Amniotic fluid concentrations of dimeric inhibins, activin A and follistatin in pregnancy

OBJECTIVE: The feto-placental unit is the major source of circulating concentrations of inhibin A and activin A in human pregnancy. The aim of this study was to measure the amniotic fluid concentrations of inhibin A, inhibin B, activin A and follistatin in pregnancies bearing male and female fetuses. DESIGN AND METHOD: Amniotic fluid samples collected by amniocentesis were stored at -20 degrees C. Dimeric inhibins, 'total' activin A and 'total' follistatin were measured using specific two-site enzyme immunoassays. Samples were assayed blindly and the information on fetal sex was obtained from the cytogenetics laboratory. RESULTS: Data show that amniotic fluid concentrations of inhibin A, inhibin B and activin A gradually increase with gestation whilst concentrations of follistatin are similar between weeks 15 and 20 of pregnancy. Mean amniotic fluid levels of inhibin A and inhibin B at 16 and 17 weeks gestation and mean activin A levels at 15 and 16 weeks gestation are considerably lower in pregnancies with male (n=24) compared with female (n=28) fetuses. Levels of follistatin are not different in the male and female fetal pregnancies at any studied gestation. CONCLUSIONS: The results indicate that amniotic fluid contains high concentrations of inhibins (A and B), activin A and follistatin in early pregnancy suggesting that these hormones are produced by the fetal membranes and may be involved in the development of the fetus.     

Reliable prenatal diagnosis of Canavan disease (aspartoacylase deficiency): Comparison of enzymatic and metabolite analysis

Summary Prenatal diagnosis has been undertaken in 17 pregnancies in 15 families at risk for aspartoacylase deficiency. Amniocentesis was at 14–18 weeks gestation followed by measurement of amniotic fluidN-acetyl-l-aspartate (NAA) levels in all pregnancies and amniocyte aspartoacylase activity in most pregnancies. In one case amniocentesis was performed at 11 weeks gestation in conjunction with chorionic villus sampling. At 14–18 weeks of gestation, control levels of NAA were 0.30–2.55 µmol/L. The fetus was predicted to be affected in 8 of the pregnancies, 4 of which were confirmed by enzyme analysis on fetal tissue and 2 by the clinical and metabolic expression of Canavan disease in a newborn. In two cases there was no fetal tissue available for enzyme confirmation. One of these had the highest amniotic fluid NAA level (8.68 µmol/L) and in the other pregnancy there were two amniocenteses, both with markedly elevated levels. Of 9 fetuses predicted to be normal, 8 newborns were clinically and biochemically normal. A single case with amniotic fluid NAA in the normal range (1.56 µmol/L, measured in one laboratory only) resulted in an aborted fetus in whom aspartoacylase was deficient in cultured skin fibroblasts. We propose that amniotic fluid NAA levels remain the best predictor of an affected fetus and recommend that the assay be performed in multiple laboratories.     

KINETICS OF PLASMA CORTICOSTEROIDS DURING METYRAPONE INFUSION IN MAN

The effect of metyrapone on plasma kinetics of cortisol (F), 11-deoxycortisol (S), corticosterone (B), 11-deoxycorticosterone (DOC), aldosterone (Aldo) and 17 hydroxyprogesterone (17 OHP) was studied in ten normal prepubertal children intravenously infused with the drug (1 gm/1.73 m2 body surface area in 4 h). Similar falls in F, B and Aldo were observed during the first hour expressing similar sensitivity of the 11 hydroxylases to the drug. The effect of the compensatory increase of endogenous ACTH could be detected after 1 hour by the rise in 17 OHP. However the concentrations of the 11-hydroxy compounds, F, B and Aldo, remained low throughout the infusion period. From the second hour onwards, facilitation of the synthesis of DOC was noticed. After the end of infusion, the levels of the precursors decreased and F and B were restored to initial values. Aldo remained low probably due to the inhibitory effect of the elevated DOC on the renin-angiotensin system.     

