Dynamic thiol/disulphide homeostasis and ischemic modified albumin levels in isolated oligohydramnios.

OBJECTIVE: Oligohydramnios is defined as amniotic fluid index in ultrasonographic measurement is less than 5 percentile according to gestational age, the amniotic fluid volume is ≤ 5 cm, or if the single deepest dial is < 2 cm. The condition of oligohydramnios that not with fetal structural/chromosomal abnormalities, intrauterine growth retardation, intrauterine infection and maternal disease is described as isolated oligohydramnios (IO). The aim of this study is to examine whether oxidative stress and reactive oxygen species (ROS) have a place in the pathophysiology of IO. MATERIALS AND METHODS: In this prospective case-control study, a total of 126 participants were included. The patient group consisted of 65 patients who were diagnosed IO, and the control group consisted of 61 healthy normal pregnants. Native thiol (-SH), total thiol (-SH + -SS), dynamic disulfide (-SS), IMA values from maternal serum were measured and compared between groups. RESULTS: Maternal serum -SH and -SH + -SS values were significantly lower in the IO group than in the control group (409.47 ± 55.36 µmol/L vs. 437.40 ± 48.68 µmol/L, p = 0.03 and 457.40 ± 63.01 µmol/L vs. 484.59 ± 52.75 µmol/L, p = 0.01). In the IO group when -SS/-SH and -SS/-SH + -SS ratio was found to be statistically significantly higher than control group (5.84 ± 1.1 vs 5.41 ± 0.71, p = 0.01 and 5.2 ± 0.88 vs 4.8 ± 0.58, p = 0.01), -SH/-SH + -SS ratio was significantly lower (89.56 ± 1.7 vs 90.24 ± 1.16, p = 0.01). There was no significant difference in terms of -SS value (p = 0.66). IMA value was significantly higher in the IO group than control group (0.76 ± 0.10 ABSU vs 0.68 ± 0.06, p < 0.01). It is seen as a result of ROC analysis that -SH, -SH + -SS, -SS/-SH, -SS/-SH + -SS, -SH/-SH + -SS and IMA values have a diagnostic value for IO (p < 0.05). CONCLUSION: The thiol/disulfide balance shifted towards oxidative stress in IO compared to control group. So oxidative stress and ROS have a place in the pathophysiology of IO.

LncRNA and transcriptomic analysis of fetal membrane reveal potential targets involved in oligohydramnios.

BACKGROUND: The multiple causes of oligohydramnios make it challenging to study. Long noncoding RNAs (lncRNAs) are sets of RNAs that have been proven to function in multiple biological processes. The purpose of this study is to study expression level and possible role of lncRNAs in oligohydramnios. METHODS: In this study, total RNA was isolated from fetal membranes resected from oligohydramnios pregnant women (OP) and normal amount of amniotic fluid pregnant women (Normal). LncRNA microarray was used to analyze the differentially expressed lncRNAs and mRNAs. Kyoto Encyclopedia of Genes and Genomes (KEGG) was used to analyze the main enrichment pathways of differentially expressed mRNAs. Real-time quantitative PCR (qPCR) was used to validate the lncRNA expression level. RESULTS: LncRNA microarray analysis revealed that a total of 801 lncRNAs and 367 mRNAs were differentially expressed in OP; in these results, 638 lncRNAs and 189 mRNAs were upregulated, and 163 lncRNAs and 178 mRNAs were downregulated. Of the lncRNAs, 566 were intergenic lncRNAs, 351 were intronic antisense lncRNAs, and 300 were natural antisense lncRNAs. The differentially expressed lncRNAs were primarily located in chromosomes 2, 1, and 11. KEGG enrichment pathways revealed that the differentially expressed mRNAs were enriched in focal adhesion as well as in the signaling pathways of Ras, tumor necrosis factor (TNF), estrogen, and chemokine. The qPCR results confirmed that LINC00515 and RP11-388P9.2 were upregulated in OP. Furthermore, the constructed lncRNA-miRNA-mRNA regulatory network revealed tenascin R (TNR), cystic fibrosis transmembrane conductance regulator (CFTR), ATP-binding cassette sub-family A member 12 (ABCA12), and collagen 9A2 (COL9A2) as the candidate targets of LINC00515 and RP11-388P9.2. CONCLUSIONS: In summary, we revealed the profiles of lncRNA and mRNA in OP. These results might offer potential targets for biological prevention for pregnant women with oligohydramnios detected before delivery and provided a reliable basis for clinical biological treatment in OP.

