort study of 17 713 women who participated in a survey on periconceptional TCM exposure. Primary outcome was congenital malformations diagnosed from a survey conducted on the day 42 after delivery. RESULTS: A total of 16 751 pregnant women with 273 congenital malformations were included in the analysis. Fetuses exposed to TCM had an increased risk of congenital malformations compared to those without exposure (odds ratio [OR] 2.10; 95% confidence interval [CI] 1.09-4.02) after controlling for potential confounders. There were significant associations with congenital malformations in women with early pregnant exposure (OR 2.04, 95% CI 1.00-4.20) and for those who received ≥2 TCM formulas (OR 5.84, 95% CI 1.44-23.65). Pre-pregnancy TCM exposure was significantly associated with an increased risk of congenital heart defects (OR 12.69; 95% CI 3.01-53.51). CONCLUSIONS: Periconceptional TCM exposure is associated with an increased risk of congenital malformation. This effect was cumulative and sensitive to periconceptional age. Therefore, TCM deserves more attention and should be used cautiously for pregnant women and those trying to become pregnant.

Atomoxetine in Early Pregnancy and the Prevalence of Major Congenital Malformations: A Multinational Study.

Objective: Most research on safety of attention-deficit/hyperactivity disorder (ADHD) medications during pregnancy concerns central nervous system stimulants, while little is known about the safety of atomoxetine, a primary treatment alternative. We assessed the prevalence of major congenital malformations overall, and cardiac malformations and limb malformations specifically, after first-trimester exposure.Methods: In this cohort study, we included all approximately 2.4 million pregnancies ending in live births recorded in the population-based nationwide health registers of Denmark, Iceland, Norway, and Sweden (2003-2017) and approximately 1.8 million publicly insured pregnancies ending in live births recorded in the US Medicaid Analytic eXtract (MAX, 2001-2013) health care claims database. We compared the prevalence of major congenital malformations in the newborn among pregnancies exposed and unexposed to atomoxetine. For each country, we calculated prevalence ratios (PRs), crude and stratified by propensity scores (PSs). We pooled the country-specific PS strata to obtain a PR adjusted for potential confounding factors.Results: We identified 368 pregnancies exposed to atomoxetine during the first trimester in the 4 Nordic countries and 622 in the US. The pooled crude PR for any major congenital malformation was 1.18 (95% CI, 0.88-1.60), and the adjusted PR was 0.99 (95% CI, 0.74-1.34). For cardiac malformations, the adjusted PR was 1.34 (95% CI, 0.86-2.09). For limb malformations, the adjusted PR was 0.90 (95% CI, 0.38-2.16).Conclusions: After atomoxetine exposure in early pregnancy, we observed no increase in major congenital malformations overall and, although with some uncertainty due to sample size, no statistically increased risk estimates for cardiac malformations and limb malformations.

The North American Antiepileptic Drug Pregnancy Registry: A Canadian Subgroup Analysis.

BACKGROUND: The North American AED Pregnancy Registry (NAAPR) provides crucial data for understanding the risks of antiepileptic drug (AED) exposure in pregnancy. This study aims to quantify the Canadian contribution to NAAPR and compare AED usage in pregnancy in Canada and the USA. METHODS: Enrollment rate ratios (ERR) to NAAPR, adjusted for the populations of women of childbearing age, were calculated for the USA, Canada, and for the different Canadian provinces. Methods of enrollment to NAAPR and AED usage were compared between the two countries using chi-squared tests. RESULTS: Between 1997 and 2019, 10,215 pregnant women enrolled into NAAPR: 4.1% were Canadian (n = 432, ERR = 0.39, CI95% = 0.35-0.43). Within Canada, no patients were enrolled from the three northern territories or from Prince Edward Island. While fewer patients than expected enrolled from Quebec (ERR = 0.35, CI95% = 0.19-0.58), Nova Scotia had the highest enrollment rate (ERR = 1.55; CI95% = 0.66-3.11). Compared with their American peers, Canadians were less likely to have been enrolled by their healthcare provider and more likely to have been enrolled via social media (p < 0.01). Canadian women were more likely to be taking carbamazepine (24% vs. 15%; p < 0.01) or valproic acid (8% vs. 4%; p < 0.01). CONCLUSION: The proportion of Canadian enrollees into NAAPR was less than expected based on the relative population size of Canadian women of reproductive age. Greater Canadian enrollment to NAAPR would contribute to ongoing worldwide efforts in assessing the risks of AEDs use in pregnant women and help quantify rates of AED usage, major congenital malformations, and access to subspecialized epilepsy care within Canada.

Association of In Utero Antipsychotic Medication Exposure With Risk of Congenital Malformations in Nordic Countries and the US.