Daily hormonal changes in the maternal, fetal, and amniotic fluid compartments before parturition in a primate species

The daily hormonal fluctuations that occur simultaneously in the fetus, mother, and amniotic fluid during late gestation and before preterm parturition were studied in long term catheterized rhesus macaques. Blood and amniotic fluid samples were collected twice daily and analyzed by RIA for estrone, estradiol, dehydroepiandrosterone sulfate (DHEAS), progesterone, cortisol, and prostaglandin F2 alpha metabolite (PGFM). Vaginal delivery in monkeys with live fetuses was preceded by rising concentrations of DHEAS in fetal, but not maternal, blood. Parallel increases in fetal plasma estrone, maternal plasma estrone and estradiol, and amniotic fluid estrone preceded the rise in amniotic fluid PGFM (P less than 0.005, by analysis of variance). Cortisol levels remained stable in maternal blood and amniotic fluid, but increased before delivery in fetal blood. Nocturnal progesterone peaks in both fetal and maternal blood increased progressively in magnitude in fetuses before parturition. Rising concentrations of fetal DHEAS, estrone, and progesterone indicated an increase in adrenal activity before parturition in the rhesus fetus. PG production, reflected in amniotic fluid PGFM concentrations, was temporally related to increasing amniotic fluid concentrations of estrone. Although progesterone withdrawal may occur at a local tissue level, parturition occurred without an apparent decrease in circulating maternal, circulating fetal, or amniotic fluid progesterone concentrations.     

Prenatal diagnostic and prognostic value of human cytomegalovirus load and IgM antibody response in blood of congenitally infected fetuses

Human cytomegalovirus (HCMV) load and virus-specific IgM were quantified in blood of 36 fetuses from mothers with primary HCMV infection. Nineteen fetuses were congenitally infected and 17 were uninfected as diagnosed by virus isolation from and DNA detection in amniotic fluid. Sensitivity of antigenemia was 57.9%; of viremia, 55. 5%; of leukoDNAemia, 82.3%; and of IgM, 57.9%; specificity was 100% for all assays. When amniocentesis was performed, 4 HCMV-infected fetuses (group A) showed abnormal ultrasound and biochemical/hematologic findings, 8 (group B) had elevated gamma-glutamyl transferase values, and 7 (group C) had normal ultrasound and biochemical findings. Virus loads were higher in groups A and B than in group C. In group A, no pregnancy went to term, in group B, 3 of 6 newborns were symptomatic at birth, and in group C, the 6 newborns were subclinically infected. Taken together, virologic, laboratory, and ultrasound findings may contribute to a better prognostic definition of fetal HCMV infection.     

Maternal side effects of prenatal dexamethasone therapy for fetal congenital adrenal hyperplasia.

Prenatal treatment of virilizing congenital adrenal hyperplasia in female fetuses via maternal dexamethasone (Dex) therapy (1-1.5 mg/day) from first trimester to birth was associated with excessive weight gain (47-56 pounds at 35-37 weeks gestation), Cushingoid facial features, severe striae resulting in permanent scarring, and hyperglycemic response (8-11.7 nmol/L) to oral glucose administration in all our experience (three cases). Other symptoms included hypertension, gastrointestinal intolerance, or extreme irritability. Previous pregnancies were uncomplicated by these problems. In each case, first or second trimester amniotic fluid 17-hydroxyprogesterone (17OHP, 17-41 nmol/L; normal less than 0.4 nmol/L), androstenedione (22-31 nmol/L, normal less than 5 nmol/L), and testosterone levels (0.54-0.7 nmol/L, normal less than 0.4 nmol/L) during Dex treatment were elevated regardless of the newborn genital outcome. Maternal serum estriol (E3) levels in one mother (normal newborn genitalia) were consistently low (less than 0.2 nmol/L) during the second and third trimester. In two mothers (partially virilized newborn genitalia) initial second trimester E3 levels were unsuppressed (11, 17.4 nmol/L) and suppressed (less than 1.4 nmol/L) following short-term increased dose. Conclusion: prenatal Dex treatment of virilizing congenital adrenal hyperplasia at a dose of 1-1.5 mg daily throughout gestation is associated with significant maternal side effects. Parents should be informed of these side effects before initiation of treatment. Careful monitoring for signs of side effects, medical intervention when necessary, and lowering of Dex dose during the second half of gestation would minimize the side effects. Maternal serum E3 levels appear useful for prediction of fetal outcome while amniotic fluid steroid levels may not.     

