Amniotic Fluid Testosterone Research Articles

Elevated level of testosterone in amniotic fluid during prenatal stress and its association with development of Attention-Deficit/Hyperactivity Disorder (ADHD) like symptoms in toddlers.

To investigate the "prenatal testosterone hypothesis", according to which, high level of testosterone associated with the development of ADHD like symptoms in younger children, and to investigate whether maternal stress during pregnancy in-creases the risk of developing ADHD like symptoms in early childhood. This was a prospective study with three measurement periods: the first one during pregnancy (12 to 25 weeks of gestation); the second period involved the assessment of infants of this pregnancy at the age of 6 months and the third one the assessment of the same infants at the age of 18 months. The research plan is approved by "David Tvildiani Medical University" Research Ethics Committee. The study does not contain serious predictable risks as the expected benefit overweighs them. The study group is presented by 40 pregnant women and 40 infants of these pregnancies. Pregnant women were asked about their perceived stress levels, critical life events of the past year and pregnancy-specific stress levels using standardized questionnaires. Child's temperament and behavioral regulation were assessed using the questionnaires. Amniotic fluid was collected undergoing amniocentesis. Total testosterone in amniotic fluid was measured by radioimmunoassay. Although statistically significant relationship was identified between hyperactivity, also impulsiveness symptoms and pre-natal stress, no statistically significant relationship was identified between testosterone level and hyperactivity, also impulsivity symptoms, as well as between testosterone level and prenatal stress level. The performed study did not support the "hypothesis about prenatal testosterone", because there was a significant negative correlation between the frequency of hyperactivity symptoms and testosterone level.

Developmental vitamin D deficiency increases foetal exposure to testosterone

BackgroundAutism spectrum disorder (ASD) is a group of neurodevelopmental disorders which are more common in males. The ‘prenatal sex steroid’ hypothesis links excessive sex-steroid exposure during foetal life with the behavioural differences observed in ASD. However, the reason why sex steroid exposure may be excessive remains unclear. Epidemiological studies have identified several environmental risk factors associated with ASD, including developmental vitamin D (DVD) deficiency. We have demonstrated in an animal model that DVD-deficiency is associated with a hyper-inflammatory response in placentas from male but not female foetuses. Vitamin D also regulates the expression of several steroidogenic enzymes in vitro. Therefore using this animal model, we have examined whether DVD-deficiency leads to increased sex-steroid levels in both the maternal and foetal compartments.MethodsFemale rats are fed a vitamin D deficient diet from 6 weeks before mating until tissue collection at embryonic day 18. We examined the levels of testosterone, androstenedione and corticosterone in maternal plasma, foetal brains and amniotic fluid. We further examined gene expressions of steroidogenic enzymes and DNA methylation of aromatase promoters in foetal brains as a potential molecular mechanism regulating testosterone expression.ResultsWe show that DVD-deficiency increases testosterone levels in maternal blood. We also show elevated levels of testosterone and androstenedione in the amniotic fluid of female but not male DVD-deficient foetuses. Testosterone levels were also elevated in DVD-deficient male brains. Vitamin D, like other steroid-related hormones, regulates gene expression via methylation. Therefore we examined whether the significant elevation in testosterone in male brains was due to such a potential gene-silencing mechanism. We show that the promoter of aromatase was hyper-methylated compared to male controls.LimitationsA reduction in aromatase, in addition to causing excessive testosterone, could also lead to a reduction in estradiol which was not examined here.ConclusionsThis study is the first to show how an epidemiologically established environmental risk factor for ASD may selectively elevate testosterone in male embryonic brains. These findings provide further mechanistic support for the prenatal sex steroid theory of ASD.

Prenatal androgen exposure and children's gender-typed behavior and toy and playmate preferences

