Second-trimester Amniotic Fluid Research Articles

Metabolomic Profiling of Second-Trimester Amniotic Fluid for Predicting Preterm Delivery: Insights from NMR Analysis.

Preterm delivery (PTD) is a notable pregnancy complication, affecting one out of every ten births. This study set out to investigate whether analyzing the metabolic composition of amniotic fluid (AF) collected from pregnant women during the second trimester of pregnancy could offer valuable insights into prematurity. The research employed 1H-NMR metabolomics to examine AF samples obtained from 17 women who gave birth prematurely (between 29+0 and 36+5 weeks of gestation) and 43 women who delivered at full term. The application of multivariate analysis revealed metabolites (dimethylglycine, glucose, myo-inositol, and succinate) that can serve as possible biomarkers for the prognosis and early diagnosis of preterm delivery. Additionally, pathway analysis unveiled the most critical metabolic pathways relevant to our research hypothesis. In summary, these findings suggest that the metabolic composition of AF in the second trimester can be a potential indicator for identifying biomarkers associated with the risk of PTD.

Amniotic fluid rubidium concentration association with newborn birthweight: a maternal-neonatal pilot study

Although most biological systems, including human tissues, contain rubidium, its biogeochemical functions and possible role in neonatal birthweight are largely unknown. An animal study indicated a correlation between rubidium deficiency in the maternal diet and lower newborn birthweight. This pilot study measured rubidium concentrations in amniotic fluid during the second trimester of (low-risk) pregnancy and investigated potential correlations between rubidium levels and third-trimester newborn birthweight-small for gestational age, appropriate for gestational age, and large for gestational age-and between preterm birth and term birth in uncomplicated pregnancies. This prospective, single-center study investigated a possible relationship between rubidium concentration in second-trimester amniotic fluid and third-trimester birthweight percentile. Amniotic fluid (at a median gestational age of 19 weeks) was sampled to determine rubidium concentration. Maternal and newborn characteristics were obtained from participant and delivery records. After screening 173 pregnant women, 99 amniotic fluid samples were evaluated. Midpregnancy median rubidium concentrations were significantly lower among newborns that were classified as small for gestational age than among newborns that were classified as appropriate for gestational age (106 vs 136 μg/L; P<.01). Based on a logistic regression random forest model, amniotic fluid rubidium was identified as a significant contributing factor to appropriate-for-gestational-age birthweight with 54% of the total contribution. Amniotic fluid rubidium concentration seems to be a strong predictor of appropriate-for-gestational-age birthweight and a potential marker for newborn birthweight classifications. In particular, low rubidium concentrations in amniotic fluid during midpregnancy are linked to third-trimester lower birthweight percentile. These findings could potentially serve as a valuable tool for early identification of pregnancy outcomes. Further investigation is necessary to fully explore the effect of rubidium on fetal development.

The relationship between second-trimester amniotic fluid CRP levels and pregnancy outcomes

The relationship between second-trimester amniotic fluid CRP levels and pregnancy outcomes

Amniotic Fluid-Derived Mesenchymal Stem/Stromal Cell-Derived Secretome and Exosomes Improve Inflammation in Human Intestinal Subepithelial Myofibroblasts.

Inflammatory Bowel Diseases (IBDs) are characterized by chronic relapsing inflammation of the gastrointestinal tract. The mesenchymal stem/stromal cell-derived secretome and secreted extracellular vesicles may offer novel therapeutic opportunities in patients with IBD. Thus, exosomes may be utilized as a novel cell-free approach for IBD therapy. The aim of our study was to examine the possible anti-inflammatory effects of secretome/exosomes on an IBD-relevant, in vitro model of LPS-induced inflammation in human intestinal SubEpithelial MyoFibroblasts (SEMFs). The tested CM (Conditioned Media)/exosomes derived from a specific population of second-trimester amniotic fluid mesenchymal stem/stromal cells, the spindle-shaped amniotic fluid MSCs (SS-AF-MSCs), and specifically, their secreted exosomes could be utilized as a novel cell-free approach for IBD therapy. Therefore, we studied the effect of SS-AF-MSCs CM and exosomes on LPS-induced inflammation in SEMF cells. SS-AF-MSCs CM and exosomes were collected, concentrated, and then delivered into the cell cultures. Administration of both secretome and exosomes derived from SS-AF-MSCs reduced the severity of LPS-induced inflammation. Specifically, IL-1β, IL-6, TNF-α, and TLR-4 mRNA expression was decreased, while the anti-inflammatory IL-10 was elevated. Our results were also verified at the protein level, as secretion of IL-1β was significantly reduced. Overall, our results highlight a cell-free and anti-inflammatory therapeutic agent for potential use in IBD therapy.

