Clinical use of placental hormones in pregnancy management.

Across human pregnancy, placenta represents a transit of oxygen and nutrients from the mother to the fetus and actively produces a large number of hormones that serve to regulate and balance maternal and fetal physiology. An abnormal secretion of placental hormones may be part of the pathogenesis of the main obstetric syndrome, from early to late pregnancy, in particular chromosomopathies, miscarriage, gestational trophoblastic diseases, preeclampsia, gestational diabetes, and pre-term delivery. The possibility to measure placental hormones represents an important tool not only for the diagnosis and management of gestational disorders, but it is also fundamental in the early identification of women at risk for these pregnancy complications. In the last decades, the use of ultrasound examination has provided additional biophysical markers, improving the early diagnosis of gestational diseases. In conclusion, while few placental hormones have sufficient sensitivity for clinical application, there are promising new biochemical and biophysical markers that, if used in combination, may provide a valid screening tool.

Human growth hormone and placental lactogen: structural similarity.

Sequential analysis of the first 17 amino acids from the amino-terminus of human placental lactogen reveals similarity to the sequence of human growth hormone, 11 of the residues being identical.

The effect of gestational age and labor on placental growth hormone in amniotic fluid.

OBJECTIVE: Placental growth hormone (PGH) is produced by trophoblast. This hormone becomes detectable in maternal serum during the first trimester of pregnancy. Its concentration increases as term approaches and becomes undetectable within one hour of delivery. PGH has important biological properties, including somatogenic (growth promotion), lactogenic, and lipolytic activity. Recently, PGH has been detected in amniotic fluid (AF) of midtrimester pregnancies. The purpose of this study was to determine whether PGH concentrations in AF change with advancing gestational age and in labor at term. DESIGN: AF was assayed for PGH concentrations in samples obtained from patients undergoing genetic amniocentesis between 14 and 18 weeks of gestation (n=67), normal patients at term not in labor (n=24), and pregnant women at term in labor (n=51). PGH concentrations were determined by ELISA. Non-parametric statistics were used for analysis. RESULTS: (1) PGH was detected in all AF samples; (2) patients in the midtrimester had a higher median concentration of PGH in AF than those at term (midtrimester: median: 3140.5 pg/ml; range: 1124.2-13886.5 vs. term: median: 2021.1pg/ml; range: 181.6-8640.8; p<0.01); (3) there was no difference in the median concentration of PGH between women at term, not in labor, and those in labor (term not in labor: median: 2113.4pg/ml; range: 449.3-8640.8 vs. term in labor: median: 2004.1pg/ml; range: 181.6-8531.5; p=0.73). CONCLUSIONS: (1) PGH is detectable in AF at both mid- and third trimesters; (2) the median AF concentration of PGH is significantly lower at term when compared to the second trimester; (3) labor at term is not associated with changes in the AF concentration of PGH. The role of this unique placental hormone now found in the fetal compartment requires further investigation.

Human placentophagy: Effects of dehydration and steaming on hormones, metals and bacteria in placental tissue.

INTRODUCTION: Human maternal placentophagy, the behavior of ingesting the own raw or processed placenta postpartum, is a growing trend by women of western societies. This study aims to identify the impact of dehydration and steaming on hormone and trace element concentration as well as microbial contamination of placental tissue. METHODS: A total of nine placentas have been processed: six were studied for hormone and trace element concentrations; eight were studied for microbial contamination. The concentrations of CRH, hPL, oxytocin and ACTH in samples of raw, steamed dehydrated and raw dehydrated placental tissue were detected using ELISA. A yeast bioassay was performed in order to detect estrogen equivalent (EEQ) and gestagen equivalent (PEQ) active substances. Elements (As, Cd, Fe, Pb, Se, Hg) were analyzed using ICP-MS. Isolated colonies from tissue and placenta swab samples were identified using Vitek MS. RESULTS: Following mean hormone concentrations were detected in raw placental tissue: CRH (177.88 ng/g), hPL (17.99 mg/g), oxytocin (85.10 pg/g), ACTH (2.07 ng/g), estrogen equivalent active substances (46.95 ng/g) and gestagen equivalent active substances (2.12 µg/g). All hormones were sensitive to processing with a significant concentration reduction through steaming and dehydration. Microorganisms mainly from the vaginal flora were detected on placenta swab samples and samples from raw, steamed, dehydrated and steamed dehydrated tissue and mostly disappeared after dehydration. According to regulations of the European Union the concentrations of potentially toxic elements (As, Cd, Hg, Pb) were below the toxicity threshold for foodstuffs. CONCLUSION: The commonly used protocols for preparation of placenta for its individual oral ingestion reduce hormone concentrations and bacterial contamination.

