Elevation of macrophage colony-stimulating factor in amniotic fluid at late stage of normal pregnancy

PROBLEM: Macrophage colony-stimulating factor (M-CSF) promotes placental growth and maintenance, and regulates trophoblast invasion into the placental bed. We evaluated whether the amniotic fluid M-CSF levels at the late stage of normal pregnancy is altered compared with those at the middle stage. METHOD OF STUDY: This study enrolled 52 subjects experiencing normotensive pregnancies with single fetuses, of whom 26 were women at the late stage (term gravidas) and 26 were women at the middle stage (controls). The average gestational age at entry was 38 weeks of gestation and 17 weeks, respectively. Amniotic fluid was collected from these subjects. Amniotic fluid M-CSF levels were determined by the enzyme-linked immunosorbent assay method then compared between term gravidas and controls. RESULTS: Amniotic fluid M-CSF concentrations were 4815 pg/mL (median) in term gravidas and 3795 pg/mL in controls; the concentrations were significantly higher in term gravidas than in controls. CONCLUSIONS: We demonstrated a significant increase in amniotic fluid M-CSF levels in term gravidas. These results suggest that elevated levels of M-CSF in amniotic fluid have an important immunological function in the maintenance of pregnancy and fetal growth.     

Midtrimester Amniotic Fluid Tumor Necrosis Factor-Alpha Does Not Predict Small-for-Gestational-Age Infants

PROBLEM: To evaluate the independent ability of midtrimester amniotic fluid tumor necrosis factor-alpha (TNF-α) in the prediction of small-for-gestational-age (SGA) infants. METHOD OF STUDY: In this case-control study, patients delivering a SGA infant were matched with controls based on GA at delivery, maternal age, race, and parity. Patients with immune disease, chronic hypertension, diabetes, asthma, congenital hearts disease, multiple gestation, and fetal anomalies were excluded. Amniotic fluid samples were immunoassayed for TNF-α. Potential confounding variables evaluated were maternal serum alpha-fetoprotein level, smoking history, pregnancy induced hypertension, and neonatal gender. Statistical analysis included Fisher's exact test and ANOVA after log transformation with P < 0.05 considered significant. RESULTS: Eighteen patients delivered SGA neonates and were matched with 41 controls. No significant differences were identified in the confounding variables between patients with SGA neonates and controls. Amniotic fluid TNF-α levels were not significantly different between patients subsequently delivering SGA neonates and controls [median 7.63 (range 0.25-16.1) pg/mL versus 9.39 (0.25–66.9) pg/mL, P = 0.8]. CONCLUSIONS: Midtrimester amniotic fluid TNF-α levels are not predictive of SGA neonates when compared with controls matched for gestational age at delivery.     

Hepatocyte growth factor concentration in the early second-trimester amniotic fluid does not predict fetal growth at birth.

The purpose of this study was to evaluate whether hepatocyte growth factor (HGF) concentrations in the early second-trimester amniotic fluid predict fetal growth at birth. HGF and insulin-like growth factor-I (IGF-I) concentrations in the early second-trimester amniotic fluid were measured in 12 pregnancies with small for gestational age (SGA) infants, 84 pregnancies with appropriate for gestational age (AGA) infants, and eight pregnancies with large for gestational age (LGA) infants. HGF concentrations were measured from the early second-trimester amniotic fluid samples using an enzyme-linked immunosorbent assay. IGF-I concentrations were measured from the early second-trimester amniotic fluid samples using an immunoradiometric assay. Maternal age in AGA group (34.2 +/- 5.5 years) was significantly lower than in SGA (37.9 +/- 3.0 years) and LGA (37.6 +/- 3.3 years) groups (P < 0.05). There were no significant differences for parity or gestational age at amniocentesis among the groups. There were significant differences for birth age, birth weight, neonatal height, and placental weight among the groups (P < 0.05). HGF concentrations in SGA, AGA and LGA groups were 16.9 +/- 6.6, 16.7 +/- 9.0 and 20.2 +/- 14.8 ng/ml respectively (not significant). There was no correlation between amniotic fluid HGF concentrations and birth weight, height or placental weight. There were also no significant differences for amniotic fluid IGF-I concentrations among the three groups. These results suggest that differences in HGF concentrations in the early second-trimester amniotic fluid do not predict fetal growth at birth. Further study is needed to clarify the role of high HGF concentrations in early second-trimester amniotic fluid during pregnancy.     