We report findings from two studies investigating possible relations of prenatal androgen exposure to a broad measure of children's gender-typed behavior, as well as specifically to children's toy and playmate preferences. Study 1 investigated these outcomes for 43 girls and 38 boys, aged 4 to 11 years, with congenital adrenal hyperplasia (CAH, a genetic condition causing increased adrenal androgen production beginning prenatally) compared to similarly-aged, unaffected relatives (41 girls, 31 boys). The predicted sex differences were found for all of the outcome measures. Furthermore, girls with CAH showed increased male-typical and decreased female-typical behavior and toy and playmate preferences compared to unaffected girls. Study 2 investigated the relationship of amniotic fluid testosterone to gender-typed behavior and toy and playmate preferences in typically developing children (48 girls, 44 boys) aged 3 to 5 years. Although the predicted sex differences were found for all of the outcome measures, amniotic fluid testosterone was not a significant correlate, in the predicted direction, of any outcome measure for either sex. The results of study 1 provide additional support for an influence of prenatal androgen exposure on children's gender-typed behavior, including toy and playmate preferences. The results of study 2 do not, but amniotic fluid testosterone may be an insufficiently sensitive measure of early androgen exposure. A more sensitive and reliable measure of prenatal androgen exposure may be needed to consistently detect relations to later gender typed behavior in non-clinical populations.

Prenatal androgen exposure and children's aggressive behavior and activity level

Some human behaviors, including aggression and activity level, differ on average for males and females. Here we report findings from two studies investigating possible relations between prenatal androgen and children's aggression and activity level. For study 1, aggression and activity level scores for 43 girls and 38 boys, aged 4 to 11years, with congenital adrenal hyperplasia (CAH, a genetic condition causing increased adrenal androgen production beginning prenatally) were compared to those of similarly-aged, unaffected relatives (41 girls, 31 boys). Girls with CAH scored higher on aggression than unaffected girls, d=0.69, and unaffected boys scored higher on activity level than unaffected girls, d=0.50. No other group differences were significant. For study 2, the relationship of amniotic fluid testosterone to aggression and activity level was investigated in typically-developing children (48 girls, 44 boys), aged 3 to 5years. Boys scored higher than girls on aggression, d=0.41, and activity level, d=0.50. However, amniotic fluid testosterone was not a significant predictor of aggression or activity level for either sex. The results of the two studies provide some support for an influence of prenatal androgen exposure on children's aggressive behavior, but not activity level. The within-sex variation in amniotic fluid testosterone may not be sufficient to allow reliable assessment of relations to aggression or activity level.

Maternal and female fetal testosterone levels are associated with maternal age and gestational weight gain.

ObjectivePrenatal androgen exposure has been suggested to play a role in polycystic ovary syndrome. Given the limited information on what maternal characteristics influence maternal testosterone levels, and the even less explored routes by which female fetus androgen exposure would occur, the aim of this study was to investigate the impact of maternal age, BMI, weight gain, depressed mood and aromatase SNPs on testosterone levels in maternal serum and amniotic fluid of female fetuses.MethodsBlood samples from pregnant women (n = 216) obtained in gestational weeks 35–39, and pre-labor amniotic fluid samples from female fetuses (n = 56), taken at planned Caesarean section or in conjunction with amniotomy for induction of labor, were analyzed. Maternal serum testosterone and amniotic fluid testosterone and cortisol were measured by tandem mass spectrometry.ResultsMultiparity (β = −0.28, P < 0.001), self-rated depression (β = 0.26, P < 0.001) and weight gain (β = 0.18, P < 0.05) were independent explanatory factors for the maternal total testosterone levels. Maternal age (β = −0.34, P < 0.001), weight gain (β = 0.19, P < 0.05) and amniotic fluid cortisol levels (β = 0.44, P < 0.001) were independent explanatory factors of amniotic fluid testosterone in female fetuses, explaining 64.3% of the variability in amniotic fluid testosterone.Wider implications of the findingsYoung maternal age and excessive maternal weight gain may increase the prenatal androgen exposure of female fetuses. Further studies are needed to explore this finding.