Thrombopoietin levels in cord blood plasma and amniotic fluid in fetuses with alloimmune thrombocytopenia and healthy controls

To extend our knowledge of the kinetics of fetal thrombopoietin (TPO), we studied TPO levels in cord blood plasma and amniotic fluid collected from 15 fetuses considered to be at risk of fetomaternal alloimmune thrombocytopenia and also from 10 healthy controls at caesarean delivery. In the plasma of all 25 fetuses and newborn infants studied, TPO was detected above the lower limit of detection (7 pg/ml) and correlated inversely with platelet counts (r = -0.53, P = 0.006). At term, TPO detected in amniotic fluid was at significantly lower levels (7 pg/ml; range 0-22 pg/ml) than simultaneously obtained cord plasma TPO (114 pg/ml; range 43-201 pg/ml; P < 0.001). There was no correlation between levels of TPO in amniotic fluid and cord plasma or platelet counts. In the serial samples collected from the five fetuses with HPA-1a alloimmunization before 37 weeks' gestation, the TPO levels in amniotic fluid were significantly higher than at term (P = 0.013): from 22 to 28 weeks' gestation, 42 pg/ml (30-78 pg/ml); from 32 weeks', 24 pg/ml (17-33 pg/ml); at term, 8 pg/ml (4-13 pg/ml), correlating inversely with gestational age (r = -0.81, P = 0.003). Thus, TPO is present in amniotic fluid at levels apparently inversely related to gestational age. Whether these high levels seen early in pregnancy are normal or are associated with the HPA-1 alloimmunization remains to be shown.     

Profiling steroid hormones in amniotic fluid of midpregnancy by routine stable isotope dilution/gas chromatography-mass spectrometry: reference values and concentrations in fetuses at risk for 21-hydroxylase deficiency.

Using routine stable isotope dilution/gas chromatography-mass spectrometry, 17-hydroxyprogesterone, androstenedione, testosterone, dehydroepiandrosterone, androstanediol, and 5alpha-dihydrotestosterone have been profiled in amniotic fluid of midgestation in 77 normal fetuses and 38 untreated or dexamethasone-treated fetuses at risk for 21-hydroxylase deficiency. Dexamethasone was suspended 5-7 days before amniocentesis. In normal fetuses, amniotic fluid concentrations (median, range; nanograms per mL) of 17-hydroxyprogesterone did not reveal a sex difference (1.48, 0.21-4.96), whereas those of androstenedione were lower in females (0.53, 0.00-2.71) than in males (0.93, 0.29-1.98). Testosterone levels were higher in males (0.24, 0.00-0.50) than in females (0.00, 0.00-0.27). No sex difference was found for dehydroepiandrosterone (0.47, 0.19-1.77). Levels of androstanediol and 5alpha-dihydrotestosterone were below the detection limit of our method in most cases. Regarding prenatal diagnosis of 21-hydroxylase deficiency, 17-hydroxyprogesterone and androstenedione presented the diagnostically most valuable steroids and were of equal diagnostic potential. They permitted successful diagnosis in 36 of 37 fetuses at risk: 12 were untreated and unaffected, 13 were treated and unaffected, 4 were untreated and affected (3 salt wasters and 1 simple virilizer), and 8 were treated and affected (5 salt wasters and 3 simple virilizers). In the latter group, one simple virilizer revealed normal steroid concentrations. Isotope dilution/gas chromatography-mass spectrometry, providing the highest specificity in steroid analysis, is proposed for routine use in clinical steroid analysis whenever maximal reliability is requested. Our study provides the first mass spectrometric reference data on amniotic fluid steroid concentrations and underscores the high accuracy of prenatal hormonal diagnosis of 21-hydroxylase deficiency.     