Is pregnancy associated plasma protein-A (PAPP-A) a marker for adverse perinatal outcomes in preterm isolated oligohydramnios cases?

OBJECTIVE: Isolated oligohydramnios is defined as an amniotic fluid index below five centimeter with no other coexisting condition. There are still controversies about the management and pregnancy outcomes. A marker predicting these is crucial. Low pregnancy associated plasma protein-A levels were reported to be related with adverse pregnancy outcomes. We aimed to determine the role of first trimester pregnancy associated plasma protein-A for poor outcomes in preterm isolated oligohydramnios cases. MATERIAL AND METHODS: Fifty-one patients with singleton pregnancies diagnosed as isolated oligohydramnios at 28/0-36/6 weeks of gestation and 110 gestational age matched healthy controls between January and December 2015 were included. Maternal age, gestational age at delivery, mode of delivery, indication for cesarean section, Apgar scores at first and fifth minutes, birth weight, neonatal intensive care unit admission and mortality were recorded. Pregnancy associated plasma protein-A levels were compared between groups and its role in adverse perinatal outcomes was evaluated. RESULTS: Pregnancy associated plasma protein-A levels and pregnancy outcomes were similar in two groups (p > 0.050) except birth weight, gestational age at delivery and presence of fetal distress. Pregnancy associated plasma protein-A levels did not differ in terms of delivery mode, presence of fetal distress, first and fifth minutes Apgar scores and neonatal intensive care unit admission (p = 0.323,0.650,0.990,0.112,0.853). Also, it was not determined as a risk factor for cesarean section, presence of fetal distress, low Apgar scores and neonatal intensive care unit admission. CONCLUSION: Pregnancy associated plasma protein-A, a well-known prognostic factor for some of high risk pregnancy conditions, may not be used as a marker in preterm isolated oligohydramnios cases.

Is unexplained elevated maternal serum alpha-fetoprotein still important predictor for adverse pregnancy outcome?

OBJECTIVES: The purpose of this study was to determined the predictive value of maternal serum alpha-fetoprotein (MSAFP) as a marker for adverse pregnancy outcomes. MATERIAL AND METHODS: This study was carried out at Dr. Zekai Tahir Burak Women's Health Education and Research Hospital between 2009 and 2010. This study included a total of 1,177 pregnant women, including 170 in the study group and 1,007 in the control group. Pregnancy outcomes and characteristics were analyzed with regard to the MSAFP value. RESULTS: Gestational week, birth weight and APGAR scores were significantly lower in the elevated MSAFP group (p < 0.001). Adverse pregnancy outcomes, such as preterm delivery, preterm premature rupture of membranes (PPROM), oligohydramnios and intrauterine growth restriction (IUGR) rates were increased in the elevated MSAFP group. CONCLUSIONS: Although ultrasound outweighs as a screening method for neural tube defects and non-invasive prenatal testing outweighs for aneuploidy screening MSAFP level in the second trimester is still an important predictor for poor maternal/fetal outcomes.

Revisiting the role of first trimester homocysteine as an index of maternal and fetal outcome.