Measurement of amniotic fluid steroids of midgestation via LC–MS/MS

IntroductionAnalysis of steroids by mass spectrometry (MS) has evolved into a reliable tool for the simultaneous detection of multiple steroids. As amniotic fluid (AF) and fetal serum composition of early pregnancy are closely related, the analysis of AF can yield information on the physiological status of the developing fetus. We evaluated the use of liquid-chromatography tandem mass spectrometry (LC–MS/MS) for AF steroid analysis, including the analysis of its sensitivity and accuracy for gender verification in healthy subjects. Materials and methodsAF of 78 male and 94 female healthy newborns was analyzed by LC–MS/MS at 16 weeks of gestation. The levels of androstenedione, corticosterone, cortisol, cortisone, deoxycorticosterone, 11-deoxycortisol, dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA-S), 17-hydroxyprogesterone, progesterone (17-OHP) and testosterone were measured. Steroid levels were compared to RIA and GC–MS levels of midgestation from the literature. Cross-validated logistic regression was used to obtain statistical predictions of gender at birth from testosterone and the above steroids. ResultsLC–MS/MS analysis of AF steroids yielded comparable results with published GC–MS data. Gender specific differences were found for androstenedione and testosterone concentrations with higher levels in the male fetus. In contrast to published RIA data no gender specific differences were observed for 17-hydroxyprogesterone and dehydroepiandrosterone AF concentrations. Testosterone concentrations yielded highly accurate predictions for male gender at birth. Additional analysis of further steroids did neither increase the accuracy, sensitivity nor specificity of this prediction. The estimated optimal cut-off value for amniotic testosterone level was 0.074μg/L for healthy male newborns. ConclusionsLC–MS/MS is a reliable method for the determination of steroids in amniotic fluid. The determination of testosterone in amniotic fluid by LC–MS/MS in early pregnancy of healthy subjects can be used to offer a reliable prediction of fetal gender at birth.

Digit ratio (2D:4D) in newborns: Influences of prenatal testosterone and maternal environment

IntroductionThe 2D:4D digit ratio is sexually-dimorphic, probably due to testosterone action through the perinatal period. We characterize the 2D:4D ratio in newborn (NB) infants, in between the pre- and postnatal surges of testosterone, and relate it to the mother's 2D:4D and to testosterone levels in the amniotic fluid (AF). Subjects and methodsTestosterone was assayed in samples of maternal plasma and AF collected at amniocentesis. Shortly after birth, 106 NBs and their mothers were measured for 2D:4D ratio. ResultsNB males had lower mean 2D:4D ratios than females but this dimorphism was significant only for the left hand (males: 0.927; females: 0.950; p=0.004). Mothers who had sons had lower 2D:4D ratios than those who had daughters and the mother's 2D:4D were higher than those of NBs regardless of sex. Both hands of NB females were negatively correlated with AF testosterone and positively correlated with the mother's 2D:4D, but males showed no significant associations. Maternal plasma testosterone also showed a negative weak correlation with NB's digit ratio in both sexes. ConclusionsSexual dimorphism at birth was only significant for the left hand, in contrast with reports of greater right hand dimorphism, suggesting that postnatal testosterone is determinant for 2D:4D stabilization. The lower 2D:4D ratios in mothers who had sons support claims that hormone levels in parents are influential for determining their children's sex. NB female's digit ratio, but not males', was associated to the level of AF testosterone. The mother's 2D:4D ratios were positively correlated with their daughters' 2D:4D, but the same was not observed for male NBs, suggesting that prenatal testosterone levels in male fetus lead their 2D:4D ratios to stray from their mothers' with high individual variability.

Maternal Antenatal Anxiety and Amniotic Fluid Cortisol and Testosterone: Possible Implications for Foetal Programming

Both animal and human studies have shown that maternal stress or anxiety during pregnancy is associated with increased risk of disturbance in offspring neurodevelopment and behaviour. In animal models, increased foetal exposure to glucocorticoids has been found to be one mechanism for such foetal programming. Little is understood of the mediating mechanisms in humans, and one aim of our research programme is to investigate this further. This review presents a synopsis of some of our recent results. We aimed to test the hypothesis that maternal anxiety was associated with raised maternal cortisol, and that this in turn was related to increased foetal exposure to cortisol. We studied this by recruiting women at amniocentesis, obtained their Spielberger State Anxiety scores, and assessed maternal plasma cortisol and amniotic fluid cortisol. We also examined maternal plasma and amniotic fluid testosterone levels. Awaiting amniocentesis was in general anxiogenic, but with a wide range of anxiety scores. Maternal anxiety was significantly associated with plasma cortisol before 17 weeks, albeit of modest magnitude (r = 0.0.23), and not after 17 weeks of gestation. This is probably due to the known attenuation of the maternal hypothalamic-pituitary-adrenal axis with increasing gestation. We found a strong correlation between maternal plasma and amniotic fluid cortisol levels, which increased with gestation and became robust after 18 weeks. This correlation increased with maternal anxiety, suggesting a possible effect of maternal mood on placental function. There was a positive correlation between cortisol and testosterone in amniotic fluid, in both male and female foetuses independent of maternal anxiety, plasma testosterone, gestational age, and time of collection. Foetal stress may be associated with increased foetal exposure to testosterone. However, maternal anxiety did not predict amniotic fluid cortisol or testosterone level. Thus, the role of these hormones in mediating the effect of maternal mood on foetal development in humans remains to be demonstrated.