Macrophage colony-stimulating factor levels in amniotic fluid before and after the onset of labor do not differ in normal pregnancies

PROBLEM: Macrophage colony-stimulating factor (M-CSF) promotes placental growth and maintenance. M-CSF also regulates trophoblast invasion into the placental bed. We evaluated whether M-CSF levels in amniotic fluid during labor contributing to subsequent delivery differed from those before the onset of labor in normal pregnancies. METHOD OF STUDY: This study enrolled 48 Japanese women experiencing normal pregnancies with single fetuses who had no infection. Of these pregnancies, 24 were women during labor: 22 led to subsequent term delivery (labors); two had premature delivery. The other 24 were women without labor underwent cesarean section (controls). These two groups (22 labors and 24 controls) were compared. The average gestational age at entry was 38 weeks of gestation. The women's ages and gestational ages did not differ significantly between the two groups. Amniotic fluid was collected and the M-CSF levels were compared between two groups. The M-CSF level was determined by the sandwich enzyme-linked immunosorbent assay (ELISA) method. RESULTS: The levels of M-CSF in amniotic fluid did not differ significantly between the women during labor and those without labor. CONCLUSIONS: M-CSF in amniotic fluid may not contribute to the onset of labor in term pregnancy and/or labor resulting in subsequent delivery may not induce the production and secretion of M-CSF into amniotic cavity.     

Maternal and fetal nitric oxide synthesis is decreased in pregnancies with small for gestational age infants

Our purpose was to evaluate whether maternal and fetal nitric oxide synthesis in pregnancies with small for gestational age (SGA) infants are different from those in pregnancies with appropriate for gestational age (AGA) infants. Maternal and fetal circulating nitrate and nitrite concentrations were compared between 30 pregnancies with AGA and 10 pregnancies with SGA at birth. End-products of nitric oxide synthesis were measured in maternal and cord venous blood samples using a fluorometric assay. Umbilical artery blood pH and PO2 were also measured. Maternal circulating nitrite and nitrate concentrations (6.91 +/- 1.27 microM) in pregnancies with SGA were significantly lower than those (11.69 +/- 1.33 microM) in pregnancies with AGA (P = 0.015). Fetal circulating nitrite and nitrate concentrations (7.54 +/- 1.09 microM) in pregnancies with SGA were also significantly lower than those (11.24 +/- 1.08 microM) in pregnancies with AGA (P = 0.024). There were no significant differences in umbilical artery blood pH and PO2 between the two groups. These results suggest that maternal and fetal nitric oxide synthesis are decreased in pregnancies with SGA infants.      

Granulocyte-macrophage colony-stimulating factor levels in amniotic fluid before the onset of labor and during labor do not differ in normal pregnancies

PROBLEM: Granulocyte-macrophage colony-stimulating factor (GM-CSF) at the implantation site may regulate invasion and differentiation of placental trophoblast. We evaluated whether GM-CSF levels in amniotic fluid during labor contributing to subsequent delivery differed from those before the onset of labor in normal pregnancies. METHOD OF STUDY: This study enrolled 36 Japanese women experiencing normal pregnancies with single fetuses who had no infection. Of these pregnancies, 18 were women during labor that led to subsequent term delivery (labors). The other 18 were women without labor underwent cesarean section (controls). These two groups (18 labors and 18 controls) were compared. The average gestational age at entry was 38-39 weeks of gestation. The women's ages and gestational ages did not differ significantly between the two groups. Amniotic fluid was collected and the GM-CSF levels were compared between two groups. The GM-CSF level was determined by the enzyme-linked immunosorbent assay method. RESULTS: There was no significant increase in GM-CSF levels in amniotic fluid during labor compared with that before the onset of labor. CONCLUSIONS: The GM-CSF in amniotic fluid may not promote the onset of labor at term and/or term labor contributing to subsequent delivery may not induce the production and secretion of GM-CSF into amniotic cavity.     

