Infectious processes: an infrequent cause of first trimester spontaneous abortions

A systematic assessment of infections beginning early in pregnancyis necessary to determine the true role of infections in pregnancyloss, given that infections could readily arise only after fetaldemise. To this end, we have prospectively determined the frequencyof infections in pregnant women who were subjects in a multi-centreUS study. Insulin-dependent diabetic subjects and controlledsubjects were recruited either before conception (86%) or atthe latest within 21 days of conception (14%). We collecteddata prospectively on all important risk factors and potentialconfounding variables, seeing 386 diabetic subjects weekly and432 control subjects every other week during the first trimester.At each visit we inquired about untoward events and explicitlyabout fever or infections. We found no clinical evidence thatinfection occurred more often in the 116 subjects experiencingpregnancy loss as compared to the 702 having successful pregnancies.This held both for the 2 week interval in which a given losswas recognized clinically as well as in the prior 2 week interval.Similar findings were not only observed for both the controlas well as diabetic subjects but also when data were stratifiedby genital infection only or by systemic infection only. Ourprospective data suggest that the attributable risk of infectionin first trimester spontaneous abortion is small.     

Infectious diseases: Further evidence that infection is an infrequent cause of first trimester spontaneous abortion

A previous cohort study found no clinical evidence that infectionoccurred more often in subjects experiencing pregnancy losscompared with those experiencing success ful pregnancy [Simpsonet al (1996) Hum. Reprod., 11, 668—672]. Given these surprisingfindings, we conducted a similar analysis on another cohortalso followed prospectively. Using couples practising naturalfamily planning for conception or contraception, Informationon clinical evidence of infection was gathered beginning withweek 5 of gestation. Information on fever and signs of overtinfection was specilically sought by interview and physicalexamination. Frequencies of urinary, vaginal and other Infectionsin subjects experiencing pregnancy loss were 11.1, 9.5 and 8.7%respectively, not significantly different from rates in subjectshaving liveborns (10.1, 10.2 and 10.3% respectively). Thus,no association between clinical infection and early pregnancyloss (16 weeks) was observed. Cohort studies utilizing biologicallybased assays are awaited because extant data do not provideevidence that clinically evident infections play major rolesin first trimester pregnancy losses.     

In-vivo study of diazepam transfer across the first trimester human placenta

Diazepam transfer by the first trimester human placenta wasinvestigated at pregnancy termination between 6 and 12 weeksof gestation. Fetal fluid samples were obtained from the exocoelomicand amniotic cavities of 65 pregnancies between 8 and 25 minfollowing the i.v. administration of 0.1 mg/kg diazepam to themother. Diazepam was detected in one-third of coelomic fluidsamples and two-thirds of amniotic fluid samples. Maternal serumand urine diazepam concentrations correlated negatively andpositively respectively, with time from drug injection to sampling.Individual diazepam concentrations were low on the fetal side,and the corresponding concentrations were independent of maternalserum concentrations and the time from drug injection to sampling.Amniotic fluid diazepam content increased significantly withadvancing gestational age. A multiple regression analysis showedthat the diazepam content of the coelomic fluid was not influencedby maternal serum diazepam concentration, the time from druginjection to sampling or gestational age, whereas only gestationalage contributed to the diazepam content of amniotic fluid. Thesedata demonstrate that the placental transfer of diazepam occursfrom week 6 of gestation, indicate a preferential transfer ofthis drug to the amniotic cavity and suggest that diazepam mayaccumulate in fetal circulation and tissues during organo-genesis.     

Prevalence and distribution of chromosome abnormalities in a sample of first trimester internal abortions

Cytogenetic analysis was performed directly on villus from 202samples obtained at the evacuation of tbe uterine cavity incases of retained abortion in the first trimester, identifiedas such by ultrasound enamination. A precise delineation oftbe karyotype was obtained in 94% of the cases, while the efficiencyof karyotype analysis in samples of spontaneous abortion wasnot higher than 50%. An abnormal chromosome constitution wasfound in 145 fetuses (76.7%) of which 117, including mosaics,were aneuploid (70%), 16 polyploid (8.5%) and l2 had structuralabnormalities (6.3%). The relative proportion of chromosomeabnormalities in this material is higher than that found inspontaneous abortion for trisomies and double trisomies, butlower for 45,X and polyploidy. The method was found to be efficientin obtaining fetal karyotypes also in those cases in which thevillous material was scarce (1 mg), and thus it seems appropriatefor routine cytogenetic studies in the first trimester abortions.     