Amniotic fluid testosterone: relationship with cortisol and gestational age

Foetal exposure to testosterone is increasingly implicated in the programming of future reproductive and non-reproductive behaviour. Some outcomes associated with prenatal exposure to testosterone may be predicted from exposure to prenatal stress, suggesting a link between them. The peak serum levels of testosterone in the foetus are thought to be around 14-18 weeks' gestation, and we explored testosterone levels at different gestations. Although best investigated in foetal plasma, this is now difficult because of the decline in frequency of foetal blood sampling; in this study, we used amniotic fluid as a biomarker to investigate foetal exposure. To investigate the relationship between amniotic fluid testosterone, amniotic fluid cortisol, foetal gender, and gestational age. Paired amniotic fluid and maternal plasma samples were collected from 264 pregnant women undergoing amniocentesis between 15 and 37 weeks' gestation (median 17 weeks [119 days]). Total testosterone and cortisol in amniotic fluid, and total plasma testosterone (maternal) were measured by radioimmunoassay. Amniotic fluid testosterone levels were higher in male than in female foetuses, with a median (interquartile range) of 0.85 nmol/l (0.60-1.17 nmol/l) and 0.28 nmol/l (0.175-0.45 nmol/l), respectively. No relationship between amniotic fluid testosterone and gestational age was detected in either sex. Amniotic fluid testosterone correlated positively with amniotic fluid cortisol in both sexes (r = 0.30 male foetuses, r = 0.33 female foetuses, P < 0.001 for both), and remained significant in multivariate analysis. Testosterone in amniotic fluid did not change with gestation in the second and third trimester, raising questions about the timing of the reported early peak in the male foetus. The positive correlation between cortisol and testosterone in amniotic fluid suggests that increased foetal exposure to cortisol may also be associated with increased exposure to testosterone.

PRENATAL DIAGNOSIS OF CONGENITAL ADRENAL HYPERPLASIA DUE TO 21-HYDROXYLASE DEFICIENCY

Prenatal diagnosis of the classic forms of the congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency has progressed at the same time as the advances made in the field of both endocrinology and molecular genetics. In 1975, prenatal diagnosis of CAH was first made in the second trimester on the basis of raised levels of 17-hydroxyprogesterone (17-OHP) in the amniotic fluid (AF). Later an indirect prenatal diagnosis based on the genetic tracking of CAH was greatly facilitated by its linkage to HLA. By 1979, to obviate the need for corrective genital surgery the virilized genitalia in CAH female fetuses, a prenatal treatment was proposed by giving dexametfiasone to the mother in early pregnancy, and later was shown to be successful. Rapidly, there was a demand for an early prenatal diagnosis of the affection. This was rendered possible by the advances in molecular biology associated with the practice of chorionic villus biopsy. Prenatal diagnosis was then done in the first trimester of the pregnancy, by either HLA typing using HLA-DNA probes or direct studies of the genetic abnormalities of the C4-CYP21 locus. In practice, four methods have been, and can still be used : measurement of AF levels of 17-OHP, HLA typing, molecular studies of the C4-CYP21 genes, all in association with fetal sex determination (measurement of AF testosterone levels, karyotype and more recently detection of Y-chromosome specific sequences). Steroid analysis remains a simple and safe method in the absence of prenatal treatment and the only informative method when there is no previous family study. Nowadays, an early and accurate prenatal diagnosis can be achieved by molecular genetic studies on DNA extracted from chorion villus samples, but it requires the previous study of the nuclear family. The choice between HLA typing and direct C4-CYP21 loci studies depend on the possibilities and expertise of a given laboratory. HLA typing is still more often used with the improvement of using molecular studies instead of serological methods because almost all families are then informative. Nevertheless, HLA typing is unreliable in some circumstances: in case of a recombination event (1 % in our studies of over 250 families) or de novo mutation(s) and when the index case is deceased or not available. Studies of the C4-CYP21 gene locus by Southern blotting and the CYP21B gene mutations by PCR method have not these disadvantages. In our hands, Southern blotting study of the duplicated C4-CYP21 region has shown some complex genetic rearrangements and is fully informative method for prenatal diagnosis in about 60% of CAH families. The 9 most common point mutations of the CYP21B gene causing CAH (and also present in the CYP21A pseudogene) can be detected after specific PCR amplification of the functional CYP21B gene. In these conditions, almost all families are informative in our experience. Moreover, using this direct genetic analysis associated with the possibility to detect the heterozygotes in a non related-CAH population, a prenatal diagnosis could be done in a family without a previous CAH affected child. A prenatal diagnosis in the first trimester is required in order to stop unnecessary prenatal treatments (if unaffected female fetuses and all males fetuses), or when the parents wish to interrupt the pregnancy in case of a CAH affected fetus. In our experience using molecular genetics of the CYP21-C4 loci and sex determination by PCR method (SRY, Y-chromosome repeated sequences) or karyotype, prenatal diagnosis has been successfully done in 23 pregnancies at risk 1:4. In one case, there was no previous family study because the index c;>se was dead; in an other family, the only informations were the state of heterozygoty of the parents: one being a relative of a characterized CAH family, the other being detected by a systematic ACTH test and confirmed by mutation studies.