Macrophage Inflammatory Protein-1α in Term and Preterm Parturtition: Effect of Microbial Invasion of the Amniotic Cavity

PROBLEM: This study was conducted to determine whether: (1) gestational age, parturition, and microbial invasion of the amniotic cavity (MIAC) are associated with changes in amniotic fluid concentrations of immunoreactive macrophage inflammatory protein-1α; (2) amniotic fluid concentrations of macrophage inflammatory protein-1α are correlated with the white blood cell count and the concentrations of interleukin-8 in amniotic fluid. METHOD: Amniotic fluid was retrieved by amniocentesis from 126 patients; 54 women with preterm labor and intact membranes (no MIAC-delivery at term, N = 21; no MIAC-preterm delivery, N = 16; MIAC-preterm delivery, N = 17); 62 patients at term (no labor, N = 19; labor-no MIAC, N = 20; labor-MIAC, N = 23); and 10 patients in the midtrimester of pregnancy. Amniotic fluid was cultured for aerobic, anaerobic and Mycoplasma species. Determinations of amniotic fluid macrophage inflammatory protein-1α and interleukin-8 were performed with immunoassays validated for amniotic fluid (sensitivity: 14.2 pg/ml and 0.3 ng/ml, respectively). Kruskal-Wallis analysis of variance (ANOVA) for censored data, Mann-Whitney U test and Spearman's rank correlation were performed for analysis. RESULTS: 1) Amniotic fluid macrophage inflammatory protein-1α was present in only 31.0% (9/29) of patients not in labor (midtrimester and term). 2) Patients with preterm labor and MIAC had higher amniotic fluid concentrations of macrophage inflammatory protein-1α than those without MIAC (no MIAC-delivery at term: median 0.0 pg/ml, range 0.0–221.2; no MIAC-preterm delivery: median 37.4 pg/ml, range 0.0–494.6; MIAC-preterm delivery: median 7171.0 pg/ml, range 402.5–37994.0; P<0.00001). 3) Among patients at term, MIAC was associated with higher concentrations of amniotic fluid macrophage inflammatory protein-1α than patients without MIAC (no labor: median 0.0 pg/ml, range 0.0–25.6; labor-no MIAC: median 16.7 pg/ml, range 0.0–161.6; labor-MIAC: median 103.8 pg/ ml, range 0.0–4349.0, P<0.001). 4) Among patients in preterm labor, a strong correlation was found between amniotic fluid concentrations of macrophage inflammatory protein-1α and interleukin-8 (r = 0.9, P<0.00001) and between amniotic fluid macrophage inflammatory protein-1α concentrations and amniotic fluid white blood cell count (r = 0.6, P<0.0001). CONCLUSIONS: (1) Macrophage inflammatory protein-1α is undetectable in most amniotic fluid samples from patients in the midtrimester of pregnancy and at term not in labor. (2) Microbial invasion of the amniotic cavity is associated with increased concentrations of immunoreactive amniotic fluid macrophage inflammatory protein-1α in both term and preterm gestations. (3) Amniotic fluid macrophage inflammatory protein-1α concentrations significantly correlate with interleukin-8 levels and white blood cell count in amniotic fluid. Our data strongly suggest a role for macrophage inflammatory protein-1α in the mechanisms responsible for the recruitment of leukocytes into the amniotic cavity during the course of intrauterine infection.     