AIM. To revisit the role of first trimester homocysteine levels with the maternal and fetal outcome. METHODS. This was a cohort study comprising 100 antenatal women between 8 and 12 weeks of gestation. Serum homocysteine levels were checked after overnight fasting. RESULTS. There were significantly elevated homocysteine levels among women with prior history of hypertensive disorders of pregnancy and prior second or third trimester pregnancy losses. There was no significant difference in homocysteine levels among women with previous gestational diabetes mellitus, preterm deliveries, or fetal malformations. Homocysteine levels were significantly elevated in those who developed hypertensive disorder of pregnancy, oligohydramnios, and meconium stained amniotic fluid, had a pregnancy loss, or delivered a low birth weight baby. There was no significant difference in homocysteine levels for those who developed gestational diabetes mellitus. CONCLUSIONS. Increased first trimester serum homocysteine is associated with history of pregnancy losses, hypertensive disorders of pregnancy, and preterm birth. This is also associated with hypertensive disorders of pregnancy, pregnancy loss, oligohydramnios, meconium stained amniotic fluid, and low birth weight in the current pregnancy. This trial is registered with ClinicalTrials.gov CTRI/2013/02/003441.

The association between second-trimester maternal serum alpha-fetoprotein in 14-22 weeks and adverse pregnancy outcome.

Aim of this study is to determine the risk of adverse pregnancy outcome by maternal serum alpha-fetoprotein (MSAFP) level. We followed 295 pregnant women from MSAFP screening in the 14th to 22th week of gestation until the end of pregnancy and information on pregnancy outcome have been recorded in questionnaires. Of 295 pregnant women, 270 had term labor and 25 had preterm labor. The frequencies of pregnancy outcomes were as following: 3 (1.01%) stillbirths, 25 (8.47%) preterm labor, and 10 (3.4%) preterm rupture of membranous (PROM), 15 (5.1%) pre-eclampsia, 23 (7.8%) oligohydramnious, and 1 (0.33%) miscarriage. The mean of preterm labor was significantly associated with the higher level of MSAFP (P = 0.021). The mean was 55.1 ng/cc in preterm labor and 41.1 ng/cc in term labor. Also, second trimester MSAFP levels were higher in women with pre-eclampsia (P < 0.001). The significant association was found between higher level of MSAFP with oligohydramnious (P < 0.001) and low birth weight (P < 0.001). Pregnancies with an elevated MSAFP level are associated with adverse obstetric outcomes and need more prenatal care.

Double aneuploidy involving trisomy 7 with Potter sequence.

We report a prenatal case of double aneuploidy (consisting of chromosome 7 and X) with the features of Potter sequence. Of the stillborn fetus, skin fibroblast cultures were performed and fluorescence in situ hybridization (FISH) technique was also used for further investigation. On physical examination; the fetus was found to have malformed ears, micrognatia, hypertelorism, abnormal extremities, rocker-bottom feet and abnormal external genitalia and polycystic right kidney was seen after an extensive autopsy. As amniocentesis and cordocentesis materials revealed X chromosome mosaicism, trisomy 7 was detected in the skin fibroblast culture of the ex fetus and karyotype evaluated as composite; 46~47,X,+7,-X[cp18]. FISH results confirmed the double aneuploidy and also revealed XX and XXXX cell lines. Comparison with the previously reported cases of trisomy 7 with Potter syndrome suggests a possible link (if not coincidental) between trisomy 7 and Potter syndrome in our case. This is the first reported case of double aneuploidy involving trisomy 7 with the features of Potter syndrome.

[Levels of Cd, Pb in blood and Zn, Cu, Cd, Pb in amniotic fluid of tobacco smoking women during pregnancy complicated oligohydramnios or premature rupture of membranes]. / Poziom metali Cd i Pb we krwi oraz Zn, Cu, Cd i Pb w wodach plodowych kobiet palacych papierosy podczas ciazy powiklanej malowodziem lub przedwczesnym odplywaniem wód plodowych.