Human placental lactogen: studies of its acute metabolic effects and disposition in normal man.

The acute metabolic effects and disposition of human placental lactogen (HPL) have been studied in 15 men and 8 women during continuous intravenous infusions. The mean plasma half-life, metabolic pool size, and turnover rate of HPL are comparable to the values previously reported for human growth hormone (HGH). From the data presented, we calculate that the placenta secretes approximately 290 mg HPL daily at term. After 12-hour infusions of HPL in physiologic amounts, impairment of glucose tolerance despite increased plasma insulin responses to glucose was observed in 7 of 8 subjects tested. However, HPL, unlike HGH, did not produce significant changes in blood glucose, plasma insulin, or plasma free fatty acid concentrations in fasting subjects before glucose administration or in carbohydrate tolerance or plasma insulin responses to glucose during 5-hour infusions. These findings are compatible with the thesis that HPL is a physiologic antagonist to insulin during pregnancy.

Placental growth hormone is increased in the maternal and fetal serum of patients with preeclampsia.

OBJECTIVES: Placental growth hormone (PGH) is a pregnancy-specific protein produced by syncytiotrophoblast and extravillous cytotrophoblast. No other cells have been reported to synthesize PGH Maternal. PGH Serum concentration increases with advancing gestational age, while quickly decreasing after delivery of the placenta. The biological properties of PGH include somatogenic, lactogenic, and lipolytic functions. The purpose of this study was to determine whether the maternal serum concentrations of PGH change in women with preeclampsia (PE), women with PE who deliver a small for gestational age neonate (PE + SGA), and those with SGA alone. STUDY DESIGN: This cross-sectional study included maternal serum from normal pregnant women (n = 61), patients with severe PE (n = 48), PE + SGA (n = 30), and SGA alone (n = 41). Fetal cord blood from uncomplicated pregnancies (n = 16) and PE (n = 16) was also analyzed. PGH concentrations were measured by ELISA. Non-parametric statistics were used for analysis. RESULTS: (1) Women with severe PE had a median serum concentration of PGH higher than normal pregnant women (PE: median 23,076 pg/mL (3473-94 256) vs. normal pregnancy: median 12 157 pg/mL (2617-34 016); p < 0.05), pregnant women who delivered an SGA neonate (SGA: median 10 206 pg/mL (1816-34 705); p < 0.05), as well as pregnant patients with PE and SGA (PE + SGA: median 11 027 pg/mL (1232-61 702); p < 0.05). (2) No significant differences were observed in the median maternal serum concentration of PGH among pregnant women with PE and SGA, SGA alone, and normal pregnancy (p > 0.05). (3) Compared to those of the control group, the median umbilical serum concentration of PGH was significantly higher in newborns of preeclamptic women (PE: median 356.1 pg/mL (72.6-20 946), normal pregnancy: median 128.5 pg/mL (21.6-255.9); p < 0.01). (4) PGH was detected in all samples of cord blood. CONCLUSIONS: (1) PE is associated with higher median concentrations of PGH in both the maternal and fetal circulation compared to normal pregnancy. (2) Patients with PE + SGA had lower maternal serum concentrations of PGH than preeclamptic patients without SGA. (3) Contrary to previous findings, PGH was detectable in the fetal circulation. The observations reported herein are novel and suggest that PGH may play a role in the mechanisms of disease in preeclampsia and fetal growth restriction.

A new nonisotopic, highly sensitive assay for the measurement of human placental growth hormone: development and clinical implications.

Human placental GH (hGH-V) is a variant of pituitary hGH (hGH-N) synthesized and secreted by syncytiotrophoblasts during pregnancy. It differs from hGH-V by only 13 amino acid residues, which makes difficult a specific measurement of hGH-V without interference from hGH-N. To overcome the analytical difficulties, we produced new high affinity monoclonal antibodies specific for hGH-V. Precise screening and epitope mapping allowed identification of a pair of monoclonal antibodies suitable to establish a highly sensitive assay for hGH-V measurement. In a prospective, longitudinal study involving 84 normal pregnancies, we measured maternal concentrations of hGH-V, leptin, IGF-I, and cord blood IGF-I. hGH-V was detectable as early as gestational week (GW) 7. Mean concentrations of hGH-V increased from 0.9 +/- 0.5 microg/liter (GW 7-13) to 2.8 +/- 0.9 microg/liter (GW 18-22), 7.3 +/- 2.6 microg/liter (GW 28-32), and 13.0 +/- 9.6 (GW 37-41). A negative correlation was found between prepregnancy body mass index and hGH-V concentrations from GW 28 onward. Peak hGH-V levels occurred at wk 36.5 +/- 2.6 and were significantly lower in obese (P = 0.029) and higher in underweight (P = 0.035) mothers compared with those in mothers of normal weight. The increase in hGH-V between GW 18-22 and GW 28-32 was negatively correlated to the increase in maternal leptin during this period (P = 0.027). Maternal IGF-I concentrations were correlated to those of hGH-V from GW 18 onward (P = 0.039). The strongest correlation was found at GW 28-32 (P = 0.001). Furthermore, maternal hGH-V concentrations in late pregnancy correlated with cord blood IGF-I (P = 0.025) and size of the newborn (P = 0.017). These results, obtained by a new, highly sensitive hGH-V-specific immunoassay, highlight the importance of maternal hGH-V in the regulation of maternal and fetal IGF-I. In addition, the results indicate that maternal weight has a major impact on circulating concentrations of hGH-V.