Comparison of disaturated phosphatidylcholine and fetal lung maturity surfactant/albumin ratio in diabetic and nondiabetic pregnancies

We studied fetal lung maturity (FLM) by the amniotic fluid surfactant/albumin (FLM S/A) ratio and the disaturated phosphatidylcholine (DSPC) amniotic fluid levels at different gestational ages in diabetic (179 women with type 1 diabetes mellitus antedating pregnancy; infants delivered within 72 hours after amniotic fluid testing for DSPC level and FLM S/A ratio) and nondiabetic pregnancies (2 independent nondiabetic groups, 300 for FLM S/A ratio and 1,231 for DSPC level). The degree of maternal glycemia during gestation was estimated by serial measurements of hemoglobin A1. Multiple regression analyses, including gestational age (GAs) and diabetic status as independent variables and FLM S/A ratio and DSPC level as dependent variables, revealed significant effect from diabetic status and GA for FLM S/A ratio and a significant effect from GA but not from diabetic status for DSPC level. Glucose levels were controlled adequately throughout gestation as reflected by mean total glycated hemoglobin levels. Amniotic fluid levels of DSPC, the major surface tension-lowering component of pulmonary surfactant, are not significantly different between diabetic and nondiabetic pregnancies at different GAs.     

Decreased maternal circulating hepatocyte growth factor (HGF) concentrations in pregnancies with small for gestational age infants

Our purpose was to evaluate whether maternal and fetal hepatocytegrowth factor (HGF) concentrations in pregnancies with smallfor gestational age (SGA) infants are different from those inpregnancies with appropriate for gestational age (AGA) infants.Maternal and fetal circulating HGF concentrations were comparedbetween 55 pregnancies with AGA infants and 16 pregnancies withSGA infants at birth. HGF concentrations were measured frommaternal and cord venous blood samples using an enzyme-linkedimmunosorbent assay. Umbilical artery blood pH and oxidativepressure (PO₂) were also measured. Maternal circulating HGFconcentrations (0.60 ± 0.35 ng/ml) in pregnancies withSGA infants were significantly lower than those (0.91 ±0.44 ng/ml) in pregnancies with AGA infants (P = 0.012). Therewere no significant differences in fetal circulating HGF concentrationsbetween both groups. No significant differences in umbilicalartery blood pH and PO₂ were found between both groups. Theseresults suggest that the maternal serum circulating HGF concentrationhas a significant role in fetal growth during pregnancy.     

促酰化蛋白水平与胎儿生长发育的关系研究

目的探讨脐血促酰化蛋白（ASP）水平与胎儿生长发育的关系。方法研究对象为大于胎龄儿（LGA）、适于胎龄儿（AGA）和小于胎龄儿（SGA）各30例。应用ELISA法测定血清和羊水ASP浓度、血清脂联素浓度,RIA法测定血清胰岛素和瘦素水平,用免疫比浊法测定血脂水平;并分析脐血ASP水平与母血和羊水ASP水平、胎盘重量、新生儿身长、性别、体质量、BMI、腰围、腰臀比、血脂、胰岛素、瘦素和脂联素水平,孕妇的体质量和BMI、血脂水平的相关性。结果①LGA的脐血ASP水平高于AGA,AGA的脐血ASP水平高于SGA,差异有统计学意义（P〈0.001）;三组新生儿血脂水平差异无统计学意义（P〉0.05）。②脐血ASP水平与新生儿出生体质量、身长、BMI、腰围、腰臀比、胰岛素、瘦素、脐血甘油三酯水平呈显著正相关（P〈0.001）,与血脂联素水平呈显著负相关（P〈0.001）,与母血和羊水ASP水平、胎盘重量无相关性（P〉0.05）。③男、女婴脐血ASP、血脂各成分水平比较差异均无统计学意义（P〉0.05）。结论促酰化蛋白参与胎儿生长发育调节,脐血ASP水平可反映胎儿的生长发育状况。     

Significance of IgE level in amniotic fluid and cord blood for the prediction of allergy

