Atypical antipsychotic drugs and pregnancy outcome: a prospective, cohort study.

Women of childbearing age are often affected with psychotic disorders, requiring the use of antipsychotic medication during pregnancy. In the present study, we prospectively followed the pregnancies of 561 women exposed to second-generation antipsychotic agents (SGAs; study cohort) and compared these to 284 pregnant women exposed to first-generation antipsychotic agents (FGAs; comparison cohort I) and to 1122 pregnant women using drugs known as not harmful to the unborn (comparison cohort II). Subjects were enrolled through the Institute's consultation service. Major malformation rates of SGA exposed were higher compared to comparison cohort II (adjusted odds ratio, 2.17; 95% confidence interval, 1.20-3.91), possibly reflecting a detection bias concerning atrial and ventricular septal defects. Postnatal disorders occurred significantly more often in infants prenatally exposed to SGAs (15.6%) and FGAs (21.6%) compared to 4.2% of comparison cohort II. Cumulative incidences of elective terminations of pregnancy were significantly higher in both the study cohort (17%) and comparison cohort I (21%) compared to comparison cohort II (3%), whereas the rates of spontaneous abortions did not differ. The numbers of stillbirths and neonatal deaths were within the reference range. Preterm birth and low birth weight were more common in infants exposed to FGAs. To conclude, our findings did not reveal a major teratogenic risk for SGAs, making the better studied drugs of this group a treatment option during pregnancy. Because neonates exposed to SGAs or FGAs in the last gestational week are at higher risk of postnatal disorders, delivery should be planned in clinics with neonatal intensive care units.

Binge toluene exposure in pregnancy and pre-weaning developmental consequences in rats.

Binge Toluene Exposure in Pregnancy and Pre-weaning Developmental Consequences in Rats. Bowen, S.E. and Hannigan, J.H. The persistent rate of abuse of inhaled organic solvents, especially among women of child-bearing age, raises the risk for teratogenic effects of maternal toluene abuse. In this study, timed-pregnant Sprague Dawley rats were exposed from Gestation Day (GD) 8 to GD20 to 12,000 or 8000 parts per million (ppm) toluene, or 0ppm (controls) for 30min twice daily, 60min total daily exposure. Pups were assessed from postnatal day (PN) 4 to PN21 using a developmental battery measuring growth (i.e., body weight), maturational milestones (e.g., eye opening & incisor eruption), and biobehavioral development (e.g., negative geotaxis & surface righting). Pups exposed in utero to 12,000ppm or 8000ppm toluene weighed significantly less than the non-exposed control pups beginning at PN4 and PN12 (respectively) until PN21. Toluene resulted in significant increases in an index of poor perinatal outcome, specifically a composite of malformations, defined "runting" and neonatal death. No significant delays were observed in reaching maturational milestones. The results reveal that brief, repeated, prenatal exposure to high concentrations of toluene can cause growth retardation and malformations in rats. A comparison of the present, conservative results with findings in previous studies implies that binge patterns of toluene exposure in pregnant rats modeling human solvent abuse can result in developmental and morphological deficits in offspring. These results do not exclude the possibility that maternal toxicity as well as teratogenic effects of toluene may contribute to outcomes. The results suggest that abuse of inhaled organic solvents like toluene may result in similar early developmental outcomes in humans.

Enrollment of extremely low birth weight infants in a clinical research study may not be representative.

BACKGROUND AND OBJECTIVE: The Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial (SUPPORT) antenatal consent study demonstrated that mothers of infants enrolled in the SUPPORT trial had significantly different demographics and exposure to antenatal steroids compared with mothers of eligible, but not enrolled infants. The objective of this analysis was to compare the outcomes of bronchopulmonary dysplasia, severe retinopathy of prematurity, severe intraventricular hemorrhage or periventricular leukomalacia (IVH/PVL), death, and death/severe IVH/PVL for infants enrolled in SUPPORT in comparison with eligible, but not enrolled infants. METHODS: Perinatal characteristics and neonatal outcomes were compared for enrolled and eligible but not enrolled infants in bivariate analyses. Models were created to test the effect of enrollment in SUPPORT on outcomes, controlling for perinatal characteristics. RESULTS: There were 1316 infants enrolled in SUPPORT; 3053 infants were eligible, but not enrolled. In unadjusted analyses, enrolled infants had significantly lower rates of death before discharge, severe IVH/PVL, death/severe IVH/PVL (all < 0.001), and bronchopulmonary dysplasia (P = .003) in comparison with eligible, but not enrolled infants. The rate of severe retinopathy of prematurity was not significantly different. After adjustment for perinatal factors, enrollment in the trial was not a significant predictor of any of the tested clinical outcomes. CONCLUSIONS: The results of this analysis demonstrate significant outcome differences between enrolled and eligible but not enrolled infants in a trial using antenatal consent, which were likely due to enrollment bias resulting from the antenatal consent process. Additional research and regulatory review need to be conducted to ensure that large moderate-risk trials that require antenatal consent can be conducted in such a way as to ensure the generalizability of results.