Relaxin concentrations in exoembryonic fluids during the first trimester

In 15 women undergoing therapeutic termination of pregnancy(8–13 weeks), the median concentration of relaxin was1000 ng/l in maternal serum, 122 ng/l in coelomic fluid and9 ng/l in amniotic fluid. Its presence in coelomic fluid suggeststhat relaxin may be present in the fetal circulation and thusbe able to influence embryonic development during the periodof organogenesis.     

Ultrasonographic detection of a live fetus in recurrent spontaneous abortion during the first trimester

To examine whether recurrent spontaneous abortion (RSA) canbe distinguished from repeated sporadic spontaneous abortion,the clinical course of 38 cases with three or more consecutiveand unexplained first trimester RSAs were retrospectively investigatedin this study. For comparison with controls, the clinical coursewas examined of 38 fertile females, who had had sporadic abortions.In 19 (50%) RSAs and 6 (16%) controls, fetal cardiac activitywas demonstrated by ultrasound during the course of pregnancy.The rate of detection of live fetus during pregnancy or at 8weeks ± 7 days gestation, was significantly greater inthe RSA group compared to the control. The rate of vaginal bleedingbefore spontaneous abortion was significantly less in the RSAgroup than in the control group. There was no difference betweenthe two groups in age or gestational age at spontaneous abortion.The patients with RSA were all examined for antiphospholipidantibodies in their sera and these were detected in eight ofthem. However, there was no difference in the rate of positivefetal cardiac activity between the RSA patients who tested positiveor negative for antibody. These results reveal that the clinicalcourse of RSA is very different from the course of sporadicabortion. Although sporadic abortion is a common complicationof pregnancy, RSA is not a random repeated abortion, but rathera separate disease from sporadic abortion in normal fertilefemales.     

Materno-fetal immunoglobulin transfer and passive immunity during the first trimester of human pregnancy

Passive transfer of immunity from the mother to the first trimesterfetus is of particular interest because of the reported highincidence of serious fetal sequelae due to congenital infection.We have examined the relationship between maternal serum, coelomicfluid and amniotic fluid concentrations of immunoglobulin (Ig)and complement. Ig fractions G (IgG), A (IgA), and M (IgM) andcomplement factors 3 (C3) and 4 (C4) were measured in 34 normalpregnancies between 6 and 12 weeks of gestation. The concentrationsof specific antibodies for Toxoplasma gondii, cytomegalovirus(CMV) and rubella were also measured on 21 matched samples fromthe same study group. IgG and IgA concentrations were detectedin all coelomic fluid samples whereas IgG was only measurablein two amniotic fluid samples. IgG and IgA concentrations wererespectively 28 and 128 times lower in coelomic fluid than inmaternal serum and probably reflect fetal serum concentrations.Significant positive linear correlations were found betweengestational age and the coelomic concentrations of IgG (P equals;0.001) and IgA (P = 0.014). There was no obvious associationbetween immunoglobulin concentrations in coelomic fluid andmaternal serum suggesting increasing active transport acrossthe placenta with advancing gestation. IgM, C3 and C4 were notdetected in coelomic or amniotic fluid samples. Specific antibodieswere found in 13 out of 63 samples of coelomic fluid and in32 out of 63 samples of maternal serum. They were found in coelomicfluid only if they were present in maternal serum. These resultssuggest that maternal IgG and IgA are potentially availableto the embryo as early as the 6th week of gestation. The presencein the coelomic fluid of the IgG fraction, both total and infectiousagent-specific transferred via the placenta, indicates thatthey may provide limited protection against congenital infectionin the first trimester.     

Fetal loss in the first trimester after demonstration of cardiac activity: relation of cytogenetic and ultrasound findings

A retrospective comparison of cytogenetic and ultrasound findingsin first trimester spontaneous fetal loss after demonstrationof cardiac activity was made. The crownrump length (CRL) wasmeasured twice for each fetus resulting in spontaneous abortion:(i) CRL was measured in the viable state while demonstratingcardiac activity, and the growth deviation was expressed asthe measured/ expected CRL ratio (M/E CRL ratio); (ii) in thesame fetus, CRL was measured after confirmation of fetal death,and designated as the post-mortem CRL. The chorionic tissuesof these abortuses were karyotyped. The CRL of fetuses whichresulted in normal deliveries were also measured as controls.As a result, 16 of 24 abortuses displayed an abnormal chromosomalanalysis (67%). Themean M/E CRL ratio of still-viable fetuseswas smaller than that of control fetuses (0.74 ± 0.20versus 0.98 ± 0.13 respectively, P < 0.01). The differencesin ratio between karyotypically normal and abnormal abortuseswere not statistically significant. The post-mortem CRL of deadfetuses was >20 mm in four of five monosomy X, two of three21-trisomy, one of three triploidy and none of eight embryoswith normal karyotype and five other trisomies. In conclusion,our study demonstrated that the M/E CRL ratio could be usedas a predictor of spontaneous abortions, although it does notdiscriminate abnormal karyotypes from normal ones. The embryoswith a post-mortem CRL more than 20 mm have a higher likelihoodof suffering monosomy X or 21-trisomy. The ultrasonographicfindings might offer a cytogenetic clue as to a possible causeto the developmental arrest.     