Intrauterine sensitization has been reported in animal and clinical studies. One study suggests that the amniotic fluid (AF) IgE level might be useful in predicting infant allergy. We followed for 1 year 83 newborns on whom we had 78 samples of AF, 82 of cord serum (CS), and 83 of maternal serum (MS). All infants were delivered by C-section at term. Amniotic fluid samples were aspirated through the exposed myometrium. Sanguineous specimens were excluded. Amniotic fluid, CS, and MS were tested for total IgE level and IgE RAST to three foods: cow's milk, egg white, and peanut. Data on family medical history, feeding history, and allergy symptoms were collected for 12 months. By 1 year 23% had probable allergy: recurrent wheezing = 8, food related G.I. symptoms = 7, and atopic dermatitis = 4. Allergy in formula-fed infants occurred more often than in those breast-fed for greater than 6 months. IgE in AF was greater than or equal to 0.5 IU/mL in 21/78 (27%); range = 0.5 to 5.9 and geometric mean = 0.76. No correlation was noted between AF total IgE and the appearance of allergy. RAST was equivocally positive in 1.2% AF. Cord serum total IgE was greater than or equal to 0.5 IU/mL in 6/82 (7%); range = 0.5 to 2.6 and geometric mean = 0.72. Allergy appeared in 67% of infants with CS total IgE greater than or equal to 0.5 IU/mL. RAST was negative in all CS samples. In this limited series, AF IgE did not seem to have predictive value of allergy in infancy.     

The role of amniotic fluid interleukin-6, and cell adhesion molecules, intercellular adhesion molecule-1 and leukocyte adhesion molecule-1, in intra-amniotic infection

PROBLEM: To determine amniotic fluid concentrations and correlations of interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), and leukocyte adhesion molecule-1 (LAM-1) in patients with and without intra-amniotic infection. METHOD OF STUDY: Fourteen specimens with intra-amniotic infection and 45 without intra-amniotic infection were studied. Intra-amniotic infection was defined as the presence of a positive amniotic fluid culture. Amniotic fluid IL-6, ICAM-1, and LAM-1 levels were determined by an enzyme-linked immunoassay, and normalized by amniotic fluid creatinine levels. RESULTS: Amniotic fluid concentrations of IL-6 and LAM-1 were significantly higher in patients with than without intra-amniotic infection. However, amniotic fluid ICAM-1 concentrations were not significantly different between two groups. Amniotic fluid IL-6, LAM-1, and ICAM-1 were positively correlated. CONCLUSIONS: Our data indicate that amniotic fluid IL-6 is significantly associated with an increased adhesion molecule expression in intra-amniotic infection. However, LAM-1 plays a more important role than ICAM-1 in intra-amniotic infection.     

Cytokine levels in midtrimester amniotic fluid in normal pregnancy and in the prediction of pre-eclampsia

Midtrimester amniotic fluid cytokines may reflect the function of the maternal immune system in the maternal-fetal interface and thus be predictive of pre-eclampsia. We determined the concentrations of interleukin (IL)-6, IL-8, IL-10, IL-11, IL-12, IL-15, tumour necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta in amniotic fluid at 14-16 weeks of gestation from women with normal pregnancies and from those who subsequently developed severe pre-eclampsia. The concentrations of the cytokines in amniotic fluid did not significantly differ between patients and normal controls. The median concentration of IL-6 was 950 pg/ml in normal pregnant women and 578 pg/ml in the patient group. The median concentration of IL-8 was 606 pg/ml in normal controls and 294 pg/ml in the patient group. The levels of IL-6, IL-8 and TGF-beta correlated positively with each other. TNF-alpha concentrations were low and similar in both groups. IL-10 and IL-12 were detected at very low levels in 37 and 7% of the samples, respectively. No difference was found in IL-15 concentrations between the groups. IL-11 was found only at low levels in both groups. Although none of the cytokines measured was predictive of pre-eclampsia, this study provides information of cytokines in amniotic fluid during the period when the spiral arteries are remodelled.     

