Human teratogens: Update 2010

A comparison of infants' birth defects self-reported by mothers with data provided by general practitioners: Data from the Dutch Pregnancy Drug Register

BACKGROUND

Since the presence of a birth defect is often a primary outcome in drug-safety studies among pregnant women, researching the validity of data collection methods is imperative. The aim of this study is to compare self-reported birth defects in infants by mothers with the information provided by general practitioners (GP (singular) or GPs (plural)).

METHODS

Mothers who participated in the Dutch Pregnancy Drug Register reported information about possible birth defects of their infants via questionnaires. GPs were approached to provide information on possible birth defects of the same infants. All reported birth defects by mothers and GPs were blindly coded using the International Classification of Diseases, Tenth Revision (ICD-10) index and EUROCAT-classified as either a minor or major birth defect. Differences in reported birth defects between participants and GPs were assessed.

RESULTS

Participants and GPs (N = 551) reported 67 and 53 birth defects respectively, leading to a total of 120 birth defects among 65 infants. When both the GP and the participant reported a birth defect, 76.9% of these birth defects (N = 60) were coded with an identical ICD-10 code. Information on the absence of a birth defect and the presence of a major birth defect was identically reported by the GP and the mother in almost all cases (98.2%). Of the major birth defects reported by the GP, 67% could be matched with information provided by the participant, for 33% contradicting information was reported.

CONCLUSION

Self-reported questionnaire data on infants' birth defects from mothers yield fairly similar information compared to information obtained through GPs. Future studies should validate the accuracy of self-reported birth defects by mothers more extensively to improve the quality of drug safety studies during pregnancy.

Maternal fever during pregnancy and offspring attention deficit hyperactivity disorder

Maternal fever during pregnancy is associated with several adverse child outcomes. We investigated associations between maternal fever and ADHD among offspring, as well as the sub-dimensions of ADHD - inattention and hyperactivity/impulsivity. Data came from the Norwegian Mother and Child Cohort Study, including more than 114,000 children. Information about children’s ADHD diagnoses was obtained from the Norwegian Patient Register. Mothers reported on inattention and hyperactivity/impulsivity symptoms in questionnaires at 8 years. Logistic regression analysis showed that children exposed to maternal fever in the first trimester received an ADHD diagnosis more often than unexposed children (Odds Ratio (OR) = 1.31, 95% confidence interval (CI) = 1.06–1.61). For children exposed twice or more in the first trimester, the OR was 2.64 (CI = 1.36–5.14). Linear regression analysis showed elevated inattention symptoms among children exposed to fever in the first (Cohen’s d = 0.09, CI = 0.03–0.15) and second (Cohen’s d = 0.05, CI = 0.01–0.09) trimester. Results were similar whether the mother had taken acetaminophen for their fever or not. Hyperactivity/impulsivity symptoms were not related to maternal fever. The results indicate that maternal fever in early pregnancy may be a risk factor for ADHD, and particularly for inattention problems. This risk is neither mitigated nor inflated by use of acetaminophen.

Insights into Molecular Interactions of human Wnt5b and Frizzled proteins for their role in teratogenicity

Wnt-Fzd signalling plays vital role in different physiological pathways including embryonic development and supposed to be probable target of many teratogens. The present study was done to investigate the role of human Wnt5b interaction with different isoforms of human Fzds and also the molecular interactions of their complexes with selected known teratogens [Carbamazepine (CBZ), Retinoic acid (RA), Valproic acid (VPA), Aminopterin (AMP) and Phenytoin (PHY)] using Niclosamide (NLM) as standard. The models of hWnt5b and hFzd isoforms, whose solved crystal structures were unavailable, were generated using homology modeling and hWnt5b was subjected to protein-protein docking studies against different isoforms of hFzd. The macromolecular docking studies of hWnt5b-hFzds complexes revealed that hWnt5b had highest binding affinity with hFzd8 and lowest with hFzd1, respectively. The Cysteine rich domain (CRD) of hFzds docked against hWnt5b into a palm shaped opening or near the largest binding pocket as in hWnt5b-hFzd6. The possible role of Wnt-Fzd interactions in developmental toxicity due to selected teratogens were also investigated using molecular docking studies which showed that Retinoic Acid possessed the maximum binding affinity with binding energy of for hWnt5b-hFzd8 complex while VPA was observed to have lowest binding affinity towards all the studied hWnt5b-hFzd complexes.