Amniotic fluid testosterone and testosterone glucuronide levels in the determination of foetal sex

Unconjugated testosterone levels were assayed in 351 amniotic fluid samples obtained at 15–19 weeks gestation. The median values for unconjugated testosterone in the 166 female foetuses and 185 male foetuses were 137 and 712pmol/1 respectively. Sixteen amniotic fluid samples from male foetuses had unconjugated testosterone levels lower than the highest female unconjugated testosterone value (361 pmol/1). Testosterone glucuronide was measured in amniotic fluid from 48 female and 55 male foetuses. There was a significant sex difference in the median values of testosterone glucuronide between female (median 160 pmol/1, range 64–465 pmol/1) and male (median 817 pmol/1, range 68–3707 pmol/1) amniotic fluid specimens ( P < 0.001). Of the sixteen male foetuses with amniotic fluid unconjugated testosterone levels in the female range, 12 had amniotic fluid testosterone glucuronide levels within the male testosterone glucuronide range of values. Hence used in conjunction with uneonjugated testosterone, testosterone glucuronide increased the predictive accuracy of foetal sexing from 95.4 to 98.9%. Testosterone sulphate was measured in 24 female and 25 male amniotic fluid samples. There was no significant difference between female (median 2591 pmol/1) and male (median 2964 pmol/1) testosterone sulphate levels.

Elevated concentrations of the β-subunit of human chorionic gonadotropin and testosterone in the amniotic fluid of gestations of diabetic mothers

Hyperplasia of testicular Leydig cells and ovarian theca-lutein cells is a common histologic finding in infants of diabetic mothers. The functional correlates of this histologic finding were investigated by measurement of the R-subunit of human chorionic gonadotropin, testosterone, dihydrotestosterone, androstenedione, estradiol, and estrone in the amniotic fluid compartment of gestations with male and female fetuses in diabetic mothers (N = 34) and control women (N = 34) at term. When compared with those of control subjects, gestations of diabetic mothers had significantly higher amniotic fluid concentrations of the R-subunit of human chorionic gonadotropin. Gestations with either male or female fetuses in diabetic mothers had significantly higher amniotic fluid testosterone and dihydrotestosterone levels when compared with those of their respective gender controls. In gestations with male fetuses in diabetic mothers there was a significant positive correlation between the β-subunit of human chorionic gonadotropin and testosterone. There was no significant difference in amniotic fluid androstenedione, estradiol, or estrone levels between the gestations of diabetic mothers and those of control women. These results suggest that the testicular Leydig cell and ovarian theca-lutein cell hyperplasia seen in infants of diabetic mothers is due, in part, to elevated levels of human chorionic gonadotropin and is associated with elevated testosterone and dihydrotestosterone concentrations in the amniotic fluid.

Testosterone levels in midtrimester maternal and fetal plasma and amniotic fluid.

Testosterone was measured in maternal plasma (58 samples), amniotic fluid (71 samples) and fetal plasma (55 samples) in 79 patients between 15 and 23 weeks' gestation. Maternal plasma testosterone levels were unrelated to fetal sex. Amniotic fluid testosterone was significantly higher in male than female fetuses but did not reliably predict fetal sex. A correct diagnosis of fetal sex was made by testosterone assay of pure fetal plasma in 39 out of 40 males and in 15 out of 15 females using 1.70 nmol/l as the cut-off value. This investigation is not the method of choice for routine fetal sexing but may be of value in fetuses suspected of having certain endocrine disorders.