Importance: Psychiatric disorders are common among female individuals of reproductive age. While antipsychotic medication use is increasing, the safety of such medications in pregnancy is an area with large evidence gaps. Objective: To evaluate the risk of first-trimester antipsychotic exposure with respect to congenital malformations, focusing on individual drugs and specific malformation subtypes. Design, Setting, and Participants: This cohort study used data from nationwide health registers from the 5 Nordic countries and the US and spanned 1996 to 2018. The Nordic cohort included all pregnancies resulting in singleton live-born infants, and the US cohort consisted of publicly insured mothers linked to their live-born infants nested in the nationwide Medicaid Analytic eXtract. Data were analyzed from November 2020 to April 2022. Exposures: One or more first-trimester dispensing of any atypical, any typical, and individual antipsychotic drugs. Main Outcomes and Measures: Any major congenital malformation and specific malformation subtypes previously suggested to be associated with antipsychotic exposure in utero: cardiovascular malformations, oral clefts, neural tube defects, hip dysplasia, limb reduction defects, anorectal atresia/stenosis, gastroschisis, hydrocephalus, other specific brain anomalies, and esophageal disorders. Propensity score stratification was used to control for potential confounders. Pooled adjusted estimates were calculated using indirect standardization. Results: A total of 6 455 324 unexposed mothers (mean maternal age range across countries: 24-31 years), 21 751 mothers exposed to atypical antipsychotic drugs (mean age range, 26-31 years), and 6371 mothers exposed to typical antipsychotic drugs (mean age range, 27-32 years) were included in the study cohort. Prevalence of any major malformation was 2.7% (95% CI, 2.7%-2.8%) in unexposed infants, 4.3% (95% CI, 4.1%-4.6%) in infants with atypical antipsychotic drug exposure, and 3.1% (95% CI, 2.7%-3.5%) in infants with typical antipsychotic drug exposure in utero. Among the most prevalent exposure-outcome combinations, adjusted relative risks (aRR) were generally close to the null. One exception was olanzapine exposure and oral cleft (aRR, 2.1 [95% CI, 1.1-4.3]); however, estimates varied across sensitivity analyses. Among moderately prevalent combinations, increased risks were observed for gastroschisis and other specific brain anomalies after atypical antipsychotic exposure (aRR, 1.5 [95% CI, 0.8-2.6] and 1.9 [95% CI, 1.1-3.0]) and for cardiac malformations after chlorprothixene exposure (aRR, 1.6 [95% CI, 1.0-2.7]). While the association direction was consistent across sensitivity analyses, confidence intervals were wide, prohibiting firm conclusions. Conclusions and Relevance: In this study, considering the evidence from primary and sensitivity analyses and inevitable statistical noise for very rare exposure-outcome combinations, in utero antipsychotic exposure generally was not meaningfully associated with an increased risk of malformations. The observed increased risks of oral clefts associated with olanzapine, gastroschisis, and other specific brain anomalies with atypical antipsychotics and cardiac malformations with chlorprothixene requires confirmation as evidence continues to accumulate.

Exposure to selective noradrenalin reuptake inhibitors during the first trimester of pregnancy and risk of congenital malformations: A meta-analysis of cohort studies.

Selective serotonin-noradrenalin reuptake inhibitors (SNRIs) are used to treat depression and anxiety during pregnancy; however, information regarding their foetal safety is limited. Cohort studies concerning congenital malformations in infants born to mothers exposed to SNRIs during the first trimester of pregnancy were identified. Eight studies were included in the analysis. In general, the use of SNRIs was not associated with an increased risk of overall congenital malformations when compared with no exposure (rate ratio [RR] = 1.07, 95% confidence interval [CI] = 0.94-1.22; P = 0.31), exposure to SSRIs (RR = 1.12, 95% CI = 0.97-1.31; P = 0.12) and no exposure with clinical indication (RR = 1.04, 95% CI = 0.9-1.2; P = 0.564). A significantly increased risk of cardiac malformations was observed (RR = 1.33, 95% CI = 1.15-1.53; P < 0.001); however, this association was not statistically significant when the reference group comprised mothers exposed to SSRIs (RR = 1.1, 95% CI = 0.85-1.43; P = 0.47) or no exposure with clinical indication (RR = 1.17, 95% CI = 0.95-1.42; P = 0.13). The evidence shows no increased risk of congenital malformations and argues against a substantial cardiac teratogenic effect of SNRIs.

Pregnancy outcomes after first-trimester exposure to buspirone: prospective longitudinal outcomes from the MGH National Pregnancy Registry for Psychiatric Medications.

Buspirone is commonly used to treat anxiety disorders among reproductive-aged women. To date, the reproductive safety of buspirone in humans has been particularly sparse. We sought to provide preliminary data from the Massachusetts General Hospital National Pregnancy Registry for Psychiatric Medications (NPRPM) on the risk of major malformations after first-trimester buspirone exposure. The NPRPM enrolls pregnant women with psychiatric disorders to prospectively assess for major congenital malformations after in utero exposure to psychotropics. Women are interviewed twice during pregnancy and once at 12 weeks postpartum. Data regarding women who took buspirone during the first trimester were extracted from the NPRPM database. Data were assessed as a rigorously ascertained case series to determine the incidence of major malformations among those exposed to buspirone. The primary outcome was obtained by maternal postpartum interview and medical record review. As of January 6, 2022, N = 97 women enrolled in the registry took buspirone during their first trimester. Of these women, 68 were evaluable and eligible for this analysis. Four women had twins, resulting in 72 infants. Among this sample, there were no malformations present. These preliminary data represent the only prospectively ascertained sample of pregnancy outcomes after first-trimester buspirone exposure. Albeit a small sample, no major malformations were observed in this cohort. The rigorous prospective ascertainment of outcomes is a strength of this study. Future analyses are planned that will include larger numbers of women with exposures to buspirone and comparison with control groups matched for demographic and diagnostic variables.