Identification of a novel gene signature in second-trimester amniotic fluid for the prediction of preterm birth

Preterm birth affects approximately 5% to 7% of live births worldwide and is the leading cause of neonatal morbidity and mortality. Amniotic fluid supernatant (AFS) contains abundant cell-free nucleic acids (cfNAs) that can provide genetic information associated with pregnancy complications. In the current study, cfNAs of AFS in the early second-trimester before the onset of symptoms of preterm birth were analyzed, and we compared gene expression levels between spontaneous preterm birth (n = 5) and term birth (n = 5) groups using sequencing analysis. Differential expression analyses detected 24 genes with increased and 6 genes with decreased expression in the preterm birth group compared to term birth. Upregulated expressions of RDH14, ZNF572, VOPP1, SERPINA12, and TCF15 were validated in an extended AFS sample by quantitative PCR (preterm birth group, n = 21; term birth group, n = 40). Five candidate genes displayed a significant increase in mRNA expression in immortalized trophoblast HTR-8/SVneo cell with H2O2 treatment. Moreover, the expression of five candidate genes was increased to more than twofold by pretreatment with lipopolysaccharide in HTR-8/SVneo cells. Changes in gene expression between preterm birth and term birth is strongly correlated with oxidative stress and infection during pregnancy. Specific expression patterns of genes could be used as potential markers for the early identification of women at risk of having a spontaneous preterm birth.

Relationship between second-trimester amniotic fluid and plasma levels of angiopoietin-2 and thrombomodulin with adverse pregnancy outcome

Our objective is to investigate maternal midtrimester plasma and amniotic fluid (AF) levels of angiopoietin-2 (Ang-2) and thrombomodulin (TM), which are involved in vascular remodelling and endothelium activation, in placental disorders including foetal growth restriction (FGR) and preeclampsia (PE). This prospective multiparametric pilot study was conducted at the Perinatology Division of Trakya University in a population undergoing genetic amniocentesis. Both AF and plasma aliquots were kept in –80 °C until ELISA assay. The pregnancies were followed up until the end of gestation in terms of obstetric results. Amniotic fluid and plasma aliquots from 127 pregnancies who underwent genetic amniocentesis between 16 and 24 weeks of gestation were analysed. During the final data evaluation, 39 were excluded with various reasons. Twelve subsequently developed FGR and 11 complicated with PE. The control group (n = 65) was consisted of women delivered >37th week with an uncomplicated outcome. The midtrimester maternal Ang-2 levels in both AF and plasma and also TM levels in plasma were found to be significantly increased in pregnancies who subsequently developed FGR or PE (p< .05). The midtrimester Ang-2, which rises in both plasma and AF and the midtrimester TM, which only significantly increase in plasma compartment in PE group, as compensatory mechanism may be the precursors of placental disorders including FGR and PE. Impact Statement What is already known on this subject? It is known that angiopoietin-2 (Ang-2) has important role in placental angiogenesis and vascular remodelling. TM which is a receptor for Ang-2 plays a protective role in pregnancy by preventing the uteroplacental circulation from thrombosis. What do the results of this study add? The present study demonstrates that both midtrimester maternal plasma Ang-2/TM and amniotic fluid (AF) Ang-2 levels were significantly higher in PE and FGR group than uncomplicated group. Midtrimester AF TM levels were not significantly higher in PE group than the control group. What the implications are of these findings for clinical practice and/or further research? In the clinical practice, high levels of midtrimester Ang-2 and TM in plasma may be used for the prediction of FGR and PE. Although amniocentesis is not practical in the clinical use, the levels of these two markers in both AF and plasma compartments may contribute to explain the pathophysiology of FGR and PE.

Digit ratio (2D:4D) and amniotic testosterone and estradiol: an attempted replication of Lutchmaya etal. (2004).

The ratio of length between the second (index) and fourth (ring) fingers (digit ratio or 2D:4D) is frequently employed as a retrospective marker of prenatal sex hormone exposure. Lutchmaya etal. (2004) reported that the ratio of testosterone (T) to estradiol (E) present in second-trimester amniotic fluid was negatively correlated with digit ratios for the right hand (but not the left hand) in a sample of 29 children at 2-year follow-up. This observation is frequently cited as evidence for the measure's validity but has not been replicated. We therefore present the findings of another study of amniotic T and E that did not find evidence for these effects at 4½-year follow-up. The confidence intervals were large, the direction of correlations observed was generally erratic, and the overall findings question the premise that second-trimester sex hormones affect the development of digit length ratios in humans.