Effects of prenatal exercise on incidence of congenital anomalies and hyperthermia: a systematic review and meta-analysis

OBJECTIVE

To investigate the relationships between exercise and incidence of congenital anomalies and hyperthermia.

DESIGN

Systematic review with random-effects meta-analysis .

DATA SOURCES

Online databases were searched from inception up to 6 January 2017.

STUDY ELIGIBILITY CRITERIA

Studies of all designs were eligible (except case studies and reviews) if they were published in English, Spanish or French, and contained information on population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone ["exercise-only"] or in combination with other intervention components [e.g., dietary; "exercise + co-intervention"]), comparator (no exercise or different frequency, intensity, duration, volume or type of exercise) and outcome (maternal temperature and fetal anomalies).

RESULTS

This systematic review and meta-analysis included 'very low' quality evidence from 14 studies (n=78 735) reporting on prenatal exercise and the odds of congenital anomalies, and 'very low' to 'low' quality evidence from 15 studies (n=447) reporting on maternal temperature response to prenatal exercise. Prenatal exercise did not increase the odds of congenital anomalies (OR 1.23, 95% CI 0.77 to 1.95, I²=0%). A small but significant increase in maternal temperature was observed from pre-exercise to both during and immediately after exercise (during: 0.26°C, 95% CI 0.12 to 0.40, I²=70%; following: 0.24°C, 95% CI 0.17 to 0.31, I²=47%).

SUMMARY/CONCLUSIONS

These data suggest that moderate-to-vigorous prenatal exercise does not induce hyperthermia or increase the odds of congenital anomalies. However, exercise responses were investigated in most studies after 12 weeks' gestation when the risk of de novo congenital anomalies is negligible.

Protected to death: systematic exclusion of pregnant women from Ebola virus disease trials

BACKGROUND

For 30 years, women have sought equal opportunity to be included in trials so that drugs are equitably studied in women as well as men; regulatory guidelines have changed accordingly. Pregnant women, however, continue to be excluded from trials for non-obstetric conditions, though they have been included for trials of life-threatening diseases because prospects for maternal survival outweighed potential fetal risks. Ebola virus disease is a life-threatening infection without approved treatments or vaccines. Previous Ebola virus (EBOV) outbreak data showed 89-93% maternal and 100% fetal/neonatal mortality. Early in the 2013-2016 EBOV epidemic, an expert panel pointed to these high mortality rates and the need to prioritize and preferentially allocate unregistered interventions in favor of pregnant women (and children). Despite these recommendations and multiple ethics committee requests for their inclusion on grounds of justice, equity, and medical need, pregnant women were excluded from all drug and vaccine trials in the affected countries, either without justification or on grounds of potential fetal harm. An opportunity to offer pregnant women the same access to potentially life-saving interventions as others, and to obtain data to inform their future use, was lost. Once again, pregnant women were denied autonomy and their right to decide.

CONCLUSION

We recommend that, without clear justification for exclusion, pregnant women are included in clinical trials for EBOV and other life-threatening conditions, with lay language on risks and benefits in information documents, so that pregnant women can make their own decision to participate. Their automatic exclusion from trials for other conditions should be questioned.