The Use of Antiepileptic Drugs During Pregnancy and Fetal Outcomes.

Epilepsy affects approximately 1 percent of the population and roughly 1 million women of childbearing age. Estimates suggest that 0.3-0.7 percent of pregnancies occur in women with epilepsy. Epilepsy itself increases the risk of congenital malformation and medications add to this risk. Also, approximately one-half of the use of medications for epilepsy are used for other indications, possibly increasing exposure in some women. As controlled trials with these medications are not performed during pregnancy, data has been accumulated primarily through databases and case studies. This review is intended to update the practitioner about the use and concerns of antiepileptic medications in the presnant woman and the potential effects on the fetus and neonate.

Pregnancy Outcomes With Exposure to Second-Generation Antipsychotics During the First Trimester.

Objective: To investigate the risk of major congenital malformations associated with exposure to second-generation antipsychotics (SGAs) in the first trimester.Methods: Pregnant women who received consultation on drug exposure from the Japan Drug Information Institute in Pregnancy from October 2005 to December 2016 were asked to complete a questionnaire at 1 month after the expected delivery date. The questionnaire included items on pregnancy outcome, date of delivery, gestational age at delivery, malformations in the infant that were confirmed by the pediatrician's report, and the following parameters at birth: height, weight, head circumference, and chest circumference. Odds ratios (ORs) for major congenital malformations among live-born children of pregnant women with SGA exposure during the first trimester (SGA group) relative to children of women not exposed to SGAs and medications known to be teratogenic (comparison group) were estimated using an inverse probability of treatment weighting approach.Results: Of 404 women with SGA exposure during the first trimester, there were 351 live births, 3 stillbirths, 34 spontaneous abortions, and 16 elective abortions. The rate of major congenital malformations among live-born children was 0.9% (3/351) in the SGA group and 1.8% (70/3,899) in the comparison group. No statistically significant differences were observed in the adjusted OR for major congenital malformations (adjusted OR = 0.44; 95% CI, 0.12-1.48; P = .179).Conclusions: SGA exposure during the first trimester is not associated with an increased risk of major congenital malformations. These findings might be reassuring for pregnant women who require SGAs.

Genital defects seen in sons of men taking major diabetes drug.

Large study hints that taking metformin before conception could raise risk of birth defects by affecting sperm.

First-trimester exposure to benzodiazepines and risk of congenital malformations in offspring: A population-based cohort study in South Korea.

BACKGROUND: Benzodiazepines are frequently prescribed during pregnancy; however, evidence about possible teratogenicity is equivocal. We aimed to evaluate the association between first-trimester benzodiazepine use and the risk of major congenital malformations. METHODS AND FINDINGS: Using Korea's nationwide healthcare database, we conducted a population-based cohort study of women who gave birth during 2011 to 2018 and their live-born infants. The exposure was defined as one or more benzodiazepine prescriptions during the first trimester. We determined the relative risks (RRs) and confidence intervals (CIs) of overall congenital malformations and 12 types of organ-specific malformations. Infants were followed from birth to death or 31 December 2019, whichever came first (up to 8 years of age). Propensity score fine stratification was employed to control for 45 potential confounders. Among a total of 3,094,227 pregnancies, 40,846 (1.3%) were exposed to benzodiazepines during the first trimester (mean [SD] age, 32.4 [4.1] years). The absolute risk of overall malformations was 65.3 per 1,000 pregnancies exposed to benzodiazepines versus 51.4 per 1,000 unexposed pregnancies. The adjusted RR was 1.09 (95% CI 1.05 to 1.13, p < 0.001) for overall malformations and 1.15 (1.10 to 1.21, p < 0.001) for heart defects. Based on mean daily lorazepam-equivalent doses, the adjusted RRs for overall malformations and heart defects were 1.05 (0.99 to 1.12, p = 0.077) and 1.12 (1.04 to 1.21, p = 0.004) for <1 mg/day and 1.26 (1.17 to 1.36, p < 0.001) and 1.31 (1.19 to 1.45, p < 0.001) for >2.5 mg/day doses, respectively, suggesting a dose-response relationship. A small but significant increase in risk for overall and heart defects was detected with several specific agents (range of adjusted RRs: 1.08 to 2.43). The findings were robust across all sensitivity analyses, and negative control analyses revealed a null association. Study limitations include possible exposure misclassification, residual confounding, and restriction to live births. CONCLUSIONS: In this large nationwide cohort study, we found that first-trimester benzodiazepine exposure was associated with a small increased risk of overall malformations and heart defects, particularly at the higher daily dose. The absolute risks and population attributable fractions were modest. The benefits of benzodiazepines for their major indications must be considered despite the potential risks; if their use is necessary, the lowest effective dosage should be prescribed to minimize the risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT04856436.