Associations between second-trimester amniotic fluid levels of ADAMTS4, ADAMTS5, IL-6, and TNF-α and spontaneous preterm delivery in singleton pregnancies.

Background We investigated the roles of inflammatory cytokines and the A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family in the etiopathogenesis of spontaneous preterm delivery by comparing the ADAMTS4, ADAMTS5, interleukin (IL)-6, and tumor necrosis factor-α (TNF-α) levels in second-trimester amniotic fluid between pregnant women with preterm birth and term controls. Methods All pregnant women who underwent second-trimester amniocentesis for genetic analysis between January 1, 2016, and January 1, 2018, were enrolled in this study. From this cohort, 22 patients who subsequently experienced spontaneous preterm delivery before 34 weeks of pregnancy formed the study group, and 22 age- and body mass index (BMI)-matched patients without preterm birth constituted the control group. Results No significant differences were observed between the preterm birth and control groups in terms of age, BMI, obstetric history of preterm delivery, gestational age at amniocentesis, or indication for amniocentesis. The mean amniotic fluid levels of ADAMTS4 and ADAMTS5 were significantly increased in the preterm birth group compared to the control group (248.3±22.6 and 182.4±19.8 pg/mL, P=0.012; and 198.6±21.6 and 159.1±21.7 pg/mL, P=0.035, respectively). Significantly increased IL-6 and TNF-α levels were also detected in the amniotic fluid of women who experienced spontaneous preterm delivery, relative to controls (142.1±16.2 and 95.8±16.4 pg/mL, P<0.001; and 139.4±12.5 and 89.6±11.2 pg/mL, P<0.001, respectively). Conclusion The results of this study imply that increased mid-trimester amniotic fluid levels of ADAMTS4, ADAMTS5, IL-6, and TNF-α play an important role in the pathophysiology of spontaneous preterm delivery.

Relationship between second-trimester amniotic fluid levels of Prokineticin-1 and Matrix Metalloproteinase-2 with adverse pregnancy outcome

To investigate the levels of Prokineticin-1 (PROK1) and matrix metalloproteinase-2 (MMP-2) in second-trimester amniotic fluid (AF). AF samples were investigated in 81 patients. AF-PROK1 and AF-MMP-2 were not significantly associated with adverse pregnancy outcomes (preeclampsia, intrauterine growth retardation, spontaneous preterm birth, gestational diabetes, gestational hypertension). AF-PROK1 levels in patients with abnormal first-trimester screening were significantly higher than those who underwent amniocentesis due to abnormal second-trimester screening tests (p = .04). AF-PROK1 or AF-MMP-2 do not have a role in the prediction of adverse pregnancy outcomes.

The attempt of human amniotic fluid colony-derived stem cells for cell therapy in animal model of ventricle injury

Objective To investigate the potential of human amniotic fluid colony-derived stem cells (hAFCSCs) transplanted into lateral ventricle injury in rats for cell therapy. Methods The second-trimester amniotic fluid samples were collected through amniocentesis by ultrasound from gestational age of 16 to 22 weeks for routine prenatal diagnosis purposes and samples were only used when cytogenetic analysis revealed no major abnormalities. Using colony poculum, hAFCSCs were isolated from second-trimester amniotic fluid. The ventricle damage model is divided into normal control group, control group and experimental group, blank control group. The hAFCSCs were injected into the ventricle of the animal model. To analyse the growth (weight, brain weight, open ears, grow hair) and sensorimotor function (foot test, reflection, limb position) change in model at several points. All statistic analysis of the data was performed with SNK to compare the difference of these groups. The protein of Nestin was detected using West blotting in the brain tissue of mode. Results There were no significant differences in body weight and brain weight of rats in each group. There was no remarkable difference in open ears between the experimental group, the control group and the blank control group, but there were notable differences between the mentioned groups and the control group. There were differences in sensorimotor function between experimental control group, blank control group and the normal control group, the experimental group; the experimental group were close to that of the normal control group. It showed that the expression of nestin after 5 days cells injection with Western blotting. Conclusion The hAFCSCs could improve the growth, sensorimotor function of the ventricle damage model rat. Key words: Human amniotic fluid colony-derived stem cells; Lateral ventricle injury; Animal model; Cell therapy