11 Beta-hydroxylase deficiency congenital adrenal hyperplasia: update of prenatal diagnosis

Hormonal measurements in maternal urine and amniotic fluid (AF) during pregnancy and/or at delivery correctly predicted the postnatal diagnosis of 11 beta-hydroxylase deficiency congenital adrenal hyperplasia (11 beta-OH deficiency CAH) in 7 fetuses at risk. In the 4 affected ones, maternal urinary tetrahydro-11-deoxycortisol (THS) excretion was high during the first trimester [0.3-2.2 mg/day (1.1-7.7 mumol/day)] and rose further during the third trimester [0.5-3.5 mg/day (1.8-12.3 mumol/day)] compared to urinary THS excretion in 20 normal pregnancies of the same gestational age (P less than 0.01). In 1 mother, dexamethasone administration (2 mg/day for 72 h) greatly reduced urinary THS excretion (and plasma steroid levels). Urinary THS excretion was low after delivery in these mothers, in normal pregnancies, and in parents of affected individuals [less than 0.05 mg/day (less than 0.08 mumol/day); P = NS]. However, 2 of the 3 heterozygous mothers who carried nonaffected fetuses excreted moderately increased amounts of THS during pregnancy, ranging from 0.15-0.26 mg/day (0.53-0.91 mumol/day), significantly higher than normal (P less than 0.01). Although urinary THS excretion in these mothers was similar to that in 2 mothers with affected fetuses early in pregnancy, urinary THS excretion was higher in mothers with affected compared to those with nonaffected fetuses after the first trimester (P less than 0.01). AF THS and 11-deoxycortisol concentrations were markedly elevated in pregnancies with affected fetuses (P less than 0.01), but normal in nonaffected ones. AF delta 4-androstenedione levels were high in 2 pregnancies and borderline elevated in a third. Although the AF tetrahydrocortisol and tetrahydrocortisone levels were always within the normal range, the AF THS to tetrahydrocortisol plus tetrahydrocortisone ratio was significantly elevated in all pregnancies with affected fetuses (2.8-5.5; P less than 0.01) and normal in nonaffected ones (0.48-1.2; P = NS) compared to that in 160 normal pregnancies [0.64 +/- 0.34 (+/- SD)]. AF 17-hydroxyprogesterone, testosterone, and 11-deoxycorticosterone levels were normal in all pregnancies. Maternal plasma 11-deoxycortisol and delta 4-androstenedione concentrations, determined sequentially throughout gestation, were variable and did not contribute to prenatal diagnosis. All affected infants were born hyperpigmented, 2 were large for gestational age, and the female was severely virilized. In the first week of life 2 males developed severe hypertension with seizures and adrenal insufficiency, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)     

Factor IX and prothrombin in amniotic fluid and fetal plasma: constraints on prenatal diagnosis of hemophilia B and evidence of proteolysis