OBJECTIVES: The ingredients of tobacco smoke have the impact on uterine blood vessels. They caused vascular insufficiency of placenta during development of gestation and changes in placental tissue and fetal membranes. It manifest changeable metal permeability and others symptoms. DESIGN: Assessment of metal contents in blood and amniotic fluid in pregnancies with oligohydramnios and PROM. MATERIALS AND METHODS: The materials for studies were blood and amniotic fluid of 30 pregnancies. All of them had made amino-punction between 20 and 38 week of pregnancy before procedure of amniotic fluid supplementation. 15 patients had diagnosed oligohydramnios and the next 15 women had diagnosed premature rupture of membranes. Metals were determined by method of electrothermal atomical absorbic spectrophotometry (ET-ASA). RESULTS AND CONCLUSIONS: Twice lower concentration of Zn and Cd and ten times lower concentration of Pb in amniotic fluids in examined women than women in normal pregnancy were observed. The women, with oligohydramnios in earlier period of gestation, smoked many more cigarettes and cotinine++ and Cd. were much higher. Both these facts had relevance with each other certainly. The stillborns were many more in this group. The different distribution of Cd, Pb, Zn in pregnant women with PROM and oligohydramnios, comparing with women in normal pregnancy was demonstrated. It is probable to be effect of placental tissue and fetal membranes disfunction.

Utility of the triple test in the detection of abnormalities of the feto-placental unit.

INTRODUCTION: The objective of the study was to examine the relationship between the concentrations of maternal serum AFP, total beta-hCG and uE3 and the presence of various pathologies of the feto-placental unit. MATERIAL AND METHODS: The triple test was performed in the group of 882 pregnant women between the 14th and 21st week of gestation. The control group consisted of 863 pregnant women with unburdened obstetric anamnesis with an uneventful singleton pregnancy. The examined group consisted of 19 pregnant women with fetal aneuploidies and other pathologies of the feto-placental unit (oligohydramnios, vacuolization of the trophoblast). In the maternal sera concentrations of AFP, total beta-hCG and unconjugated estriol were determined. The risk of fetal trisomy 21 was calculated using DOWNS and PRISCA 3.0 software (cut-off 1: 295), Ulm Index was also calculated (cut-off 8.1). RESULTS: In the group of pregnant women with fetal chromosomal aneuploidies no significant changes of the examined parameters were established. In the cases of oligohydramnios AFP concentrations significantly increased, in the cases of fetal triploidy the concentrations of all examined parameters decreased. In the cases of vacuolization of the trophoblast concentration of the total beta-hCG increased. CONCLUSION: Oligohydramnios, fetal triploidy and vacuolization of the trophoblast caused significant changes of the concentrations AFP, total beta-hCG and unconjugated estriol in maternal sera.

Second-trimester maternal serum marker screening: maternal serum alpha-fetoprotein, beta-human chorionic gonadotropin, estriol, and their various combinations as predictors of pregnancy outcome.

OBJECTIVE: We evaluated the value of all 3 common biochemical serum markers, maternal serum alpha-fetoprotein, beta-human chorionic gonadotropin, and unconjugated estriol, and combinations thereof as predictors of pregnancy outcome. STUDY DESIGN: A total of 60,040 patients underwent maternal serum screening. All patients had maternal serum alpha-fetoprotein measurements; beta-human chorionic gonadotropin was measured in 45,565 patients, and 24,504 patients had determination of all 3 markers, including unconjugated estriol. The incidences of various pregnancy outcomes were evaluated according to the serum marker levels by using clinically applied cutoff points. RESULTS: In confirmation of previous observations, increased maternal serum alpha-fetoprotein levels (>2.5 multiples of the median) were found to be significantly associated with pregnancy-induced hypertension, miscarriage, preterm delivery, intrauterine growth restriction, intrauterine fetal death, oligohydramnios, and abruptio placentae. Increased beta-human chorionic gonadotropin levels (>2.5 multiples of the median [MoM]) were significantly associated with pregnancy-induced hypertension, miscarriage, preterm delivery, and intrauterine fetal death. Finally, decreased unconjugated estriol levels (<0.5 MoM) were found to be significantly associated with pregnancy-induced hypertension, miscarriage, intrauterine growth restriction, and intrauterine fetal death. As with increased second-trimester maternal serum alpha-fetoprotein levels, increased serum beta-human chorionic gonadotropin and low unconjugated estriol levels are significantly associated with adverse pregnancy outcomes. These are most likely attributed to placental dysfunction. CONCLUSION: Multiple-marker screening can be used not only for the detection of fetal anomalies and aneu-ploidy but also for detection of high-risk pregnancies.