Low-level maternal exposure to nicotine associates with significant metabolic perturbations in second-trimester amniotic fluid

Decades of public health research have documented that smoking in pregnancy poses significant health risks to both mother and child. More recent studies have shown that even passive maternal exposure to secondhand smoke associates with negative birth outcomes. However, the mechanisms linking exposure to outcomes have remained obscure. As a first step toward defining the metabolic consequence of low-level nicotine exposure on fetal development, we conducted an untargeted metabolomic analysis of 81 paired samples of maternal serum and amniotic fluid collected from karyotypically normal pregnancies in the second trimester. By comparing the m/z and retention times of our mass spectral features with confirmed standards, we identified cotinine, a nicotine derivative, and used the calculated cotinine concentrations to classify our maternal serum samples into exposure groups using previously defined cut-offs. We found that cotinine levels consistent with low-level maternal exposure to nicotine associated with distinct metabolic perturbations, particularly in amniotic fluid. In fact, the metabolic effects in amniotic fluid of ostensibly low-level exposed mothers showed greater overlap with perturbations previously observed in the sera of adult smokers than did the perturbations observed in the corresponding maternal sera. Dysregulated fetal pathways included aspartate and asparagine metabolism, pyrimidine metabolism, and metabolism of other amino acids. We also observed a strong negative association between level of maternal serum cotinine and acetylated polyamines in the amniotic fluid. Combined, these results confirm that low-level maternal nicotine exposure, indicated by a maternal serum cotinine level of 2–10ng/mL, is associated with striking metabolic consequences in the fetal compartment, and that the affected pathways overlap those perturbed in the sera of adult smokers.

Investigating the Role of Fetal Gene Expression in Preterm Birth

Second-trimester amniotic fluid supernatant (AFS) contains cell-free fetal RNA (cffRNA) transcripts that can provide information about fetal gene expression. In a retrospective case-control study, we measured second-trimester fetal gene expression using cffRNA extracted from AFS in women who had spontaneous preterm birth (sPTB) <34 weeks and in women who delivered >37 weeks. We extracted cffRNA from AFS of women with singletons who had second-trimester genetic amniocenteses. Twenty-one gravidas who had sPTB and 21 term controls were matched 1:1 for maternal age, fetal sex, race, gestational age (GA) at the time of amniocentesis, and medication exposure. Cell-free fetal RNA was extracted and hybridized to a customized 65-gene NanoString panel containing genes related to oxidative stress, inflammation, and hypothalamic-pituitary-adrenal (HPA) axis and included 15 housekeeping genes. Two models were run, 1 examining sPTB in relation to case/control status and 1 examining sPTB in relation to GA as a continuous variable. Among cases, the gene expression of nitric oxide synthase 1 (NOS1), D-aspartate oxidase (DDO), and Beta-2-microglobulin (B2M) was higher than controls (P value < .05; false discovery rate-corrected Q value of ≤0.10). Nitric oxide synthase 1 and DDO are genes associated with oxidative stress; B2M is a marker of the fetal inflammatory response. Fetal HPA gene expression is not associated with GA at delivery or sPTB in second-trimester AFS. Alterations of fetal gene expression related to inflammation and oxidative stress antedate clinical symptoms and may be useful for early identification of patients at risk of having an sPTB.

Amniotic Fluid and Maternal Serum Metabolic Signatures in the Second Trimester Associated with Preterm Delivery.

Preterm delivery (PTD) represents a major health problem that occurs in 1 in 10 births. The hypothesis of the present study was that the metabolic profile of different biological fluids, obtained from pregnant women during the second trimester of gestation, could allow useful correlations with pregnancy outcome. Holistic and targeted metabolomics approaches were applied for the complementary assessment of the metabolic content of prospectively collected amniotic fluid (AF) and paired maternal blood serum samples from 35 women who delivered preterm (between 29 weeks + 0 days and 36 weeks +5 days gestation) and 35 women delivered at term. The results revealed trends relating the metabolic content of the analyzed samples with preterm delivery. Untargeted and targeted profiling showed differentiations in certain key metabolites in the biological fluids of the two study groups. In AF, intermediate metabolites involved in energy metabolism (pyruvic acid, glutamic acid, and glutamine) were found to contribute to the classification of the two groups. In maternal serum, increased levels of lipids and alterations of key end-point metabolites were observed in cases of preterm delivery. Overall, the metabolic content of second-trimester AF and maternal blood serum shows potential for the identification of biomarkers related to fetal growth and preterm delivery.