Cytokines of the Human Reproductive Tract

PROBLEM: How is it possible that the female genital tract immunologically does not reject spermatooa nor the preimplantation and nidating embryo? METHODS: Four fluids of the human reproductive tract, i.e., human oviductal fluid (hOF), follicular fluid (FF), amniotic fluid (AF), and seminal plasma (SP) were investigated by specific ELISA for 18 cytokines. The concentrations, presence or absence of these compounds were evaluated for their possible role in the immunology of the reproductive process. RESULTS: Stem cell factor and IL-11 were detected in all reproductive tract fluids examined whereas large amounts of IL-1β and IL-1RA was found in AF and hOF. Follicular fluid revealed IL-2. HOF contained IL 2, IL-6, IL-8, TNF-α, MIP-1α, IFN-γ, and high levels of IL-1β, IL-10, IL-1RA, and sIL-2R. Amniotic fluid contained sIL-2R, IL-8, IL-1β, IL-1RA, IL-6, TNF-α, and MIP-1α. No IL-12 or IL-13 was detected in hOF, follicular fluid, or amniotic fluid. Almost no free TGF-β₁ or TGF-β₂ was found in any reproductive tract fluid except seminal plasma. Seminal plasma contained large quantities of free TGF-β₁ (9,220 ± 3,635 pg/mL) in addition to large quantities of latent TGF-β₂ (2,933 ± 2,169 pg/mL) and TGF-β, (71,000 ± 3,240 pg/mL). Furthermore, considerable concentrations of IL-8 (1900 ± 374 pg/mL) and sIL-2R (350 μ/mL) exist in seminal plasma. CONCLUSIONS: HOF contains a high level of IL-10 (588 ± 304 pg/mL), a powerful immune suppressor which probably plays a role in regulating immune responses in the fallopian tube and possibly in the endometrial cavity. Our observations suggest that seminal plasma with its huge content of TGFβ provides immune protection for sperm. Unfortunately, such high concentrations of TGFβ may also inhibit an immune defense in any organ in which semen is deposited.     

羊水与自体血培养后刺激花生四烯酸代谢物的释放

目的：探讨人羊水在体外刺激自体血细胞释放前列环素（PGI₂）、血栓素A₂（TXA₂）和白三烯C₄（LTC₄）等花生四烯酸代谢物的作用。方法：取产妇羊水与自体血进行培养,用放射免疫分析法检测血中血栓素B₂（TXB₂）和6-酮前列腺素F_1α（6-Keto-PGF_1α）的含量,用酶联免疫法检测LTC₄。结果：羊水能刺激血细胞释放TXA₂和LTC₄,胎粪污染的羊水作用更为明显。TXB₂的含量由加羊水培养前的(63.5±52.0) ng/L增加到培养后的(189.1±102.0) ng/L（P<0.01）,用胎粪污染羊水与血培养后增加到(289.2±113.2) ng/L（P<0.01）;LTC₄的含量由培养前的(40.1±39.7) ng/L增加到培养后的(293.5±206.1) ng/L（P<0.01）,胎粪污染组增加到(387.2±214.6)ng/L（P<0.01）,但前列环素仅有轻度增加,无显著性差异(P>0.05)。结论：羊水能刺激血细胞释放花生四烯酸类生物活性物质,使其正常的平衡状态被破坏,可能与羊水栓塞的发生机理有关。     

Hypergonadotrophinaemia with reduced uterine and ovarian size in women born small-for-gestational-age

BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size.     

Amniotic fluid has higher relative levels of lentivirus-specific antibodies than plasma and can contain neutralizing antibodies.