Embryonic catalase protects against endogenous and phenytoin-enhanced DNA oxidation and embryopathies in acatalasemic and human catalase-expressing mice.

Oxidative stress and reactive oxygen species (ROS) such as hydrogen peroxide (H(2)O(2)), which is detoxified by catalase, are implicated in fetal death and birth defects. However, embryonic levels of catalase are only ∼ 5% of adult activity, and its protective role is not understood completely. Herein, we used mutant catalase-deficient mice [acatalasemic (aCat)] and transgenic mice expressing human catalase (hCat), which, respectively, exhibited 40-50% reductions and 2-fold elevations in the activities of embryonic and fetal brain catalase, to show that embryonic catalase protects the embryo from both physiological oxidative stress and the ROS-initiating antiepileptic drug phenytoin. Compared to wild-type (WT) catalase-normal controls, both untreated and phenytoin-exposed aCat mice exhibited a 30% increase in embryonic DNA oxidation and a >2-fold increase in embryopathies, both of which were completely blocked by protein therapy with exogenous catalase. Conversely, compared to WT controls, untreated and, to a lesser extent, phenytoin-exposed hCat mice were protected, with untreated hCat embryos exhibiting a 40% decrease in embryonic DNA oxidation and up to a 67% decrease in embryopathies. Embryonic catalase accordingly plays an important protective role, and both physiological and phenytoin-enhanced oxidative stress can be embryopathic.

L-cysteine, N-acetyl-L-cysteine, and glutathione protect Xenopus laevis embryos against acrylamide-induced malformations and mortality in the frog embryo teratogenesis assay.

Dietary acrylamide is largely derived from heat-induced reactions between the amino group of the free amino acid asparagine and carbonyl groups of glucose and fructose during heat processing (baking, frying) of plant-derived foods such as potato fries and cereals. After consumption, acrylamide is absorbed into the circulation and is then distributed to various organs, where it can react with DNA, neurons, hemoglobin, and essential enzymes. In the present study, we explored the potential of L-cysteine (CySH), N-acetyl-L-cysteine (NAC), reduced glutathione (GSH), and the amino acid glycine (Gly) to protect frog embryos against acrylamide-induced developmental toxicity in the frog embryo teratogenesis assay - Xenopus (FETAX). To test the antiteratogenic potential, based on concentration-response study ranging from 0.07 to 4.22 mM acrylamide in FETAX solution (pH 8.1), we selected concentrations of acrylamide that induced 100% malformations and mortality. At the end of 96 h, we counted survivors and malformed embryos and measured embryo length. The data show that CySH, NAC, and GSH protected the embryos against acrylamide induced malformations and mortality to different degrees. CySH and GSH protected the embryos against both malformations and mortality, whereas NAC protected only against mortality. Gly had no protective effect. Possible mechanisms of the protective effects and the dietary significance of the results of this and related studies for food safety and human health are discussed.

Teratogenic effects of tetrabromobisphenol A on Xenopus tropicalis embryos.

Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant and a known thyroid disruptor. We reported exposing Xenopus tropicalis embryos (NF10) to 0.01, 0.1 or 1 mg/L of TBBPA with or without 70 microg/L triiodothyronine (T(3)). Compared with the controls, 1 mg/L of TBBPA significantly reduced the body length of embryos after 24, 36 and 48 h of exposure. Embryos treated with TBBPA showed multiple malformations, including: abnormal eyes, skin hypopigmentation, enlarged proctodaeum, narrow fins and pericardial edemas. The effect of abnormal eyes manifested itself in the loss of pigmentation, reduction in size, or absence of external eyes. The degree of eye malformations was quantified with the index of eye malformations (IEM) with 0 being normal and 3 being severe. In the 1 mg/L TBBPA treatment groups, the incidence of total malformations (ITM) was 68-93%, and IEM was 0.8-0.9. T(3) showed no teratogenic effects on embryos, but it significantly enhanced TBBPA-induced teratogenic effects. In the T(3)+1 mg/L TBBPA treatment groups, ITM was 91-99%, and IEM was 1.8-1.9. Histological observations showed that the retinas were generally smaller, and the lenses were underdeveloped or even absent. These results indicate that TBBPA at relatively high concentration has teratogenic effects on X. tropicalis embryos. The results also suggest that thyroid hormone signaling might be involved in TBBPA induced-teratogenicity.

Developmental effects of ethinylestradiol on reproductive organs of female mice.

Reproductive organs in female mice are susceptible to exposure to estrogenic substances especially during development. In the present study, C57BL/6J female mice were exposed to the synthetic estrogens ethinylestradiol (EE2) or diethylstilbestrol (DES), 10-100 or 6.7-67 microg/kg bw, respectively, in utero from day 10 to 18 of pregnancy, and their effects were analyzed at 30 and 40 days of age. Both EE2 and DES reduced the survival rate of fetuses and newborns in a dose-dependent manner. Polyovular follicles (PF) were found in the ovaries of all groups at 30 days of age including oil-injected controls. However, the incidence of PF was significantly higher in the 50 microg/kg EE2- and 33.3 microg/kg DES-exposed mice than the control. In vaginal epithelia of the in utero EE2 exposed, ovariectomized mice, stratification and cornification were encountered even 10 days after ovariectomy. Especially, vaginae in the ovariectomized mice given high dose of EE2 or DES in utero showed ovary-independent proliferation of the epithelium. Thus, it is clear that prenatal exposure to EE2 or DES induces reproductive abnormalities, including PF, ovary-independent vaginal epithelial stratification and cornification.

Teratogenicity of valproate conjugates with anticonvulsant activity in mice.

Valproic acid (VPA) is an effective antiepileptic medication, the use of which in females of childbearing age is complicated by its ability to induce birth defects, including neural tube defects (NTDs), in exposed embryos. In experimental settings, VPA reproducibly induces NTDs in laboratory animals such as the highly inbred SWV/Fnn mice. In search of new, efficacious derivatives of VPA that lack toxicity, the conjugates of VPA with amantadine (VPA-AMA) and N-3-aminopropyl-2-pyrrolidinone (VPA-PYR) have been synthesized and evaluated for their anticonvulsant activity. In the present study, the authors evaluated the teratogenicity potential of VPA-AMA and VPA-PYR using a well-established mouse model for antiepileptic drug teratogenicity. All tested compounds were injected intraperitoneally to pregnant dams on gestational day 8.5, and the fetuses examined on day 18.5. At the highest dose tested (3.61 mmol/kg), VPA-PYR was maternally lethal, whereas VPA-AMA induced excessive embryonic lethality. At a dose of 2.20 mmol/kg, VPA-PYR was not teratogenic to the exposed embryos; VPA-AMA induced NTDs in 8.2% of embryos, VPA caused 5.5% NTDs. 0.80 mmol/kg amantadine induced NTDs in 2.2% of the exposed fetuses. In conclusion, VPA-AMA has a comparable teratogenicity as does VPA, and it is proposed that the teratogenicity of VPA-AMA is due to the parent compound. Additional studies are needed to fully define and understand the structure-teratogenicity relationships of VPA analogues.

Prenatal window of susceptibility to perfluorooctane sulfonate-induced neonatal mortality in the Sprague-Dawley rat.

