Outcome of twin pregnancies complicated by single intrauterine death in relation to vascular anatomy of the monochorionic placenta.
(41/1902)
The objective of this study was to determine the relationship between the type of placentation, vascular anatomy of the monochorionic (MC) placenta and the perinatal outcome of the surviving twin following a single intrauterine fetal death (IUFD). In this retrospective study, 92 twin pregnancies complicated by a single intrauterine death were identified from three tertiary referral centres [50 MC and 42 dichorionic (DC)]. Antenatal and neonatal data as well as information on the chorionicity, vascular anastomoses, and autopsy findings were also obtained. The percentage risk of IUFD (26 versus 2.4; P < 0.001), anaemia (51.4 versus 0; P < 0.001) and intracranial lesions at birth (46 versus 0; P < 0.001) was greater in MC than in DC twins. In MC twins without twin-twin transfusion syndrome (TTTS), perinatal mortality was higher in the group with superficial arterioarterial (AA)/venovenous (VV) channels than those with only multiple bidirectional arteriovenous (AV) anastomoses (12/15 versus 0/8; P < 0.001). However, in the TTTS pregnancies (n = 26), perinatal outcome of the surviving twin was dependent on whether the recipient (n = 16) or the donor twin (n = 10) died first. Incidence of IUFD (9/16 versus 0/10; P < 0.001), severe anaemia (7/7 versus 1/10; P < 0.001) and intracranial lesions at birth (6/7 versus 2/10; P < 0.001) was common in pregnancies where the recipient twin died first. In the TTTS group, unidirectional AV anastomotic channels were found in all but two placentae. In conclusion, this study suggests that the outcome of twin pregnancies complicated by IUFD is dependent on the type of vascular anastomoses and TTTS. (+info)
Long-term prognosis of pregnancies complicated by slow embryonic heart rates in the early first trimester.
(42/1902)
Slow embryonic heart rates at gestational age 7 weeks or less are associated with high risk of first trimester death. Our goal was to determine the prognosis for those embryos with slow early heart rates who survive the first trimester. We prospectively recorded embryonic heart rates for all obstetrical sonograms obtained on singleton pregnancies at or before 7.0 weeks' gestation since 1993. We collected information about pregnancy outcome, including date of live birth or in utero death and presence and nature of congenital anomalies. First trimester survival rate was 61.6% among 531 embryos with slow early heart rates (< 100 bpm at < or = 6.2 weeks, < 120 bpm at 6.3 to 7.0 weeks), lower than the survival rate of 91.5% among 1501 embryos with normal heart rates (p < 10(-8), Fisher's exact test). Among 299 pregnancies in which the early heart rate was slow and the fetus was still alive at the end of the first trimester, 277 (92.6%) resulted in liveborn infants without congenital anomalies, similar to the frequency of 95.1% in cases with normal early heart rates (p > 0.10, Fisher's exact test). Structural and chromosomal anomalies, however, occurred more than twice as frequently in cases with slow early heart rates: 5.4% (16 of 299) of the first trimester survivors with slow early heart rates proved to have anomalies, as compared to 2.4% (31 of 1281) of cases with normal early heart rates (p < 0.05, Fisher's exact test). In conclusion, a pregnancy in which the embryo has a slow heart rate at or before 7.0 weeks' gestation and which continues beyond the first trimester has a high likelihood (> 90%) of resulting in a liveborn neonate without congenital anomalies. Embryos with slow early heart rates do, however, have a greater risk of having anomalies than embryos with normal early heart rates. (+info)
Animal models of the antiphospholipid syndrome.
(43/1902)
The antiphospholipid antibody syndrome (APS) is characterized by thrombocytopenia, recurrent thromboembolic phenomena and recurrent fetal loss, in association with anticardiolipin antibodies (aCL) and/or lupus anticoagulant (LA). Owing to the ethical and practical restrictions of experimentation on humans, we have to look to animal experimentation to broaden our knowledge of the pathogenesis and management of APS. Work has been carried out predominantly on strains of naive mice in which APS has been induced, passively and actively, using autoantibodies, autoantigens and other antigens. Studies of autoimmune-prone mice and naive rabbits are present in the literature, to a lesser degree. We review the various animal models of the pathogenesis of APS, whether spontaneous or induced, which have been developed over the years. Although several of the models have provided insights into the relationship between antiphospholipid antibodies and fetal loss, very few give guidance to explain the link with thrombosis. Novel or experimental therapeutic regimens have to be tested on appropriate animal models before any kind of human clinical trials may proceed. The regimens devised thus far are also reviewed. (+info)
Pregnancy outcome in Thai patients with systemic lupus erythematosus.
(44/1902)
The outcome of 48 pregnancies from 42 patients with systemic lupus erythematosus was studied. Their mean age and the duration of the disease were 28.47 and 4.42 years, respectively. The conception occurred when the disease was inactive or quiescent in 45 and active in 3. Four pregnancies were terminated by criminal abortion. Flares occurred in 16 pregnancies. The kidney and mucocutaneous system were the 2 organs that flared most commonly. The fetal outcomes were term delivery in 18 (40.90%), prematurity in 17 (38.64%), spontaneous abortion in 6 (13.64%) and still birth in 3 (6.82%). There was no statistical difference in pregnancy loss and successful delivery between pregnant patients with and without flares. Concerning 35 successful live births, those pregnancies without flares had significantly more full term deliveries (p < 0.02), higher gestational age (p < 0.002) and more birth weight (p < 0.001) than those with flares. Small for gestational age was seen in 20%. Pregnancy with active renal disease had a poor fetal outcome. There were no cases of congenital anomalies or neonatal lupus. Maternal complications were more common in patients with flares. (+info)
Trajectories of fetal loss in the Czech Republic.