Potential limitations of prenatal diagnosis of hemophilia B, as compared to hemophilia A, include (1) occurrence of far more frequent defects with abnormal circulating antigen, (2) lower levels of factor IX in fetal plasma at 16 to 20 weeks gestation, and (3) the presence of factor IX antigen in amniotic fluid. In addition, proteolysis could occur, especially with amniotic fluid contamination of fetal plasma. A sensitive polyclonal immunoradiometric assay for factor IX antigen was used to characterize the range of levels in amniotic fluids and fetal plasma samples. To assess for altered forms, factor IX species were compared to those of a homologous clotting factor, prothrombin. Fourteen postmortem abortus blood samples from fetuses of 14 to 23 weeks gestation had factor IX antigen levels that averaged 5.1 U/dL and ranged from 1.7 to 15 U/dL. Amniotic fluid factor IX antigen averaged 2.9 U/dL, with a range from 1.4 to 8.5 U/dL in 19 separate amniocentesis samples. Thus, in a male fetus at risk of hemophilia B and with a low circulating level of gene product, mixture of fetal plasma with amniotic fluid could severely limit prenatal diagnosis, assuming that the amniotic fluid factor IX is of maternal origin. Despite rapid processing of amniotic fluid samples, the prothrombin was extensively cleaved, suggesting that it had been activated in vivo. On gel electrophoresis of amniotic fluid samples, however, factor IX was only minimally cleaved. In the postmortem fetal blood specimens, prothrombin was partially cleaved. On crossed-immunoelectrophoresis, fetal plasma prothrombin showed decreased migration in calcium, compared to EDTA, indicative of mature gamma-glutamyl carboxylation. The latter presumably resulted from fetal hepatic synthesis.     

Comparison of CD8+ T Cell responses to cytomegalovirus between human fetuses and their transmitter mothers

BACKGROUND: The mechanisms responsible for the increased susceptibility of fetuses to cytomegalovirus (CMV) were studied by comparing CD8(+) T cell responses to the virus in susceptible fetuses to those in their comparatively more resistant mothers. METHODS: Included in the study were 16 transmitter mothers who underwent seroconversion during the first trimester of pregnancy as well as their fetuses, who were positive for CMV in amniotic fluid by polymerase chain reaction at 17-19 weeks of gestation. Fetal and maternal blood samples were collected between the 22nd and 39th week of gestation. Cytotoxic T lymphocytes (CTLs) that had activated (HLA-DR(+)), effector/memory (CD28(-)), and memory (CD18(high)) phenotypes; that stained with the HLA-A2/pp65 or the HLA-B7/pp65 multimer; and that secreted interferon (IFN)- gamma were enumerated by flow cytometry. Viral loads were determined simultaneously. RESULTS: The results showed (1) similar levels of activated, effector/memory, and memory CTLs in fetuses and mothers but a smaller pp65-specific CTL pool in fetuses (median, 0.015% vs. 0.99%; P=.003); (2) similar percentages of CTLs secreting IFN- gamma after stimulation with ionomycin/phorbol myristate acetate in fetuses and mothers but lower percentages of CTLs secreting IFN- gamma after stimulation with a CD3 monoclonal antibody in fetuses (median, 1% vs. 14%; P=.01); and (3) higher viral loads (mean, 17,290 vs. <250 genome equivalents/mL) in fetuses. CONCLUSION: Impaired viral clearance might be related to a defective expansion of the pp65-specific CTL pool and/or to the immaturity of IFN- gamma -secreting cells in fetuses.     

Ontogeny of foetal exposure to maternal cortisol using midtrimester amniotic fluid as a biomarker