The critical period for increased neonatal mortality induced by perfluorooctane sulfonate (PFOS) exposure was evaluated in the rat. Timed-pregnant Sprague-Dawley rats were treated by oral gavage with 25 mg/kg/d PFOS/K(+) on four consecutive days (gestation days (GD) 2-5, 6-9, 10-13, 14-17, or 17-20) or with 0, 25, or 50 mg/kg/d PFOS/K(+) on GD 19-20. Controls received vehicle (10 ml/kg 0.5% Tween-20) on these days. Maternal weight gain was reduced in treated animals during dosing, as were food and water consumption. Following a 4-day treatment, litter size at birth was unaffected while pup weight was similarly reduced in the three earliest PFOS groups. All PFOS groups experienced decreases in survival while controls remained near 100%. Neonatal survival decreased in groups dosed later during gestation, approaching 100% with dosing on GD 17-20. Most deaths occurred before postnatal day (PND) 4, with the majority in the first 24 hours. Maternal serum PFOS levels on GD 21 were higher in groups exhibiting higher mortality. Following a 2-day treatment, PFOS groups experienced significant pup mortality by PND 1. Neonatal mortality continued through PND 5, when survival was 98, 66, and 3% for the 0, 25, and 50 mg/kg groups, respectively. Pup weight was reduced in treated groups with surviving litters. Gross dissection and histological examination of lungs revealed differences in maturation between control and treated animals on PND 0. We conclude that exposure to PFOS late in gestation is sufficient to induce 100% pup mortality and that inhibition of lung maturation may be involved.

Embryonic prostaglandin H synthase-2 (PHS-2) expression and benzo[a]pyrene teratogenicity in PHS-2 knockout mice.

The developmental role of prostaglandin H synthase-2 (PHS-2), which converts xenobiotics such as benzo[a]pyrene (B[a]P) to toxic free radical intermediates, is poorly understood. In this study, we determined the embryonic expression and teratological relevance of PHS-2 in pregnant CD-1 and B6/129S7 PHS-2 knockout mice. Wild-type (+/+) B6/129S7 dams given B[a]P on gestational day (GD) 10 had three times more fetal malformations than did +/- PHS-2-deficient dams (P<0.05). GD 10-13 CD-1 embryos had high PHS-2 protein expression, and both + /+ and +/- GD 19 B6/129S7 fetuses had more B[a]P-initiated malformations and postpartum lethality than did -/- littermates (P<0.05). Thus, embryonic PHS-2 is expressed constitutively during organogenesis and contributes substantially to B[a]P teratogenicity.

Stage- and species-specific developmental toxicity of all-trans retinoic acid in four native North American ranids and Xenopus laevis.

Within the last decade, there have been increasing reports of malformed amphibians across North America. Recently, it has been suggested that hind-limb malformations are a consequence of xenobiotic disruption of developmental pathways regulated by retinoids. To assess the validity of this hypothesis, the developmental toxicity of all-trans retinoic acid (RA) was examined in Xenopus laevis and four North American anurans, at several life stages. To determine the effects of RA on embryogenesis, mid-blastula stage embryos were exposed to 0, 6.25, 12.5, 25, or 50 ng RA/ml for 24 h. To evaluate the effects of RA on hind-limb development, early- and mid-limb bud stage tadpoles were exposed to RA concentrations of 0, 250, 500, 750, 1000, or 1250 ng RA/ml for 24 h. Mid-blastula RA exposure resulted in a concentration-dependent increase in dysmorphogenesis and mortality in the three species examined (R. clamitans, R. septentrionalis and X. laevis). RA exposure at stage 51 in X. laevis and stage 28 in R. sylvatica resulted in concentration-dependent increases in reductions and deletions of the hind limb. However, RA was ineffective at inducing hind-limb abnormalities in stages 26 and 28 of R. pipiens, stage 28 in R. clamitans, or stage 48 in X. laevis tadpoles. These results indicate that mid-blastula stage embryos are more sensitive to RA-induced dysmorphogenesis and mortality than limb-bud stage tadpoles. The significance of these findings is discussed in the context of the possible occurrence of retinoid mimics in the environment.

Assessing the predictive validity of frog embryo teratogenesis assay-Xenopus (FETAX).

The ability of frog embryo teratogenesis assay - Xenopus (FETAX) to identify the potential developmental toxicity of a group of diverse chemicals was evaluated by comparison with results from in vivo studies in rats. A total of 12 chemicals, three of which were shown to be teratogenic in vivo, four of which were embryolethal (but not teratogenic) in vivo, and five which did not produce any developmental toxicity in vivo in the rat were evaluated using FETAX. Results of the FETAX test with these 12 blind-coded compounds correctly predicted that three chemicals had strong teratogenic potential, four had low teratogenic hazard potential but were embryolethal, and five posed little if any developmental toxicity hazard. In addition, this study concluded that within a family of chemistry analogs could be ranked according to relative teratogenic hazard and that for the teratogenic compounds the types of malformations induced in Xenopus mimicked the abnormalities induced in vivo in rats. In summary, these results confirmed that the FETAX assay is predictive and can be useful in an integrated biological hazard assessment for the preliminary screening of chemicals. Teratogenesis Carcinog. Mutagen. 20:87-98, 2000.