(45/1902)
Using data for 555,038 pregnancies conceived in the Czech Republic in 1987-1990, we show that pronounced differences in fetal survival in the middle trimester of pregnancy by marital status, educational level, and labor force attachment become much smaller at full term; survival differences by age at conception and number of previous deliveries show relatively constant proportional hazards throughout gestation. Social inequalities in postpartum life chances have been documented previously, but we show that similar inequalities exist before birth. (+info)
A modified method for the epidemiological analysis of registry data on infants with multiple malformations.
(46/1902)
BACKGROUND: Infants with multiple malformations are important in birth defect epidemiology and malformation monitoring because human teratogens have often caused complex malformations. Various methods for the analysis of multimalformed infants have been tried. METHOD: By using data from four large registries of congenital malformations, 5256 infants were identified with two or more among 73 selected malformations. Pairwise associations between malformations were detected by multiple logistic regression analyses, and putative confounders (programme, maternal age, autopsy, etc.) were controlled for. For each significant pairwise association, further analyses were performed in order to find associations with a possible third malformation. RESULTS: The importance of controlling for several confounders was demonstrated. Several well-known associations were found, which supports the technique used. The interpretation of three-way associations was discussed. Results from the present study were compared with those obtained using some other methods. CONCLUSIONS: Different confounders can cause biased associations. The method presented in the paper takes this into consideration and is therefore more likely than previously used techniques to give unbiased information on the clustering of different malformations among multimalformed infants. (+info)
Pregnancy outcomes and outdoor air pollution: an ecological study in districts of the Czech Republic 1986-8.
(47/1902)
OBJECTIVES: Outdoor air pollution has consistently been shown to predict mortality. The finding that this association is stronger in infants than in children or adults raises the question whether air pollution could also be related to pregnancy outcomes--such as birthweight and stillbirth. The association between outdoor air pollution and stillbirths and low birthweight in the Czech Republic, where air pollution was high, was examined. METHODS: An ecological study was conducted, with routinely collected data on stillbirths and low birthweight (< 2500 g), air pollution (total suspended particulates, sulphur dioxide (SO2), and nitrogen oxides (NOx)), and socioeconomic factors (mean income, car ownership, divorce rate, etc). The analyses were restricted to 45 districts on which data on air pollution were available for the period 1986-8. The effects of exposure variables on frequency of pregnancy outcomes were estimated by logistic regression with district-years as the units of analysis. RESULTS: Stillbirth rate (4.2/1000 births in monitored districts) was not significantly associated with any indicator of air pollution, and was weakly related to mean income and proportion of births outside marriage. Crude prevalence of low birthweight (prevalence 5.5%) showed highly significant associations with several socioeconomic factors; after controlling for these, odds ratios (ORs)/50 micrograms/m3 increase in pollutant were: 1.04 (95% confidence interval (95% CI) 0.96 to 1.12) for total suspended particles, 1.10 (1.02 to 1.17) for SO2, and 1.07 (0.98 to 1.16) for NOx. When all pollutants were included in one model, SO2 remained related to low birthweight (OR 1.10 (1.01 to 1.20), p = 0.033). CONCLUSION: These results are consistent with a recent study in China where birthweight was also associated with total suspended particles and SO2 but ecological studies must be interpreted cautiously. Residual confounding by socioeconomic factors cannot be ruled out. The association between air pollution and birthweight requires further investigation. (+info)
Teratogenic response to arsenite during neurulation: relative sensitivities of C57BL/6J and SWV/Fnn mice and impact of the splotch allele.
(48/1902)
Arsenic is an environmental contaminant that induces congenital malformations, primarily neural tube defects, in laboratory animals, and it may contribute to human birth defects. The acute doses of arsenicals required to elicit teratogenesis in outbred strains of mice, however, are orders of magnitude higher than those to which humans are exposed environmentally. In order to examine interactions between arsenite administration during neurulation and murine genotype, the present study compares two inbred mouse strains, establishes a teratogenic dose of arsenite, and evaluates the effect of the splotch mutation on arsenic-induced teratogenesis. SWV/Fnn or C57BL/6J females were injected intraperitoneally with sodium arsenite (10 mg/kg) on days 6.5, 7.0, 7.5, 8.0, 8.5, or 9.0 of gestation. A dose-response study was carried out in the C57BL/6J strain, and the effect of the splotch mutation, introduced via the male (C57BL/6J Sp/+), was assessed. Fetuses were examined for external, visceral, and skeletal malformations. Fetuses from crosses of C57BL/6J females with C57BL/6J Sp/+ males were genotyped by PCR. Ten-mg/kg sodium arsenite was teratogenic in nearly 50% of C57BL/6J fetuses, and the C57BL/6J strain was significantly more sensitive to arsenite-induced embryo-lethality and teratogenicity than the SWV/Fnn strain. The spectrum of malformations produced was dependent on the gestational time point of arsenite administration. Introduction of the splotch allele significantly increased neural tube defects and other specific malformations. This result demonstrates that a mutation in a single gene can increase sensitivity to arsenic-induced birth defects. This murine study examines the interaction between arsenite-induced teratogenicity and genotype. (+info)