OBJECTIVE: There is increasing evidence that antenatal stress has long-lasting effects on child development, but there is less accord on the mechanisms and the gestational window of susceptibility. One possible mechanism is by foetal exposure to maternal cortisol. To explore this, we investigated the relationship between cortisol in maternal plasma and amniotic fluid, and any moderating influence of gestational age. PATIENTS AND MEASUREMENTS: Two hundred and sixty-seven women awaiting amniocentesis for karyotyping were studied. Samples were collected between 0900 and 1730 h. Gestational age was determined to the nearest day by ultrasound biometry and time of collection noted to the nearest 15 min. Total cortisol was measured by radioimmunoassay in paired amniotic fluid and maternal blood samples (n = 267) [gestation range 15-37 weeks, median 17 weeks (119 days)]. RESULTS: Both maternal and amniotic fluid cortisol levels increased with gestation (r = 0.25, P < 0.001; r = 0.33 P < 0.001, respectively). Amniotic fluid cortisol was positively correlated with time of collection (r = 0.22, P < 0.001) and negatively with maternal age (r =-0.24, P < 0.001). There was a positive correlation between amniotic fluid cortisol with maternal plasma levels (r = 0.32, P < 0.001), which persisted after multivariate analysis controlling for gestation, time of collection and maternal age. The association appeared to be dependent on gestational age, being nonsignificant at 15-16 weeks' gestation and increasing in strength thereafter. CONCLUSION: This study shows a positive correlation between maternal and amniotic fluid cortisol levels, which becomes robust from 17 to 18 weeks onwards. The results provide support for the hypothesis that alterations in maternal cortisol may be reflected in amniotic fluid levels from this gestation.     

Human cytomegalovirus (HCMV) DNAemia in the mother at amniocentesis as a risk factor for iatrogenic HCMV infection of the fetus

To investigate whether invasive procedures performed in the presence of human cytomegalovirus (HCMV) DNA in maternal peripheral blood (HCMV DNAemia) represent a risk for iatrogenic transmission of HCMV infection to the fetus, 194 pregnant women undergoing prenatal diagnosis because of a primary HCMV infection and their 199 fetuses were investigated. Overall, 27 (37%) of 73 mothers of uninfected fetuses and 22 (37%) of 59 mothers of infected fetuses were HCMV DNAemia-positive at amniocentesis. Of the 8 mothers of the 8 fetuses with false-negative amniocentesis results, 4 were DNAemia-positive and 4 were DNAemia-negative at amniocentesis. Therefore, maternal HCMV DNAemia is not a significant risk factor for iatrogenic HCMV transmission to the fetus during amniocentesis.     

Detection of house-dust-mite allergen in amniotic fluid and umbilical-cord blood

Mononuclear cells in umbilical-cord blood display allergen-specific reactivity, but how allergen exposure occurs in utero is unknown. We investigated the presence of a common inhalant allergen (Der p 1), to which mothers are exposed throughout pregnancy, by ELISA in matched maternal blood and amniotic fluid samples at 16-17 weeks of gestation, and in matched maternal and umbilical-cord blood at term (> or =37 weeks of gestation). Der p 1 was detectable in 24 of 43 amniotic fluid samples where it was also present in maternal blood, and in 15 of 24 cord-plasma samples at significantly higher concentrations than in the maternal plasma (p=0.022). The detection of Der p 1 in the amniotic fluid and the fetal circulation provides direct evidence of transamniotic and transplacental allergen exposure.     

ALPHA-FETOPROTEIN IN THE ANTENATAL DIAGNOSIS OF ANENCEPHALY AND SPINA BIFIDA

α-fetoprotein (A.F.P.) has been measured in the amniotic fluids of thirty-one pregnancies leading to anencephaly (or anencephaly and spina bifida), three leading to spina bifida, and three leading to hydrocephaly (or hydrocephaly and spina bifida). In the anencephalic cases all A.F.P. concentrations were well above the normal range between 25 and 35 weeks of gestation; after 35 weeks five out of nine cases were clearly above normal. In a single case of spina bifida, where amniotic fluid was obtained at 13 weeks, A.F.P. concentration was four times greater than the highest normal level. After 30 weeks' gestation amniotic fluids from pregnancies leading to spina bifida and hydrocephaly could not be distinguished from normal pregnancies. These results suggest that amniotic-fluid-A.F.P. measurements will be valuable in the early antenatal diagnosis of anencephaly and spina bifida and will enable termination of these pregnancies.     