Progesterone receptor immunoreactivity at the maternofetal interface of first trimester pregnancy: a study of the trophoblast population

The aim of oar study was to localize oestrogen receptor (ER)and progesterone receptor (PR) in the trophoblast populationat the maternofetal interface in early pregnancy. Rat monoclonalantibodies to human ER and PR were used to study 44 cases ofchorionic villi and 82 cases of decidua using an immunocytochemicalmethod. The PR-immunoreactive products were localized in thenuclei of syncytiotrophoblast and cytotrophoblast cells of thevilli. Specific staining was also present in the cytoplasm.Villous stroma and vessels were stained occasionally. Usingcytokeratin staining in an adjacent section or double stainingwith PR and cytokeratin, the distribution of invading trophoblastcells and their PR expression were examined. In decidual stroma,a type of interstitial cell was identified which simultaneouslyexpressed cytokeratin and PR in the cytoplasm, indicating thatthe invading trophoblast cells may express PR. All extravillouspopulations at the interface were positive for PR, includingthe syncytial lining of the decidual surface, the cytotrophoblastcolumn, the cytotrophoblast shell and the interstitial trophoblast.The immunoreactivity of PR was also localized in the nucleiof vascular endothelial cells, whereas Factor VIII was localizedin the cytoplasm of the same cells, thus confirming their endothelialnature. In contrast to PR, little ER could be detected in thetrophoblast cell population using anti-ER antibody D75 in ourstudy.     

Pregnancy: The roles of oligomenorrhoea and fetal chromosomal abnormalities in spontaneous abortions

The pathogenesis of spontaneous abortions, other than fetalchromosomal abnormalities, is not fully understood. We examinedthe incidence of oligomenorrhoea in relation to fetal chromosomalanalyses and ultrasonographic examination in women who abortedspontaneously. The data demonstrated that the incidence of oligomenorrhoeawas higher in women with normal fetal karyotyped abortions,especially normal karyotyped anembryonic pregnancies, than inthose with abnormal karyotyped abortions (34.0 versus 12.5%,<italic>P</italic> <0.01). Furthermore, the incidenceof oligomenorrhoea was inversely correlated with fetal sizeexclusively in abortions with normal fetal karyotypes. It issuggested that oligomenorrhoea, i.e. delayed ovulation, itselfmay be closely associated with sporadic spontaneous abortion.     

Decidual vascularization and the expression of angiogenic growth factors and proteases in first trimester spontaneous abortions

BACKGROUND: Decidual vascular development is important for implantation.This study analysed decidual vascular adaptation to implantationin correlation with miscarriage in decidual secretory endometrium(DSE), decidua parietalis (DP) and decidua basalis (DB) of miscarriagepatients and matched controls. METHODS: Decidua was obtained during first trimester termination of pregnancy(controls) and vacuum aspiration in case of missed abortion(cases). Vascularization and the expression of VEGF-A, placentalgrowth factor, Flt-1, KDR, angiopoietin (Ang)-1, Ang-2, TIE-2,and membrane-type matrix metalloproteinases MT1-, MT2-, MT3-and MT5-MMP were determined at mRNA and protein level. Uterinenatural killer cells (CD56), macrophages (CD68), proliferation(Ki67) and apoptosis (activated caspase-3) were evaluated inconsecutive sections. RESULTS: Decidual vascularization showed differences between cases andcontrols, i.e. fewer vessels with larger circumference in cases.This correlated with the differential expressions of variousfactors at mRNA/antigen level and with increased endothelialflt1, KDR, MT2- and MT5-MMP expression in miscarriage patients.The differences between cases and controls were probably notbased on altered proliferation and/or apoptosis, since Ki67and active Caspase-3 showed comparable expression levels inboth groups. Although DB of cases and controls showed similaramounts of CD56- and CD68-positive cells, the case group didshow elevated levels of CD56 in DSE (P < 0.05) and of CD68in DP compared with the control group (P < 0.05). CONCLUSIONS: The differences in vascularization and in the expression ofangiogenic factors and proteases between groups suggest a correlationbetween decidual vascularization and the occurrence of miscarriages.     