Fetal acidemia in the absence of fluid observed at amniotomy.

The objective of this study was to determine the rate of pathological fetal acidemia in the absence of fluid observed at amniotomy. Thirty-nine consecutive patients with no fluid observed at the time of amniotomy were prospectively enrolled in this study. Ultrasound measurement of amniotic fluid index was performed. Umbilical cord gases were performed on arterial and venous samples at the time of delivery. Patient name and medical record number were noted and delivery data were extracted from review of the medical record. The median gestational age at admission was 41 weeks (range 38 to 42 weeks). Sixteen patients (41%) were subsequently noted to have meconium at the time of delivery. The median amniotic fluid index was 2.0 cm with a range of 0 to 9.0 cm. Thirty patients (76.9%) had an amniotic fluid index of less than 5.0 cm. The median umbilical artery pH in this patient population was 7.21 with a range of 6.75 to 7.42. Only one infant had an umbilical artery pH less than 7.00. The rate of cesarean section for documented fetal distress was 2.6%. The absence of observed fluid at amniotomy, while commonly associated with subsequent meconium at delivery, is not predictive of fetal acidemia or operative delivery for fetal distress.

Fetal hemoglobin changes in the twin oligohydramnios-polyhydramnios sequence.

Fetal hemoglobin concentration was measured in each twin from five monochorionic pregnancies complicated by twin-to-twin transfusion, diagnosed by growth discordance and coexistent oligohydramnios-polyhydramnios. In three cases the hemoglobin concentration of the smaller twin with oligohydramnios was lower than the normal mean for gestation, and the hemoglobin difference was more than 5 g/dl in two of these cases. In the other two cases, the hemoglobin concentration of the four fetuses with coexistent oligohydramnios-polyhydramnios was within the normal range. This suggests that twin-to-twin transfusion may occur without hemoglobin changes, or that alternatively coexistent oligohydramnios-polyhydramnios occurs in the absence of twin-to-twin transfusion.

Treatment of oligohydramnios with maternal 1-deamino-[8-D-arginine] vasopressin-induced plasma hypoosmolality.

OBJECTIVE: Maternal 1-deamino-[8-D-arginine] vasopressin (a selective antidiuretic agonist) and oral water loading decrease maternal and fetal plasma osmolality and markedly increase fetal urine flow in sheep. We hypothesized that a titrated reduction in maternal plasma osmolality would increase human amniotic fluid volume. STUDY DESIGN: Pregnant women (n = 5) with oligohydramnios at term were administered oral water loading (20 ml/kg) and intravenous 1-deamino-[8-D-arginine] vasopressin (2 micrograms) to induce antidiuresis. Maternal plasma and urine osmolality and urine production were measured hourly, and water replacement was titrated for 8 hours to reduce plasma osmolality by 15 to 20 mOsm/kg. The amniotic fluid index determined by ultrasonography was measured at baseline, 8 hours, and 24 hours. A control group of pregnant women (n = 5) with oligohydramnios at term was observed for 8 hours with maintenance intravenous hydration. RESULTS: In 1-deamino-[8-D-arginine] vasopressin-treated women, maternal urine flow increased with oral water loading, decreased with 1-deamino-[8-D-arginine] vasopressin administration, and remained reduced for 8 hours. Maternal plasma osmolality significantly decreased (285 +/- 4 to 265 +/- 4 mOsm/kg) and the amniotic fluid index significantly increased (4.1 +/- 0.6 to 8.2 +/- 1.5 cm) at 8 hours. Although maternal urine osmolality returned to basal values at 24 hours, plasma osmolality was reduced and the amniotic fluid index remained significantly increased (8.2 +/- 1.3 cm). There was no change in the amniotic fluid index (4.3 +/- 0.4 to 4.7 +/- 0.7 cm) in control patients observed with maintenance intravenous hydration. CONCLUSIONS: Maternal 1-deamino-[8-D-arginine] vasopressin and oral water administration can reduce and stabilize plasma osmolality and increase amniotic fluid volume. 1-Deamino-[8-D-arginine] vasopressin therapy has potential for the prevention and treatment of oligohydramnios.