The Effects of Body Mass Index on Second-Trimester Amniotic Fluid Cytokine and Matrix Metalloproteinase Levels

Aim: The aim of this study was to determine the effects of obesity on amniotic fluid (AF) inflammatory markers in second-trimester AF, testing the hypothesis that there is a relationship between maternal body mass index (BMI) and fetal inflammatory exposure. Methods: AF was obtained from 84 singleton pregnant women undergoing elective amniocentesis for karyotype analysis at 16-24 weeks of gestation between April 2014 and May 2016. The cell-free AF was used to analyze interleukin (IL)-1β and IL-6, and matrix metalloproteinase (MMP)-1, MMP-6, and MMP-13. Results: IL-1β levels were significantly higher in class II-III obese patients than in class I obese, overweight, and normal weight patients (14.68 ± 1.37 vs. 13.34 ± 1.86 vs. 13.00 ± 2.22 vs. 10.78 ± 1.92, respectively; p < 0.05). IL-6 levels were lowest in the normal weight group and highest in class II-III obese patients. MMP-1, MMP-6, and MMP-13 levels were also significantly higher in class II-III obese patients than in the other groups. Conclusion: This study demonstrated that the fetuses of class II-III obese women are exposed in utero to higher cytokine and MMP levels than fetuses of lean women. Modification of current cutoff levels of intra-amniotic cytokines and MMPs according to the BMI could improve the accuracy of the prenatal diagnosis of intra-amniotic infection and inflammation.

Males are from Mars, and females are from Venus: sex-specific fetal brain gene expression signatures in a mouse model of maternal diet-induced obesity

Maternal obesity is associated with adverse neurodevelopmental outcomes in children, including autism spectrum disorders, developmental delay, and attention-deficit hyperactivity disorder. The underlying mechanisms remain unclear. We previously identified second-trimester amniotic fluid and term cord blood gene expression patterns suggesting dysregulated brain development in fetuses of obese compared with lean women. We sought to investigate the biological significance of these findings in a mouse model of maternal diet-induced obesity. We evaluated sex-specific differences in fetal growth, brain gene expression signatures, and associated pathways. Female C57BL/6J mice were fed a 60% high-fat diet or 10% fat control diet for 12-14 weeks prior to mating. During pregnancy, obese dams continued on the high-fat diet or transitioned to the control diet. Lean dams stayed on the control diet. On embryonic day 17.5, embryos were weighed and fetal brains were snap frozen. RNA was extracted from male and female forebrains (10 per diet group per sex) and hybridized to whole-genome expression arrays. Significantly differentially expressed genes were identified using a Welch's t test withthe Benjamini-Hochberg correction. Functional analyses were performed using ingenuity pathways analysis and gene set enrichment analysis. Embryos of dams on the high-fat diet were significantly smaller than controls, with males more severely affected than females (P= .01). Maternal obesity and maternal obesity with dietary change in pregnancy resulted in significantly more dysregulated genes in male vs female fetal brains (386 vs 66, P < .001). Maternal obesity with and without dietary change in pregnancy was associated with unique brain gene expression signatures for each sex, with an overlap of only 1 gene. Changing obese dams to a control diet in pregnancy resulted in more differentially expressed genes in the fetal brain than maternal obesity alone. Functional analyses identified common dysregulated pathways in both sexes, but maternal obesity and maternal dietary change affected different aspects of brain development in males compared with females. Maternal obesity is associated with sex-specific differences in fetal size and fetal brain gene expression signatures. Male fetal growth and brain gene expression may be more sensitive toenvironmental influences during pregnancy. Maternal diet during pregnancy has a significant impact on the embryonic brain transcriptome. It is important toconsider both fetal sex and maternal diet when evaluating the effects ofmaternal obesity on fetal neurodevelopment.

Elevated placenta growth factor levels in the early second-trimester amniotic fluid are associated with preterm delivery