Variations of the Amnionless gene in recurrent spontaneous abortions

Recurrent spontaneous abortions (RSA) are estimated to affect 0.5-1% of couples trying to have a child. The causes of RSA are unknown in the majority of cases. This study aimed to determine whether homozygous mutations in the AMN gene in a fetus cause spontaneous abortions in humans, as they are known to cause spontaneous abortions in mice. The study was conducted by screening 40 couples and 5 women with three or more unexplained spontaneous abortions for heterozygous mutations in the AMN gene using denaturing high-performance liquid chromatography. Altogether, 3 exonic and 11 intronic sequence variations were found. There were no significant differences in the frequencies of the variations between the patients and a control group. One of the exonic variations was non-synonymous, and three of the variations may affect gene splicing. None of the putative phenotype-affecting variations were found in both partners in any couple. These results indicate that RSA in the couples studied cannot be explained by homozygous AMN mutations in the fetus. However, two couples had different, potentially deleterious variations in both partners. If these variations have a phenotypic effect, the RSA experienced by these couples may be caused by mutations in the AMN gene. In addition, birthplaces of the patients' ancestors revealed some clustering, suggesting that some patients may carry a founder mutation in another gene which may contribute to RSA.     

反复性自然流产患者MTHFR基因的多态性研究

目的检测反复性自然流产（recurrent spontaneous abortion，RSA）≥2次患者亚甲基四氢叶酸还原酶（methylenetetmhydrofolate reductase，MTHFR）基因位点C677T的出现频率，分析其与RSA发生的可能关系。方法采用聚合酶链反应-限制性片段长度多态（PCR—RFLP）技术检测80例RSA患者和60例正常妇女MTHFR基因C677T位点的分布和频率。结果在MTHFR基因突变分型中，RSA组T／T型以及C／T＋T／T型出现频率显著高于对照组。对照组C／C型频率显著高于患者组；单纯C／T型两组没有显著性差异。结论MTHFR基因位点突变以及部分HLA—DR基因位点与RSA发生有关。     

Chromosome analysis in 100 cases of first trimester trophoblast sampling

The cytogenetic findings in 20 experimental and 80 diagnostic cases of first trimester trophoblast biopsy are presented. All samples were obtained between the 8th and 13th week of gestation with the direct vision, trans-cervical technique. Except when fetal sexing because of X-linked disease was the issue, long-term culture with in situ preparation was the method routinely employed in processing the biopsies for cytogenetic analysis. In 78 of the 80 clinical cases and in all reported experimental cases we were successful in establishing a karyotype from the sampled tissue. Unbalanced karyotypes were found in two experimental and six clinical cases. Tetraploidy was found in one clinical case, but was not confirmed in subsequently sampled amniotic fluid cells. In another clinical case, we were unable to confirm in the aborted placenta the trisomy 18 found in the trophoblast biopsy. In the rest of the induced abortions in the clinical series, the karyotype arrived at prenatally has been confirmed, and the 27 babies so far born have been healthy and with phenotypic sex corresponding to the prenatal findings. Six women have miscarried after sampling; in one of these cases the fetus had the karyotype 47,XX, + 13.     

Expectant, medical or surgical treatment for spontaneous abortion in first trimester of pregnancy: a cost analysis

BACKGROUND: Misoprostol and expectant care have been shown to be acceptable alternatives to routine surgical evacuation for treatment of spontaneous abortion in the first trimester of pregnancy. The objective of this study was to analyse the cost of expectant care, misoprostol therapy and surgical evacuation. METHODS: A decision tree was designed to simulate the clinical outcome and health care resource utilization of surgical evacuation, misoprostol and expectant care for patients presenting with uncomplicated spontaneous abortion in the first trimester of pregnancy. Clinical inputs were estimated from literature and the cost analysis was conducted from the perspective of a public health care provider in Hong Kong. RESULTS: The base-case analysis showed that the misoprostol group (1000 US dollars per patient) was the least costly alternative, followed by the expectant care (1172 US dollars per patient) and surgical evacuation (2007 US dollars per patient). Rates of complete abortion using misoprostol and expectant care were identified as influential factors. Monte Carlo simulation (10000 cohorts) showed that the misoprostol and the expectant care groups were less costly than the surgical evacuation group 100 and 88% of the time. The misoprostol group was less costly than the expectant group 100% of the time. CONCLUSIONS: Misoprostol therapy appears to be the least costly approach for treatment of uncomplicated spontaneous abortion.     