Prenatal sex diagnosis: testosterone and FSH levels in mid-trimester amniotic fluids.

We studied the validity of mid-trimester amniotic fluid testosterone and FSH in the diagnosis of fetal sex in abnormal fetuses and in twins. It was found that the testosterone/FSH ratio, but not the level of the individual hormones, was an excellent criterion for fetal sex diagnosis. In a control group of 32 female and 34 male fetuses, the testosterone/FSH ratio was diagnostic. In two cases the values were indeterminate and fetal sex could not be predicted, but there were no false diagnoses. The abnormalities of the fetuses were diagnosed by karyotype analyses or raised levels of alpha-fetoprotein. It was found that neither autosomal trisomies nor X-chromosome aneuploidy or neural tube defect interfered with the diagnostic value of the hormonal approach. The twin study included 14 pairs, three of whom were discordant for sex. In all twins the fetal sex diagnosis was appropriate. In co-twins of the same sex the hormone levels were very close to each other.

Measurement of sex hormone binding globulin in human amniotic fluid: its relationship to protein and testosterone concentrations, and fetal sex.

Sex hormone binding globulin (SHBG) has been identified and quantified in human amniotic fluid. Identification was based on its electrophoretic mobility on polyacrylamide gels and its steroid binding characteristics, which were identical to those attributed to SHBG in pregnancy serum. Amniotic fluid SHBG binding capacity was measured by competitive saturation analysis using [3H]-5 alpha-dihydrotestosterone as the labelled ligand, after removal of endogenous steroids with dextran-coated charcoal. Similar amniotic fluid SHBG binding capacities were found in samples taken during early (13-20 weeks, 8.5 +/- 5.1 (SD) nmol/l, n = 10) and late (36-37 weeks, 8.7 +/- 3.0 nmol/l, n = 28) pregnancy. In comparison with pregnancy serum SHBG levels (390 +/- 140 nmol/l, n = 5), amniotic fluid SHBG was not enriched in relation to the relative concentrations of total proteins, albumin or transferrin. Amniotic fluid is therefore not a better source for the purification of SHBG than pregnancy serum. There were no differences in amniotic fluid SHBG levels with respect to fetal sex, but positive correlations were observed between SHBG binding capacities and testosterone concentrations in amniotic fluid from both male (r = 0.68, P less than 0.001) and female (r = 0.53, P less than 0.05) fetuses. It is suggested that SHBG may sequester free testosterone in amniotic fluid, and that measurements of SHBG in amniotic fluid may help to more accurately identify fetal sex in cases where borderline amniotic fluid testosterone concentrations are found.

Testosterone and dihydrotestosterone in amniotic fluid and foeto-placental membranes from the guinea pig

Testosterone (T) and dihydrotestosterone (DHT) in the amniotic fluid (AF) and foeto-placental membranes (FPM) (yolk-sac + amnion) from 180 male and female guinea-pig foetuses were determined by radioimmunoassay on days 28, 32, 36, 40, 44, 48, 52, 56, 60, 64 of gestation. In male foetus the evolution of androgens in the fluid is characterized by two sharp rises, the former at the time of sexual differentiation on day 32 (T = 219.1 +/- 39.1 and DHT = 74.7 +/- 10.0 fmol/ml) the latter, which affects only DHT, on day 52 (DHT = 68.5 +/- 10.3 fmol/ml). In female foetus, AF T concentrations (mean = 36.3 fmol/ml) are comparable to the lowest T concentrations observed in male, while DHT concentrations (less than 2.5 fmol/ml), are significantly lower than those observed in the male (mean = 28.9 fmol/ml) and without any overlap in the values. Thus, in guinea pig, DHT, but not testosterone allows to predict accurately the foetal sex at any stage studied. Testosterone and DHT are also present in FPM and their concentrations were comparable for male and female foetuses in most stages, values varying between 400 and 1600 fmol/g of tissue with a light predominance of DHT compared with T; in both sexes, general evolution of androgens is marked by a rapid drop between days 28 and 44 followed by a significant increase between days 44 and 64. Possible origins of androgens in AF and FMP are discussed.

The concentration of progesterone, 20 alpha-dihydroprogesterone, testosterone, oestrone and oestradiol-17 beta in serum, amniotic fluid and placental tissue of pregnant rabbits.