Progress in fetal assessment.

The growth areas in fetal assessment in late pregnancy have been studied by making a quantitative review of the papers in four obstetric journals. Of the 130 relevant papers published, in 1973, the most common subject treated was the phospholipid test of fetal lung maturity. Other important tests reviewed were estrogen assays, ultrasonic studies, human placental lactogen and alpha-fetoprotein measurements. The clinical value of phospholipid tests was demonstrated; liquor creatinine assays are much inferior in assessing fetal maturity. Plasma estriol assays are likely to be of increasing importance in clinical practice. Some caution should be applied in the interpretation of ultrasonic measurements of biparietal diameter as a test of fetal development and well-being.

A possible functional necklace formed by placental antigen X-P2-immunoreactive and intensely acetylcholinesterase-reactive (PAX/IAE) glomerular complexes in the rat olfactory bulb.

The relationship between placental antigen X-P2 (PAX)-immunoreactive glomeruli and intensely acetylcholinesterase-reactive (IAE) patchy regions was evaluated by comparison of neighboring cryostat sections of the rat olfactory bulb. Both groups of distribution show similar necklace patterns. Each IAE region consists of heterologous glomerulus-like structures with variable acetylcholinesterase reactivity: strongly and less-reactive (IAE-S and IAE-L) structures. The PAX-immunoreactive glomeruli were detected as parts of the IAE-L portions. Three heterologous PAX/IAE glomeruli or glomerulus-like structures (IAE-S, IAE-L/PAX and IAE-L/non-PAX structures) locally form a distinct glomerular complex, the 'PAX/IAE glomerular complex'. At the caudal end of the main olfactory bulb, nine to sixteen such complexes occur at intervals and form a circumferential 'necklace'. Since one of them corresponds to the 'modified glomerular complex' involved in rat suckling behavior, the entire 'necklace' may be associated with processing olfactory stimuli eliciting or suppressing the suckling response.

Screening of an enterovirus specific RT-PCR ELISA method for the quantification of enterovirus genomes in human body fluids by means of a three-level experimental design.

In order to obtain a detection limit as low as possible for a quantitative enterovirus specific RT-PCR ELISA assay, optimal reaction conditions, which give rise to the highest response, need to be determined. This was done by investigating the influence of 13 factors, selected from RT and PCR, in a multivariate approach by means of a well-balanced three-level screening design, derived from a three-level Plackett--Burman design. Optimal reaction conditions could be determined by calculation and evaluation of the effects of the different factors on the response, i.e. the measured absorbance of the ELISA detection. The method will be used to study a possible longitudinal relationship between enteroviruses and the development of multiple sclerosis and juvenile diabetes.

Endocrine assessments of fetal-placental well-being.

Continued advances in perinatology and neonatology and the introduction of biochemical and biophysical methods for evaluating pregnancy have substantially improved the perinatal outcome. Biochemical evaluation of placental function appears to play an important role in the management of complications of early and late pregnancy. Improvements in methodology and increased experience in the application of the various techniques have enhanced our ability to diagnose normal and abnormal pregnancy. The various new placental proteins recently described have not yet found their place in modern obstetrics and thus far they do not seem to offer distinct advantage over more established methods for assessing fetoplacental function.

Update on pregnancy testing.

Laboratory testing is an extension of the physical examination, reaching sites that are otherwise inaccessible to the examiner. Pregnancy testing is one such diagnostic extension. Like physical examination, it must be used carefully. In choosing a pregnancy test for office use, many factors must be considered, so that accurate information will be available for patient management. Such factors as the technical skills and training of the office staff performing the test, shelf life of the test, need to refrigerate reagents, and frequency of usage are all important considerations. Test results must always be correlated with specific patients and clinical findings, and at times, doubts may be allayed by simply retesting patients with negative or equivocal results at a later time (currently a matter of days instead of weeks). Recent developments in pregnancy testing have been directed toward improved sensitivity and specificity, as well as speed, simplicity, and reduced cost. The clinical issue of greatest interest to most primary care physicians is the early diagnosis of normal pregnancy, where "early" may be defined as prior to the first missed menses. Diagnosis in the first 21 days of gestation is currently possible with more sensitive methods, and especially with enzyme-linked immunoassay. In this regard, because of its easy methodology and basic reliability, the enzyme-linked immunoassay may well become the new standard for office pregnancy testing.