Impact of selective serotonin reuptake inhibitors on neural crest stem cell formation

The use of antidepressants in pregnant women is rising, with rates up to 7.5% in the United States. Selective serotonin reuptake inhibitors (SSRIs) are currently the most common antidepressant prescribed to pregnant women. The teratogenic effects of SSRI exposure are debated because of discrepancies in epidemiological studies. As an alternative to epidemiological and animal studies, human embryonic stem cell research (hESC) provides a human-based experimental model to examine the risks of prenatal SSRI exposure. Neural crest stem cells (NCSCs) play an important role in craniofacial and cardiac development as precursors to craniofacial bones and heart septa. This study examines the effects of paroxetine (Paxil) and sertraline (Zoloft) exposure on proliferation, migration, and AP-2α protein expression of NCSC in vitro. hESCs were exposed to paroxetine and sertraline at three concentrations while undergoing directed differentiation into NCSCs. Our results indicate exposure to paroxetine significantly increased proliferation, migration, and AP-2α protein expression in NCSCs. Exposure to sertraline significantly decreased proliferation and significantly increased AP-2α protein expression in NCSC. This evidence suggests paroxetine and sertraline alter normal NCSC behavior and may thereby disrupt cardiac and craniofacial development.

Exposure of hospitalised pregnant women to plasticizers contained in medical devices

Background

Medical devices (MDs) in polyvinyl chloride (PVC) are not a well-known source of exposure to plasticizers, in particular during pregnancy. Because of its toxicity, the di-(2-ethylhexyl) phthalate (DEHP) has been replaced by other plasticizers such as di (isononyl)-cyclohexane-1,2-dicarboxilic acid (DINCH), tri-octyltrimellitate (TOTM) and di-(isononyl) phthalate (DiNP). Our study aimed to quantify the plasticizers (DEHP and alternative plasticizers) contained in PVC medical devices used for hospitalised pregnant women and to describe which these MDs had been used (type, number, duration of exposure).

Methods

The plasticizers contained in the MDs used for daily care in the Obstetrics Department of a French University Hospital were extracted from PVC (after contact with a chloroform solution), identified and quantified by gas-chromatography-mass-spectrometry analysis. A total of 168 pregnant women hospitalised in the Obstetrics Department with at least one catheter were included in the observational study. The median number of MDs containing plasticizers used and the daily duration of exposure to the MDs were compared in three groups of pregnant women: “Pathology group” (women hospitalised for an obstetric disorder who did not give birth during this hospitalisation; n = 52), “Pathology and delivery group” (hospitalised for an obstetric disorder and who gave birth during this stay; n = 23) and “Delivery group” (admitted for planned or spontaneous delivery without obstetric disorder; n = 93).

Results

DiNP, TOTM and DINCH were the predominant plasticizers contained in the MDs at an amount of 29 to 36 g per 100 g of PVC. Women in the “Pathology group” (preterm labour or other pathology) were exposed to a median number of two MDs containing TOTM and one MD containing DiNP, fewer than those in the “Pathology and delivery group” (p < 0.05). Women in the “Pathology group” had a median exposure of 3.4 h/day to MDs containing DiNP and 8.2 h/day to MDs containing TOTM, longer than those in the “Delivery group” (p < 0.01).

Conclusions

Our study shows that the medical management of pregnant women in a hospital setting entails exposure to MDs containing alternative plasticizers (DiNP, TOTM and DINCH).

Electronic supplementary material

The online version of this article (doi:10.1186/s12905-017-0398-7) contains supplementary material, which is available to authorized users.

AISF position paper on liver transplantation and pregnancy: Women in Hepatology Group, Italian Association for the Study of the Liver (AISF)

After the first successful pregnancy in a liver transplant recipient in 1978, much evidence has accumulated on the course, outcomes and management strategies of pregnancy following liver transplantation. Generally, liver transplantation restores sexual function and fertility as early as a few months after transplant. Considering that one third of all liver transplant recipients are women, that approximately one-third of them are of reproductive age (18-49 years), and that 15% of female liver transplant recipients are paediatric patients who have a >70% probability of reaching reproductive age, the issue of pregnancy after liver transplantation is rather relevant, and obstetricians, paediatricians, and transplant hepatologists ever more frequently encounter such patients. Pregnancy outcomes for both the mother and infant in liver transplant recipients are generally good, but there is an increased incidence of preterm delivery, hypertension/preeclampsia, foetal growth restriction, and gestational diabetes, which, by definition, render pregnancy in liver transplant recipients a high-risk one. In contrast, the risk of congenital anomalies and the live birth rate are comparable to those of the general population. Currently there are still no robust guidelines on the management of pregnancies after liver transplantation. The aim of this position paper is to review the available evidence on pregnancy in liver transplant recipients and to provide national Italian recommendations for clinicians caring for these patients.