BACKGROUND: The in utero transmission rate of HIV-1 is estimated to be 10-15% in the absence of interventions and breastfeeding. Natural protective mechanisms involving lentivirus-specific antibodies may therefore exist to limit in utero transmission of lentiviruses. OBJECTIVES: HIV-1- and SIV-specific immunoglobulin G (IgG) levels in amniotic fluid samples from humans and rhesus macaques were assessed. STUDY DESIGN: HIV-1- and SIV-specific immunoglobulin G levels, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were determined using a quantitative Western blotting procedure. Amniotic fluid from rhesus macaques was tested for the ability to neutralize SIV infection of CEMX174 cells. RESULTS: The levels of HIV-1- and SIV-specific immunoglobulin G, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were approximately 3-10-fold higher than in plasma. The ability of antibodies in human amniotic fluid samples to neutralize viral infectivity could not be assessed, because zidovidine was present in the samples. Most amniotic fluid samples from rhesus macques not treated with antiretrovirals were able to neutralize SIV infectivity, except for a sample from a SIV positive rhesus whose infant was infected in utero. CONCLUSIONS: Active immunity to HIV-1 resulting in virus-specific antibodies in amniotic fluid exists, and may be a natural barrier to in utero infection. This may provide hope for stimulating neutralizing antibody via vaccine design.     

Size for Gestational Age and Neonatal Temperament in Full-Term and Preterm AGA-SGA Twin Pairs

Temperament was compared during the neonatal period betweenappropriate-for-gestational-age (AGA) and small-for-gestational-age(SGA) infants from 29 pairs of full-term and 15 pairs of pretermsame-sex twins. The evaluation of neonatal temperament includedratings of irritability, resistance to soothing, activity level,reactivity, and reinforcement value. The results of analysesof variance of paired comparisons indicated that, in the main,for both the full-term and preterm groups, there were no significantdifferences between AGA and SGA infants in the behavioral areas.The exception to this generalization was the finding that full-termSGA infants were less irritable than full-term AGA infants.Overall it was concluded that being small for gestational agedoes not place the infant at risk for deviance in behaviorsrelated to temperament during the neonatal period.     

Birth weight in pre-eclamptic and normotensive twin pregnancies: an analysis of discordance and growth restriction

The aim of this study was to verify whether twin pregnancies complicated by pre-eclampsia were associated with a higher rate of inter-twin weight discordance or an increased prevalence of small for gestational age (SGA) neonates than in normotensive twin pregnancies. A 17 year retrospective study was undertaken by examining 76 twin pregnancies complicated by pre-eclampsia and comparing them with 400 normotensive twin pregnancies. The case notes were reviewed in reference to birth weight differences, birth order, pregnancy outcome and inter-twin birth weight discordance. Statistical analyses were performed with t-test, contingency tables, regression curves, rank sum test and non-parametric survival plots. Power analysis was also carried out. Pre-eclamptic twin pregnancies were delivered at similar weeks of gestation to normotensive. They resulted in a smaller size for the second twin the earlier the delivery week, while in normotensive twin pregnancies no significant difference occurred at any week. Twin pregnancies complicated by pre-eclampsia showed higher rates of SGA neonates among second twins than those with normal pressure. The >25% discordance was associated with lower gestational age at delivery in each group [mean (range) 33 weeks (27-38) versus 37 (29-41), P < 0.005 pre-eclampsia and 35 weeks (25-41) versus 38 (25-42), P < 0.001 normotensive]. In pre-eclampsia the concomitant occurrence of SGA second twin and the discordance >25% was associated with shorter gestation while the presence of SGA second twin alone was not.     

Amniotic fluid alphafetoprotein measurements in the early prenatal diagnosis of central nervous system disorders

Amniotic fluid alphafetoprotein (AFP) has been measured in 520 pregnancies between 8 and 24 weeks of gestation. The normal range of values has been defined for fortnightly periods between these limits. Grossly elevated AFP concentrations were found in four pregnancies leading to spina bifida and nine pregnancies leading to anencephaly. Slightly elevated AFP concentrations were found in one twin pregnancy and two pregnancies affected by rhesus isoimmunisation. Normal AFP values were observed in 36 amniotic fluids from pregnancies where the outcome was rhesus isoimmunisation, an inborn error of metabolism, a cytogenetic disorder or a birth defect unrelated to the central nervous system. The reliability of amniotic fluid AFP in the early prenatal diagnosis of spina bifida and anencephaly and the possibility of performing assays on samples sent by post from any part of the world are emphasized.