Expression of kisspeptin/GPR54 and PIBF/PR in the first trimester trophoblast and decidua of women with recurrent spontaneous abortion

Kisspeptin and its receptor GPR54 play a major role in trophoblast invasion, and progesterone-induced blocking factor (PIBF) is needed for maintaining pregnancy. The expression of kisspeptin/GPR54 and PIBF/progesterone receptor (PR) in trophoblasts and deciduas and the relationship between kisspeptin and PIBF were investigated in the same women with recurrent spontaneous abortion (RSA). Trophoblastic and decidual tissues were collected from 32 RSA women who miscarried a genetically normal fetus, and 35 women who had voluntary abortion. Kisspeptin, GPR54, PIBF and PR were investigated using immunohistochemistry. Kisspeptin, GPR54 and PIBF expressions in syncytiotrophoblasts and cytotrophoblasts were decreased in RSA women as compared to controls (P < 0.05). Kisspeptin, PIBF and PR expressions in deciduas were significantly decreased in RSA women as compared to controls (P < 0.01). GPR54 expression in deciduas nearly showed no difference between the RSA group and the control group (P = 0.958). Kisspeptin and PIBF expressions in syncytiotrophoblasts, cytotrophoblasts and deciduas were correlated with each other in the RSA group (Kappa = 0.602, P = 0.001; Kappa = 0.590, P = 0.001; Kappa = 0.392, P = 0.011). These data support the hypothesis that decreased kisspeptin and PIBF expressions in trophoblasts and deciduas are associated with RSA.     

Placenta percreta-induced uterine rupture diagnosed by laparoscopy in the first trimester

Spontaneous uterine rupture is lethal in pregnant women. Placenta percreta-induced spontaneous uterine rupture in the first trimester is extremely rare and difficult to diagnose. A 35-year-old pregnant woman, with a history of 2 vaginal deliveries and 2 spontaneous abortions treated by dilatation and curettage, was admitted to the emergency department because of sudden severe abdominal pain; the gestational age as calculated by sonography was 14 weeks. Diagnostic laparoscopy was considered for surgical abdomen and fluid collection that was noted in sonography. During laparoscopy, uterine rupture with massive bleeding was detected; therefore, total abdominal hysterectomy was performed. The patient was discharged without any complications. Pathological analysis of the uterine specimen revealed placenta percreta to be the cause of the rupture. Uterine rupture should be considered in the differential diagnosis in all pregnant women who present with acute abdomen, show fluid collection in the peritoneal cavity. In addition, we recommend laparoscopy for the investigation of acute abdomen with unclear diagnosis in the first trimester of pregnancy.     

Pregnancy: Bereavement, grieving and psychological morbidity after first trimester spontaneous abortion: comparing expectant management with surgical evacuation

Early pregnancy loss is a profound adverse life event for manywomen, and increased psychiatric morbidity has been shown tooccur after spontaneous abortion. Dilatation and curettage (D&C)has been the cornerstone in the treatment of first trimesterspontaneous abortion over the last few decades. During recentyears the possibility of conservative management has, however,been increasingly discussed. In a prospective randomized trial,we compared psychological reactions and morbidity, after eitherexpect ant management or D&C, for miscarriages of <13weeks gestation In which a transvaginal ultrasound examinationshowed Intrauterine tissue and/or blood clots with an antero-posteriordiameter of between 15 and 50 mm. Of the 86 patients included,58 were randomized to expectant management and 28 to primaryD&C. In patients randomized to expectant management, pregnancyproducts shown by transvaginal ultrasound disappeared within3 days in 43 cases (74%), whereas 15 patients (26%) underwentD&C owing to retained products of conception after 3 days.At 2 weeks after indusion, all patients answered self-administeredquestionnaires, induding visual analogue scales, concerningtheir experience of the pregnancy loss, the present situationand concerns about the future. A brief anxiety status inventorywas included. This study showed no increase in anxiety or depressivereactions 2 weeks after a first trimester spontaneous abortionwhen these patients were compared with non-pregnant healthyworking females 19–39 years of age. Moreover, there wereno significant differences in psychological reactions betweenpatients managed either expectantly or by D&C.     

Intra- and inter-observer variation in the interpretation of histological features suggesting chromosomal abnormality in early abortion specimens

Early spontaneous abortion is a common phenomenon, with more than 50% of early cases showing chromosomal abnormalities. We have undertaken a study to evaluate intra- and inter-observer reproducibility of histological diagnoses of features associated with chromosomal abnormalities, such as chorionic villus size, shape, vascularity, trophoblastic proliferation and trophoblastic pseudo-inclusions. The intra-observer variation for most histological features was small. However, the agreement beyond chance between two or more observers in judging histomorphological features of early abortion placentae only reached clinically relevant values for size and shape of the chorionic villi and for the number of trophoblastic pseudo-inclusions.