Triple Therapy with Prednisolone, Pegylated Interferon and Sodium Valproate Improves Clinical Outcome and Reduces Human T-Cell Leukemia Virus Type 1 (HTLV-1) Proviral Load, Tax and HBZ mRNA Expression in Patients with HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis

Considering that there is no effective treatment for human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis, this study aimed to assess the impact of triple combination therapy-interferon-α, valproic acid, and prednisolone-on clinical outcomes, main HTLV-1 viral factors, and host anti-HTLV-1 antibody response. HTLV-1 proviral load (PVL), and HBZ and Tax mRNA expression levels were measured in peripheral blood mononuclear cells of 13 patients with HTLV-1-associated myelopathy/tropical spastic paraparesis before and after treatment with 180 μg pegylated interferon once a week, 10-20 mg/kg/day sodium valproate, and 5 mg/day prednisolone for 25 weeks using a TaqMan real-time polymerase chain reaction assay. Furthermore, anti-HTLV-1 titer, Osame Motor Disability Score, Ashworth spasticity scale, and urinary symptoms (through standard questionnaire and clinical monitoring) were assessed in patients before and after the treatment. HTLV-1 PVL and HBZ expression significantly decreased after the treatment [PVL from 1443 ± 282 to 660 ± 137 copies/10(4) peripheral blood mononuclear cells (p = 0.01); and HBZ from 8.0 ± 1.5 to 3.0 ± 0.66 (p < 0.01)]. Tax mRNA expression decreased after the treatment from 2.26 ± 0.45 to 1.44 ± 0.64, but this reduction was not statistically significant (p = 0.10). Furthermore, anti-HTLV-1 titer reduced dramatically after the treatment, from 3123 ± 395 to 815 ± 239 (p < 0.01). Clinical signs and symptoms, according to Osame Motor Disability Score and Ashworth score, improved significantly (both p < 0.01). Urinary symptoms and sensory disturbances with lower back pain were reduced, though not to a statistically significant degree. Although signs and symptoms of spasticity were improved, frequent urination and urinary incontinence were not significantly affected by the triple therapy. The results provide new insight into the complicated conditions underlying HTLV-1-associated diseases.

Assessing congenital malformation risk from medications used in pregnancy: The contribution of NBDPS in pregnancy labeling of prescription drug products

BACKGROUND

Obtaining human pregnancy data to inform product labeling is important for drug and biological products.

METHODS

Collection and analyses of safety data on their use during pregnancy is usually performed after approval.

RESULTS

The Centers for Disease Control National Birth Defects Prevention Study has provided important data on the relationship between drug use in pregnancy and birth defects.

CONCLUSION

The Pregnancy and Lactation Labeling Rule will set new and improved standards for the inclusion of information about the use of prescription drugs and biological products during pregnancy; the National Birth Defects Prevention Study, along with other data sources, will be critical for providing safety data to inform product labeling.

Are epidemiological approaches suitable to study risk/preventive factors for human birth defects?

Birth defects are a major cause of infant morbidity and mortality and contribute substantially to long-term disability. One out of every 33 babies is born with some type of birth defect. Despite decades of research on environmental, behavioral and genetic risk factors, the vast majority of birth defects still occur without known cause. It is possible that birth defects are largely stochastic (and unavoidable) events, at which efforts to investigate their causes would be futile and unjustified. In this commentary we argue for the continued research into risk/preventive factors of human birth defects, and outline why epidemiological studies are suitable for such endeavors. First we discuss what factors to target (genetic or environmental) and how to define the pertinent research questions. Then we present a short review of both epidemiological contributions in the past and approaches to advance the field in the future. After considering also their limitations, we conclude that modern epidemiologic approaches are invaluable to advance our understanding of risk factors for human birth defects, and that interdisciplinary collaborations will also be essential to further our knowledge.