Successful prenatal molecular diagnosis of carbamyl-phosphate synthetase I deficiency in two at-risk pregnancies

Summary We report the two first prenatal diagnoses in an Italian family with a proband affected by neonatal carbamyl-phosphate synthetase I deficiency in which molecular analysis identified V457G and Q810R amino acid substitutions. We performed a prenatal diagnosis on genomic DNA isolated from chorionic villus and amniotic fluid samples collected at 13 weeks of gestation. In the first pregnacy, the fetus was compound heterozygous for the mutations and termination of pregnancy was elected. The genetic lesions were also confirmed on genomic DNA isolated from the fetus’s liver and skin fibroblasts. A few months later, we performed a second prenatal diagnosis in this family. The second fetus was heterozygous for the wild-type alleles. The pregnancy was continued and a girl was born at 41 weeks of gestation. We have confirmed the wild-type state on the baby’s DNA.     

Virilization without adrenal hyperplasia in 21-hydroxylase deficiency during fetal life

The characteristic excess production of androgens in the cortisol 21-hydroxylase defect is generally considered to be secondary to ACTH stimulation of alternate pathways. Whenever a morphological examination of the adrenals has been possible in this disorder, adrenocortical hyperplasia was a constant finding. The availability of methods for the prenatal diagnosis of the 21-hydroxylase defect has made it possible to examine some of the manifestations of this disorder during fetal life. We studied a severely virilized 20-week-old aborted female fetus with the 21-hydroxylase defect whose adrenals were neither grossly enlarged nor microscopically hyperplastic. In a pregnancy at risk for congenital adrenal hyperplasia due to a 21-hydroxylase deficiency, amniocentesis was performed in the 18th week of gestation. The 21-hydroxylase defect was established by HLA typing and highly elevated levels of 17-hydroxyprogesterone, testosterone, and androstendione in amniotic fluid. After counselling, the parents, who already had a girl with the salt-wasting form of 21-hydroxylase deficiency, wished termination of the pregnancy. The aborted 20-week-old fetus was within the normal range for gestational age in weight and height. The external genitalia were ambiguous and extremely virilized, with an enlarged clitoris and fused labioscrotal folds. A urogenital sinus opened at the base of the clitoris. The internal organs were female, with a normal uterus and ovaries. Both adrenals were normal in size and weight for their gestational age. Histological examination of the adrenals revealed no abnormalities, and no hyperplasia was detectable. Thus, the adrenals in the 21-hydroxylase defect during fetal life secrete excessive amounts of androgens and cause virilization in the absence of adrenocortical hyperplasia.     

Corpus luteum and fetoplacental functions in monkeys hypophysectomized during late pregnancy.

The hormonal regulation of corpus luteum (CL) function during late pregnancy was studied in hypophysectomized monkeys. Between days 149-154 of gestation, 9 days after hypophysectomy, progesterone in the uteroovarian vein (UOV), uterine vein (UV) and peripheral circulation (P) averaged 179.7 ng/ml, 38.9 ng/ml and 5.5 ng/ml, respectively. Amniotic fluid prolactin ranged from 2150-6700 ng/ml and monkey chorionic somatomammotropin (mCS) in mothers carrying live fetuses ranged from 11.4-30.8 micrograms/ml in the UV and P. Prolactin and monkey chorionic gonadotropin in the UV and P were low or nondetectable as was mCS in 2 mothers carrying dead fetuses. CL function was further studied 7 and 39 days after removal of the fetus alone or both the fetus and placenta. Placental delivery was extremely variable, ranging from 2-greater than 63 days post-fetectomy. Although progesterone was not detectable in the P7 days after cesarean section in those animals in which both fetus and placenta were absent, surprisingly, progesterone was measurable in the UOV (range 1.6-48.2 ng/ml). At 39 days, progesterone was either nondetectable or very low. We have interpreted these data to mean: 1) neither the maternal pituitary gland nor a live fetus is necessary for placental or corpus luteum production of progesterone during late pregnancy, 2) the presence of high levels of circulating prolactin and mCS are apparently not necessary for continued secretion of progesterone from the CL during late pregnancy, 3) the fetoplacental unit may be the source of the luteotropic stimulus of late pregnancy since progesterone in the UOV decreases markedly in the absence of the fetoplacental unit or disruption of the unit brought about by fetectomy, and 4) regression of the CL following cesarean section in hypophysectomized monkeys is exceedingly slow when compared to the precipitous regression characteristic of the CL of the nonfertile menstrual cycle.     