Acute maternal hydration in third-trimester oligohydramnios: effects on amniotic fluid volume, uteroplacental perfusion, and fetal blood flow and urine output.

OBJECTIVE: Our purpose was to determine whether acute maternal hydration in pregnancies with third-trimester oligohydramnios (1) increases amniotic fluid index and hourly fetal urine production rate and (2) alters uteroplacental perfusion and fetal blood flow. STUDY DESIGN: Ten women with third-trimester oligohydramnios (amniotic fluid index < or = 5 cm) and 10 controls with normal amniotic fluid volume (amniotic fluid index > 7 cm) were prospectively recruited for this study. Maternal plasma and urine osmolality, amniotic fluid index, hourly fetal urine production rate, and Doppler flow velocimetry of maternal uterine artery and fetal umbilical, descending aorta, middle cerebral, and renal arteries were determined before and after oral hydration by having the patient drink 2 L of water over 2 hours. RESULTS: There was a significant reduction in maternal plasma (p < 0.05) and urine osmolality (p < 0.0001) in both groups after short-term oral hydration. Hydration increased amniotic fluid volume in women with oligohydramnios (mean change in amniotic fluid index 3.2 cm, 95% confidence intervals 1.1 to 5.3; p < 0.02) but not in those with normal amniotic fluid volume (mean change in amniotic fluid index -2.0, 95% confidence intervals -4.1 to +0.2). The hourly fetal urine production rate, however, did not increase in either group (mean change in hourly fetal urine production rate 3.5 ml/hr, 95% confidence intervals -11.7 to +18.7 and -6.8 ml/hr, 95% confidence intervals -2.9 to -10.7, respectively). Hydration was associated with an increase in uterine artery mean velocity in the oligohydramnios group (mean change in mean velocity 16.7 cm/sec, 95% confidence intervals 8.0 to 25.3; p < 0.006) but not in controls (mean change in mean velocity 1.2 cm/sec, 95% confidence intervals -19.7 to +22.1). There was no change in pulsatility index or in velocity in any of the fetal vessels studied in either group. CONCLUSIONS: Short-term maternal oral hydration increases the amniotic fluid index in women with third-trimester oligohydramnios. Although the mechanism for this effect remains unclear, it could not be accounted for by fetal urination in this study but instead was associated with improved uteroplacental perfusion.

Effects of viral virulence on intrauterine growth in SIV-infected fetal rhesus macaques (Macaca mulatta).

Studies with a simian immunodeficiency virus (SIV)-infected fetal monkey model were conducted with a focus on fetal growth and viral pathogenesis. Twenty-six fetuses were inoculated in utero via ultrasound guidance with an uncloned pathogenic strain of SIV or vehicle during the second or third trimesters [gestational day (GD) 65, 110, or 130], sonographically monitored weekly (biometrics, blood flow), then necropsied at incremental time points postinfection. Peripheral blood hematologic (complete blood counts, clinical chemistries), immunologic (immunophenotyping), and endocrine studies [insulin-like growth factor (IGF), IGF-binding proteins (IGFBP)] were conducted. Severe intrauterine growth restriction (IUGR), oligohydramnios, and altered lymphocyte counts were noted for fetuses infected on GD 65. Less severe effects were detected for fetuses inoculated at the later time points, with severity dependent upon the length of SIV infection in utero. IGF studies indicated significant reductions in IGF-I and elevated immunoreactive levels of IGFBP-3 in infected fetuses during the third trimester. Parallel studies conducted with four fetuses infected on GD 65 with a nonpathogenic, molecularly cloned virus (SIVmac1A11) resulted in normal fetal growth, with no effects on hematopoiesis or IGF/IGFBP levels, and no evidence of clinical disease. Taken together, these studies show that (1) infection of fetuses during the early second trimester with an uncloned pathogenic strain of SIV results in severe IUGR and a disruption in the molar ratio of IGF:IGFBP-3, and (2) outcome of fetal SIV infection is determined by the timing of infection and the virulence of the viral inoculum.