Objective: The purpose of this study was to determine how angiogenesis-related factors correlate with preterm delivery.Methods: A cohort of 382 pregnant women undergoing early second-trimester genetic amniocentesis was enrolled and followed-up until delivery, and the amniotic fluid was collected and stored as a nested case-control study. Cases with preterm delivery (n = 31) were compared with matched controls with term delivery (n = 62). The amniotic fluid concentrations of placenta growth factor (PlGF), angiogenins, angiopoietin-2, soluble fms-like tyrosine kinase and soluble endoglin were determined using enzyme-linked immunosorbent assays.Results: Women who delivered preterm had a higher amniotic PlGF concentration compared with the control group (median 12.6 pg/ml versus 6.1 pg/ml; p=0.027). Other angiogenesis-related factors did not show any differences between case and control groups. The odds ratio for preterm delivery based on amniotic fluid PlGF was 1.031 (95% confidence interval: 1.002–1.061; p=0.035). Additionally, when the cases were subdivided into early preterm, late preterm and term groups, PlGF values between the early preterm and term delivery groups were significantly different (median 16.6 pg/ml versus 6.1 pg/ml; Bonferroni-adjusted p=0.018).Conclusion: Amniotic fluid PlGF levels in the early second trimester of pregnancy are associated with preterm delivery.

Clinical and cytogenetic results of a series of amniocentesis cases from Northeast China: a report of 2500 cases.

The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.

Complement Split Products in Amniotic Fluid in Pregnancies Subsequently Developing Early-Onset Preeclampsia.

Objective. To determine the second-trimester amniotic fluid concentrations of complement split products in pregnancies subsequently affected by early-onset preeclampsia. Study Design. Cohort of 731 women with singleton pregnancies undergoing second-trimester genetic amniocentesis followed up to delivery and analyzed as a nested case-control study. Cases of preeclampsia developing before 34 weeks' gestation (n = 15) were compared with 47 uncomplicated term controls. Amniotic fluid collected at amniocentesis was tested for complement split products Bb, C4a, C3a, and C5a. Results. Women who developed early-onset preeclampsia as compared with the term pregnant controls had significantly higher (P = 0.04) median amniotic fluid C3a levels (318.7 ng/mL versus 254.5 ng/mL). Median amniotic fluid Bb levels were also significantly higher (P = 0.03) in preeclamptic women than in normal pregnant women (1127 ng/mL versus 749 ng/mL). Median levels of C4a and C5a were not significantly different between the groups. Conclusion. Our data suggest that complement activation in early pregnancy is associated with early-onset preeclampsia. We believe this to be the first prospective study to link complement activation in amniotic fluid in early pregnancy and later development of preeclampsia. Our findings provide evidence that immune dysregulation may precede the clinical manifestations of preeclampsia and that the alternative complement pathway is principally involved.

Amniotic fluid phthalate levels and male fetal gonad function.

Prenatal exposure to phthalates may pose a threat to human male reproduction. However, additional knowledge about the in vivo effect in humans is needed, and reported associations with genital abnormalities are inconclusive. We aimed to study prenatal di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DiNP) exposure in relation to cryptorchidism, hypospadias, and human fetal Leydig cell function. We studied 270 cryptorchidism cases, 75 hypospadias cases, and 300 controls. Second-trimester amniotic fluid samples were available from a Danish pregnancy-screening biobank (n = 25,105) covering 1980-1996. We assayed metabolites of DEHP and DiNP (n = 645) and steroid hormones (n = 545) by mass spectrometry. We assayed insulin-like factor 3 by immunoassay (n = 475) and analyzed data using linear or logistic regression. Mono(2-ethyl-5-carboxypentyl) phthalate (5cx-MEPP, DEHP metabolite) was not consistently associated with cryptorchidism or hypospadias. However, we observed an 18% higher (95% confidence interval [CI] = 5%-33%) testosterone level, and a 41% lower (-56% to -21%) insulin-like factor 3 level in the highest 5cx-MEPP tertile compared with the lowest. Mono(4-methyl-7-carboxyheptyl) phthalate (7cx-MMeHP, DiNP metabolite) showed elevated odds ratio point estimates for having cryptorchidism (odds ratio = 1.28 [95% CI = 0.80 to 2.01]) and hypospadias (1.69 [0.78 to 3.67]), but was not consistently associated with the steroid hormones or insulin-like factor 3. Data on the DEHP metabolite indicate possible interference with human male fetal gonadal function. Considering the DiNP metabolite, we cannot exclude (nor statistically confirm) an association with hypospadias and, less strongly, with cryptorchidism.

119: Early evidence for increased complement activation in the amniotic fluid of women subsequently developing early-onset preeclampsia

There has been accumulating evidence that activation of the complement system is important in the pathogenesis of preeclampsia and that this effect is more pronounced in early-onset than in late-onset disease. Our aim was to determine the second-trimester amniotic fluid concentrations of complement split products in pregnancies subsequently affected by early-onset preeclampsia. We focused on amniotic fluid in order to better reflect processes operant at the fetal-maternal interface.