Evolution of steroids during pregnancy: Maternal,placental and fetal synthesis

Progesterone, estrogens, androgens and glucocorticoids are involved in pregnancy from implantation to parturition. Their biosynthesis and their metabolism result from complex pathways involving the fetus, the placenta and the mother. The absence of expression of some steroïdogenic enzymes as CYP17 in placenta and in adrenal fetal zone and the better determination of the onset and variation of others especially HSD3B2 during the pregnancy explain the production of the steroid hormones. Moreover the consequences of some disorders of steroidogenesis (especially aromatase, POR, CYP11A1 and 21-hydroxylase deficiencies) in fetus and mother during the pregnancy have permit to elucidate these complex pathways. This better knowledge of steroid hormones production associated with their dosages in maternal plasma/urine or amniotic fluid using new specific assays as LC-MS MS could facilitate the follow-up of normal and pathological pregnancies. Moreover, these advances should be a basis to evaluate the impact of multiple pathologies of the pregnancy and pharmacologic and xenobiotic consequences on their metabolism.     

Pitfalls of prenatal diagnosis of 21-hydroxylase deficiency congenital adrenal hyperplasia

Hormonal measurements and HLA genotyping of amniotic fluid at midgestation correctly predicted the postnatal diagnosis of congenital adrenal hyperplasia (CAH) in 29 of 32 fetuses at risk. Of these 29, 7 were predicted to have prenatal-onset classical 21-hydroxylase deficiency (21-OH def) based on elevated amniotic fluid 17-hydroxyprogesterone (17-OHP) and delta 4-androstenedione (delta 4-A) levels. These 7 fetuses and their index cases were ultimately proven to have salt-wasting classical 21-OH def. Of 5 who were HLA typed, the genotype was identical to the index case in 4; in one, HLA prediction was not possible, because the parents shared identical HLA antigens. Normal amniotic fluid 17-OHP and delta 4-A levels in the remaining 22 fetuses predicted that they were not affected with classical CAH. These children have been clinically asymptomatic to date or proven biochemically not to have classical or nonclassical CAH. Of the 22 fetuses, 11 were predicted by HLA genotyping to be homozygous normal or heterozygous for 21-OH def. In 3 of the 32 fetuses, prenatal diagnosis was incorrect. In one, the fetus was predicted to have CAH based on HLA identity to the index case. However, amniotic fluid 17-OHP and delta 4-A were normal, and the fetus was normal. The index case of this family did not have CAH, but was a normal child. Thus, amniotic fluid hormone levels accurately predicted a normal fetus, while HLA genotyping was not relevant in prenatal diagnosis because the index case was unaffected. The second fetus was predicted to be affected on the basis of HLA genotyping and to be unaffected based on normal amniotic fluid 17-OHP and delta 4-A. During infancy, this female infant had postnatal-onset nonclassical CAH. The index case in this family, presumed to have classical simple virilizing CAH, was later diagnosed to have nonclassical CAH. Thus, in nonclassical CAH, hormonal measurement of 17-OHP and delta 4-A is not useful in prenatal diagnosis; only HLA genotyping of the fetus is valuable. In the third case, the fetus was predicted to be a heterozygote by HLA genotyping and to be unaffected by hormonal measurement. Postnatally, at age 2 7/12 yr, the male child was found to have classical simple virilizing CAH and to be HLA-B-DR identical to his brother (index case) who also has classical simple virilizing CAH.(ABSTRACT TRUNCATED AT 400 WORDS)