Risk of anomalies as a function of level of elevated maternal serum alpha-fetoprotein.

OBJECTIVE: Most neural tube defects risks are not actual but mathematical extrapolations. We sought to evaluate this risk and to compare actual performance. STUDY DESIGN: This was a retrospective study of a referral population with elevated maternal serum alpha-fetoprotein results between 1987 and 1992. Ultrasonography results, delivery records, and autopsy results were compared with entry levels of maternal serum alpha-fetoprotein, and the percentage of fetal anomalies detected in this study was evaluated. RESULTS: A total of 773 patients with elevated maternal serum alpha-fetoprotein levels were evaluated. There was a progressive increase in the incidence of anomalies as a direct function of the level of the maternal serum AFP, varying from 3.4% at a level of 2.5 to 40.3% at a level > 7.0. CONCLUSION: Data from this study support the correlation of maternal serum AFP levels with the risk of neural tube defect and ventral wall defects.

Maternal serum markers in second-trimester oligohydramnios.

The levels of the maternal serum markers alpha-fetoprotein (AFP), human chorionic gonadotrophin (hCG), and unconjugated oestriol (uE3) in 35 pregnant women with early second-trimester oligohydramnios differed from those in a reference population of 1699 singleton pregnancies. Maternal serum AFP levels above the 95th centile of the population distribution were observed in 80 per cent (16/20) of oligohydramnios cases with a normal fetus and in only 20 per cent (3/15) of the cases with a fetus displaying urogenital tract malformations. Elevated levels of hCG (above the 95th centile) and decreased levels of uE3 (below the fifth centile) were encountered in 26 per cent (9/35) and 17 per cent (6/35) of the women, irrespective of the fetal condition. The abnormal profile of the serum markers in early second-trimester oligohydramnios resulted in 57 per cent (20 out of 35) of screen-positive cases for either fetal Down's syndrome or neural tube defects, compared with 8.4 per cent (143 out of 1699) in the reference population.

Maternal serum alpha-fetoprotein levels and fetal outcome in early second-trimester oligohydramnios.

Early second-trimester oligohydramnios was associated with normal maternal serum alpha-fetoprotein (MSAFP) levels in nine out of 26 cases (35 per cent). Congenital malformations of the fetal urinary tract resulting in fetal anuria were present in nine cases; in seven of them, normal MSAFP levels were measured. In contrast, normal MSAFP levels were established in only 2 out of the 17 cases without fetal malformations. These data suggest that fetal urine is the major source of elevated AFP in the maternal compartment in early second-trimester oligohydramnios. This is further supported by the lack of any relationship between concentrations of MSAFP non-reactive with Concanavalin A, originating mainly from the yolk sac-derived amniotic fluid AFP pool, and the presence of fetal diuresis. Three out of 26 women had experienced early second-trimester oligohydramnios in a previous pregnancy, suggesting the existence of a recurrence risk for this condition.

Multiple antepartum amnioinfusions in selected cases of oligohydramnios.

In general the perinatal outcome of oligohydramnios is poor. The diverse etiology of the entity is difficult to pinpoint. Multiple antepartum amnioinfusions can be beneficial in selected cases not associated with malformations, abnormal karyotypes or premature rupture of the membranes. We treated 38 patients with 105 such instillations.

Alpha-Fetoprotein and renal dysfunction of the fetus.

Alpha-fetoprotein (AFP) levels were measured in 25 pregnancies with renal dysfunction of the fetus. Oligohydramnios was found in 14 of 16 patients diagnosed by 20 weeks of gestation and in all of those diagnosed later. AFP levels in maternal serum were normal in 17 (68%), elevated in five (20%), and low in three patients (12%). AFP serum levels up to 24 weeks of gestation were significantly higher than after 24 weeks. AFP levels in amniotic fluid obtained from amniocentesis in six patients were normal or slightly elevated. We suggest that the concentration of AFP in amniotic fluid and maternal serum does not only depend on the physiologic proteinuria of the immature fetal kidneys but also on the permeability of the not yet keratinized fetal skin and the diluting volume of the amniotic fluid.