The concentrations of progesterone (delta 4P), 20 alpha-dihydroprogesterone (20 alpha-DHP), testosterone (T), oestrone (E1) and oestradiol-17 beta (E2 beta) in peripheral blood serum (PBS), amniotic fluid (AF) and placental tissue of rabbits during gestation were determined by radioimmunoassay. The placenta of the 10-day pregnant rabbit was fragile and composed mainly of maternal tissue. By the 12th day of pregnancy it was separable into maternal and foetal placentae. The mean concentration of delta 4P in PBS rose from 200 pg/ml (day 1 pregnancy) to 17--21 ng/ml (days 10--15) and decreased gradually to 1 ng/ml a few hours before parturition. The 20 alpha-DHP in PBS also showed an increase from 1.5 ng/mg (day 1) to 12 ng/ml (day 6) but fluctuated thereafter. The concentration of 20 alpha-DHP in the PBS tended to be lower than that of delta 4 P during pregnancy until the regression of the corpus luteum. An interesting observation was an increase of T on days 6--8 of pregnancy, the time when implantation occurs. The concentrations of E1 and E2 beta in PBS remained very low throughout pregnancy. delta 4P and 20 alpha-DHP in AF ranged between 25 pg to 1 ng/ml and in no case during the course of pregnancy were the levels of T, E1 and E2 beta in AF higher than in PBS. Where the maternal placental delta 4P content remained between 1--2 ng/placenta, the foetal placenta delta 4P rose to a level of 15 ng/placenta by day 31 of pregnancy. A similar trend was recorded for 20 alpha-DHP content. It is concluded that although a parallelism between PBS and myometrial steroid concentration was observed, no relationship could be drawn between the concentrations of steroid in PBS and those of the placental tissue and AF.

Amniotic fluid testosterone and follicle-stimulating hormone for fetal sex determination in the second trimester of pregnancy

SummaryThe concentrations of testosterone and follic estimulating hormone (FSH) in amniotic fluid were determined in 110 pregnancies, from 11 to 22 weeks maturity. Fifty-eight of the fetuses were male and 52 were female. The two indices were compared for their value for fetal sex diagnosis in the second trimester.Mean testosterone concentration was 3·5 times higher in the presence of a male fetus. After 13 weeks, fetal sex could be predicted in 38 of the 43 subjects with a male fetus and in 34 of the 38 subjects with a female fetus. After 13 weeks, mean FSH concentration was 4·6 times higher with a female than a male fetus. Fetal sex could be predicted with FSH in 19 of the 38 subjects with a female fetus. Determination of testosterone is a valuable index and should be carried cut in the first instance. FSH should be determined in cases where the testosterone level is equivocal. This permitted diagnosis in every instance

Amniotic fluid testosterone and fetal sex determination (discussion of the endocrine function of the fetal testis).

Amniotic fluid testosterone levels were determined by the radioimmunoassay technique in 101 samples obtained by amniocentesis between 16 and 18 weeks of gestation from women with increased risk of chromosomal abnormalities. Fetal sex was determined by cell culture and chromosomal analysis of fetal amniotic cells and was confirmed at birth. In pregnancies with male fetuses (50 samples), the mean amniotic fluid testosterone level of 216 pg/ml (+/- 75) was significantly higher (p less than 0.001) than the mean value of 93 pg/ml (+/- 28) found in pregnancies with female fetuses (51 samples). The range for pregnancies with male fetuses was 130 to 500 pg/ml and for those with female fetuses 10 to 140 pg/ml, showing an area of overlap from 130 to 140 pg/ml.

Peripheral Concentrations of Gonadotropins and Progestins During Pregnancy in Rabbits After Active Immunization Against Testosterone

The effects of active immunization of female rabbits against testosterone on various endocrine parameters during pregnancy were examined. Peripheral blood samples were obtained from immunized rabbits at timed intervals after mating up to the 29th day of pregnancy, when the rabbits were killed and various tissues were analyzed. Progesterone concentrations were higher in testosterone-immunized rabbits (TIR) than in controls during pregnancy. Luteinizing hormone (LH) and follicle-stimulating hormone concentrations were not significantly different in controls and TIR during pregnancy. Both progestins and gonadotropins showed the expected coitus-induced increases, but LH levels were higher in TIR. The binding of testosterone in fetal plasma and amniotic fluid was higher in TIR than in controls. Weights of fetuses and litter size were not significantly different in TIR and controls. These data suggest that testosterone may play a role during pregnancy in the rabbit.