[Factors associated with use of medication during first pregnancies in Rio Branco, Acre State, Brazil]

This cross-sectional study in a sample of 887 primigravidae in Rio Branco, Acre State, Brazil aimed to analyze factors associated with the use of medicines during the first pregnancy. Information was obtained from interviews and prenatal cards. Medicines were classified according to the Anatomical Therapeutic Chemical (ATC) Classification System of the World Health Organization and risk categories according to the U.S. Food and Drug Administration. Mean age was 21 years and mean number of medicines used was 2.42. The most frequently consumed medicines were antianemics (47.5%), supplements and vitamins (18.7%), analgesics (13.8%), and antibiotics (10.5%). In the risk categorization, 69.3% belonged to category A, 22.3% to B, 7.6% to C, and 0.8% to D. The odds of having used risky medicines were higher among primigravidae in unit B (OR = 2.10; 95%CI: 1.26-3.50), in the 19 to 24-year age bracket (OR = 2.79; 95%CI: 1.58-4.93), and in the presence of a medical prescription (OR = 1.86; 95%CI: 1.18-2.95). Essential drugs were less used by women with higher family income (OR = 0.63; 95%CI: 0.42-0.96) and those who had received private prenatal care (OR = 0.53; 95%CI: 0.38-0.74).

Use of medicines with unknown fetal risk among parturient women from the 2004 Pelotas Birth Cohort (Brazil)

Background. To estimate the exposure to medicines with unknown fetal risk during pregnancy and to analyze the maternal characteristics associated with it. Methods. A questionnaire was administered to 4,189 mothers of children belonging to the 2004 Pelotas (Brazil) birth cohort study about use of any medicine during gestation. We evaluated the associations between use of medicines with unknown fetal risk and the independent variables through logistic regression models. Unknown fetal risk was defined as medicines in which studies in animals have revealed adverse effects on the fetus, and no controlled studies in women, or studies in women and animals, are available. Results. Out of the 4,189 women, 52.5% used at least one medicine from unknown fetal risk. Use of these medicines was associated with white skin color, high schooling, high income, six or more antenatal care consultations, hospital admission during pregnancy, and morbidity during gestation. Conclusion. The use of unknown fetal risk medicines is high, suggesting that their use must be addressed with caution with the aim of restricting their use to cases in which the benefits are greater than the potential risks.

Pregnancy and fetal outcomes after exposure to mefloquine in the pre- and periconception period and during pregnancy

Pregnant women who travel to malarious areas and their clinicians need data on the safety of malaria chemoprophylaxis. The drug safety database analysis of mefloquine exposure in pregnancy showed that the birth defect prevalence and fetal loss in maternal, prospectively-monitored cases were comparable to background rates.

Background. Pregnant women who travel to malarious areas and their clinicians need data on the safety of malaria chemoprophylaxis.

Methods. The effect of exposure to mefloquine on pregnancy and offspring outcomes was evaluated using the F. Hoffmann–La Roche global drug safety database for the time frame 31 January 1986 through 26 October 2010. We investigated pregnancy and fetal outcomes in maternal, paternal, and both-parent exposure cases with a focus on congenital malformations and fetal loss. The main outcome measures were birth defect prevalence and types of malformations.

Results. A total of 2506 cases of mefloquine exposure during pregnancy or in the pre- and periconception period were evaluated. Most cases were maternal prospective (outcome of the pregnancy unknown at the time of reporting; n = 2246 [89.6%]) followed by maternal retrospective cases (outcome of the pregnancy known at the time of reporting; n = 227 [9.0%]), with small numbers of paternal and both-parent exposure cases. Of the total 2246 mefloquine maternal prospective exposures (95.2%), 2139 occurred before conception and/or during the first trimester. Of 1383 maternal prospective cases with known outcome, 978 (70.7%) resulted in delivery, 405 (29.3%) resulted in abortion (112 spontaneous, 293 therapeutic), and 43 resulted in birth defects, corresponding to a birth defect prevalence of 4.39% (43 of 978). Prospective cases overall showed no specific pattern of birth malformations.

Conclusions. The drug safety database analysis of mefloquine exposure in pregnancy showed that the birth defect prevalence and fetal loss in maternal, prospectively monitored cases were comparable to background rates.