PIP: Pregnancy tests aimed at detecting the presence of human chorionic gonadotropin (hCG) in maternal plasma and its excretion in urine have become a valuable diagnostic tool. The newer tests offer greater sensitivity and specificity than the older 2-minute slide tests or tube tests. At present, the most promising pregnancy tests are the enzyme-linked immunoassays. These are qualitative tests that involve enzyme-linked immunosorbent assay (ELISA) and monoclonal antibodies. This technology is readily adaptable to most clinic and office settings and may be run on either serum or urine specimens. Advantages include its ready availability, simplicity, sensitivity, and specificity for the beta subunit of hCG. Over-the-counter pregnancy tests for use by nonprofessionals have been available since the mid-1970s; however, these tests have a relatively high (25%) false-negative rate. Among the problems that have arisen in testing for pregnancy by hCG determination are the interference of proteinuria with urine pregnancy tests, an irreducible level of technical error, the tendency of certain drugs to produce a false-positive result, and quality control. In general, physicians should consider several factors--the technical skills and training of the office staff performing the tests, shelf life of the test, the need to refrigerate reagents, and frequency of usage--in selecting a pregnancy test for office use. Test results should be correlated with specific patients and clinical findings, and patients with negative or equivocal results should be retested a few days later.

[Tumor markers]. / Les marqueurs tumoraux.

Several substances, referred to as tumor markers, are associated with neoplasms development. The specificity of these cancer related substances or antigens depends on their nature (onco-fetal antigens, placental antigens) or on their concentration and physico-chemical forms (hormones, exocrine products, enzymes,...). On the basis of physico-chemical, immunochemical and biochemical analogies which exist between these tumor markers and substances normally found at particular times of life, a classification of these markers may be proposed. Tumor markers are almost constantly found within carcinoma cells by immunocytochemical techniques and are secreted by carcinoma explants in culture medium. On the hand, the release of tumor markers in biological fluids (blood, cerebrospinal fluid, urines,...) is less frequently detected by sensitive methods such as radioimmunoassay. Several factors are responsible for this discrepancy between the intra-tumoral presence of tumor markers and the lower incidence of their detection in biological fluids. These factors are discussed. These tumor markers have attracted considerable attention from pathologists and clinicians. Thus, detection of these substances, especially by immunocytochemical methods, may be related to a situation of neoplastic transformation and allow a functional classification superimposed to histological classification superimposed to histological classification of tumors. Moreover, ectopic production of hormones and/or neuromediators explains some clinical symptoms in cancer processes. Furthermore, products of normal cell activity at the origin of cancer (hormones, enzymes, exocrine products) when evidenced within the neoplastic cells or within serum might constitute a hormonal dependence index useful for therapeutical orientation. Finally, tumor marker levels are related to the local and systemic extension of the neoplasia and may be considered as valid index of prognosis. The determination of the levels of these tumor markers provides a quantitative criterion of the evolution of the neoplastic disorder and for following the efficacy or inefficacy of treatment.

Placental growth hormone, pituitary growth hormone, insulin-like growth factor, and ghrelin in umbilical cord blood serum and amniotic fluid.

INTRODUCTION: In the search for biomarkers that allow the prediction of neonatal growth and development, placental growth hormone(PGH), pituitary growth hormone (GH1), insulin-like growth factor 1 (IGF-1), and ghrelin concentrations were assessed in the amniotic fluid and in the umbilical cord blood of 92 neonates. MATERIAL AND METHODS: The proteins were assayed by the ELISA method. Their concentration values were compared in 57 full-term neonates and 35 prematurely born neonates, as well as in both large (> 4,000 g) and small neonates (< 2,500 g). Also, body mass and placenta mass were compared. RESULTS: Statistically significant differences both between prematurely born neonates and full-term neonates and between large and small neonates were obtained only in terms of the body mass of neonates and placenta mass. The concentration values of the hormones studied did not show statistically significant differences. A distinct tendency was noticed towards an increase in PGH concentration in both prematurely born and small neonates. In large neonates, statistically significantly higher IGF-1 concentrations were found compared to the prematurely born neonates. CONCLUSIONS: Our studies indicate an important role for PGH in maintaining a proper IGF-1 pool and demonstrate the existence of a direct influence on the function of the placenta in prematurely born neonates through the activation of compensation mechanisms,which stimulate IGF-1 synthesis.