An avian model for comparative studies of insulin teratogenicity.

This study was designed to explore the effects of purified insulin during early stages of chick embryo development, and to search for variations between different molecular structures of the hormone. Chicken embryos were treated in ovo with a single dose of insulin (porcine or bovine), in only one stage of development between day 0 and day 9. Two susceptible periods were found. The earliest period (day 0 to day 3), characterized by abnormalities in the caudal vertebrae and a high mortality rate, was followed by a period with a different set of malformations, a syndrome classified as achondroplasia. The rate of achondroplastic embryos was significantly higher with porcine rather than with bovine insulin. Paradoxically, insulin at physiological doses has stimulatory effects in growth and development but, in contrast, has inhibitory effects at higher doses. The precise signalling cascade of events in the target cells is still unclear. The possible interpretations of our results are discussed. The similarity between the insulin-induced abnormalities in the chicken embryos and the caudal regression syndrome, the most common malformation found in infants of diabetic women, suggests a common mechanism. This circumstance offers the chicken embryos as an excellent in vivo model for research on the mechanism of action of insulin during normal and abnormal development.

Toxicological assessment of biodegraded pentachlorophenol: Microtox and fish embryos.

A Gram-negative bacterium, Pseudomonas sp. strain SR3, was isolated from soil at a former wood treatment plant in north central Florida. The ability of this bacterium to degrade pentachlorophenol (PCP) was confirmed by growing cells in a basal salts medium in which PCP was the only source of carbon and energy. Degradation from a measured concentration of 39-40 micrograms PCP/ml to 0.0006 micrograms PCP/ml was observed within 120 h of incubation in the presence of PCP-induced cells of Pseudomonas sp. strain SR3. The initial cell density in these cultures was 6 x 10(6) cfu/ml. Microtox 5 min EC50 toxicity tests revealed that aqueous solutions of PCP, measured concentrations 39-40 micrograms/ml were toxic but that final biodegraded samples, 0.0006 micrograms PCP/ml were nontoxic. However, bioassays with embryonic inland silversides, Menidia beryllina, showed that the biodegraded samples were embryotoxic or teratogenic. Water containing added PCP at concentrations up to 30 times higher than measured in the final biodegraded samples was less toxic/teratogenic. These results indicate that while biodegradation of PCP was nearly complete, intermediate metabolites of the degradation process or undegraded impurities in PCP were toxic or teratogenic. Thus, the M. beryllina bioassay allows extremely sensitive assessment of toxicity associated with biodegraded environmental pollutants and may be a useful criterion for determining whether bioremediated water or soil is safe for discharge back into the environment.

Effects of diethylene glycol monomethyl ether on pregnancy and postnatal development in rats.

The effects of oral treatment of Wistar rats with diethylene glycol monomethyl ether (diEGME) were examined. In a preliminary dose-finding study with non-pregnant rats, diEGME treatment at doses up to 4,000 mg/kg/day on 11 consecutive days decreased relative weights of thymus and pituitary gland, white and red blood cell counts, hemoglobin concentrations and hematocrit levels. In pregnant rats, treatment at doses of > 3,000 mg/kg/day (over gestation days 7-17) caused total resorption of all litters. In teratology and postnatal studies, pregnant rats were treated with diEGME at doses of 0, 200, 600, and 1,800 mg/kg/day from day 7 through 17 of gestation. At 200 mg/kg, there were no adverse effects on either dams, fetuses, or neonates. At 600 mg/kg, dams were not affected, but fetal body weights were decreased, and fetal thymus and ossification were adversely affected. At 1,800 mg/kg, maternal thymus weights and food consumption were decreased, and visceral malformations of the cardiovascular system were seen in 28.0% of the fetuses. Only 6.3% of the pups delivered by dams treated with 1,800 mg/kg of diEGME survived for 4 days after birth. Thus, diEGME was teratogenic in Wistar rats, but the spectrum differed from that in Sprague-Dawley rats. In addition to teratogenicity, diEGME had significant adverse effects on postnatal development. The most sensitive organ to diEGME was the thymus in both dams and fetuses.