[The thalidomide experience: review of its effects 50 years later]

This year is the 50(th) anniversary of the discovery that the drug thalidomide causes birth defects and should therefore be considered as a teratogen. However, despite the existence of several other drugs that are also human teratogens, thalidomide continues to cause concern among health professionals as well as the general population. The objectives of this article are to make a short historical review of the discovery that this drug severely alters the embryo development, the critical period of gestation and the identification of the real effect of thalidomide. For the first time an analysis is provided to identify the type of malformations for which thalidomide really increases the risk. The proportions of the different types of malformations groups from the series of patients considered to be affected by thalidomide from the literature were compared with the proportions of the same malformations groups in non-exposed infants from the Spanish Collaborative Study of Congenital Malformation (ECEMC). The aim of the analysis was to calculate the relative frequencies of 13 groups of malformations observed in series of patients exposed to thalidomide, by comparison with the same groups of defects in 1,491 patients with limb malformations from the ECEMC consecutive newborn infants, non-exposed to thalidomide. The results showed that the groups with the most classical limb malformations attributed to thalidomide (phocomelia, thumb absence/hypoplasia) had a significantly very higher frequency in exposed cases than in the ECEMC's cases. However, cases presenting with only lower limb malformations were 3 times less frequent in thalidomide cases than in those of ECEMC. Finally, other groups presented the same frequency as those observed in the ECEMC's cases. The results of the 2 last groups, strongly suggests that they were not due to the effect of thalidomide. In addition to the short historical review of the teratogenicity risk of thalidomide, and their new therapeutic properties, it is documented that, as it happens with all other currently known human teratogens, not all malformations observed in infants prenatally exposed to thalidomide were caused by this drug. Finally, it is discussed the paradox that the «feared» thalidomide drug causing a great human drama affecting about 10,000 infants has led to a formidable contribution to the scientific knowledge, and large range of therapeutic applications.

Monitoring for teratogenic signals: pregnancy registries and surveillance methods

Pregnant women should have access to medications that have been adequately studied for use to facilitate evidence-based risk-benefit discussions with their health care providers. Pregnant women experience acute medical emergencies, have existing conditions that require continued medical treatment or may develop pregnancy-induced conditions, making drug use during pregnancy unavoidable. Drug labeling is the primary source of information about a drug's use. The safety and efficacy data found in the label is derived from well-controlled clinical trials conducted prior to a drug's approval. However, pregnant women are rarely enrolled in clinical trials unless a product is specifically indicated for a pregnancy-related condition. Consequently, information regarding a product's use during pregnancy is usually collected postapproval. Current data collection tools include pregnancy exposure registries, retrospective cohort studies, pregnancy surveillance programs, case-control studies, spontaneous reports of adverse events and case reports. Each tool has strengths and limitations in its ability to detect teratogenic signals. Combinations of different sources of data are necessary to acquire the most complete picture of potential teratogenic risk, as no single method can capture all desired data to help pregnant patients and women of child bearing potential make appropriate risk benefits decisions along with their health care providers.

Adverse drug reactions in newborns, infants and toddlers: pediatric pharmacovigilance between present and future

INTRODUCTION

The detection, assessment, understanding and prevention of adverse drug reactions (ADRs) are the primary aims of pharmacovigilance activities. Pediatric patients, especially all newborns and infants, are particularly at risk for experiencing drug-related adverse events.

AREAS COVERED

This review briefly analyzes the physiological peculiarities of pharmacodynamic and pharmacokinetic aspects of drugs in newborns, infants and toddlers and children. It also deals with specific pediatric pharmacovigilance aspects, such as the frequent use of unlicensed and/or off-label drugs in neonatal intensive care units in European countries and in Australia. This review reports on European, American and Canadian data about the incidence and type of pediatric ADRs, particularly focusing on neonates, infants and toddlers.

EXPERT OPINION

The awareness of pediatricians about the importance of reporting ADRs should be stimulated, new reporting systems should be encouraged and pediatric pharmacovigilance activities should be improved, first, by intensifying active post-marketing surveillance methods.