Daily immunoactive and bioactive human chorionic gonadotropin profiles in periimplantation urine samples.
ABSTRACT A need exists for broadly applicable biomarkers of pregnancy outcome in population-based studies that assess environmental hazards to human reproduction. Previous studies have demonstrated that during the periimplantation period, measures of the circulating levels of immunoreactive hCG (IhCG) are not predictive of pregnancy outcome, whereas measurements of the circulating levels of bioactive hCG (BhCG) provide information relating to pregnancy outcome and might provide the basis for an early biomarker of pregnancy outcome. However, for this biomarker to have broad application in population-based studies, it must be adapted to urinary hCG metabolites. The principle objective of the present study was to characterize the periimplantation excretion patterns of urinary hCG metabolites of pregnancies that resulted in live birth (LB), early pregnancy loss (EPL), and recognized clinical abortion (CAB) with an immunoenzymometric assay specific to intact hCG and an LH/chorionic gonadotropin cellular bioassay as the basis for a preliminary comparison between successful (LB) and failing (EPL and CAB) outcome groups. Automated immunoassays for FSH and hCG were used to define each conceptive cycle's implantation window. The timing of first hCG detection was significantly later for the EPL group. Pregnancies that resulted in LB had consistently rising average daily IhCG and BhCG levels, with no significant differences when average daily IhCG and BhCG measurements were compared (Student t-test, P>0.05), whereas pregnancies that resulted in CAB and EFL had lower average daily IhCG and BhCG levels that increased inconsistently. These findings demonstrate that critical information related to pregnancy outcome may be present when multiple urinary hCG isoforms are measured. Further data suggest that the rate of change for the ratio of daily BhCG over IhCG levels might be useful as the basis of a broadly applicable early biomarker for pregnancy outcome.
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ABSTRACT: To characterize the hourly profiles of hCG secretion in blood during conceptive cycles that ended in successful pregnancy. Prospective study. University fertility clinic and research laboratories. Healthy spontaneously ovulating women with regular menses, no history of infertility, and either no male partner or an azospermic partner. Frequent blood samples were collected daily from 11 spontaneously ovulating women during 11 cycles of artifical insemination with donor semen. The concentrations of hCG, LH, and FSH were measured in the blood by immunoassay. The concentration of hCG in the frequent blood samples and the rate that the concentration of hCG changed during the period of frequent sampling. For the conceptive cycles resulting in successful pregnancies analyzed, hourly hCG concentrations were observed to increase in a consistent nonpulsatile manner. These data provide the first characterization of the hourly secretion profile of hCG in early pregnancy as well as provide further evidence that individual daily blood samples are sufficient for the accurate assessment of pregnancy.Fertility and sterility 07/2007; 87(6):1413-8. · 4.30 Impact Factor
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ABSTRACT: To define the variability of menstrual cycle length and contribution of follicular and luteal phases to overall cycle variability, and to examine the rise in urinary hCG in early pregnancy. Menstrual cycle study. Urine samples from 101 women (recruited from two south-east counties in the UK) were assayed to determine day of luteinising hormone (LH) surge, lengths of follicular and luteal phases and correlations with total menstrual cycle length. HCG study. Daily urine samples collected from 86 women prior to conception until 43 days post-conception were assayed for hCG and examined versus time since LH surge, determined using fertility test kits. Mean menstrual cycle length was 27.7 +/- 3.4 days, mean follicular phase length was 14.5 +/- 3.4 days and mean luteal phase length was 13.2 +/- 1.9 days. Total cycle lengths varied between and within women. There was a significant correlation (r(2) = 0.70) between follicular phase length and total cycle length; luteal phase length was less variable and showed no association with total cycle length. Concentrations of hCG were significantly similar between women when referenced against the day since LH surge. Three thresholds were determined to indicate time since conception as 1-2 weeks, 2-3 weeks and 3+ weeks. Total cycle length variation is mainly determined by follicular phase variation and predicting menses onset to estimate time of pregnancy testing is unreliable. Evaluating concentrations of hCG relative to LH surge results in consistent increases between women up to 21 days after conception. Therefore, urinary hCG concentration can be used to accurately estimate time since conception.Current Medical Research and Opinion 03/2009; 25(3):741-8. · 2.37 Impact Factor
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ABSTRACT: STUDY QUESTION: Are secreted extracellular matrix (ECM) remodelling elements, relevant to embryo implantation and placentation, modified by hCG in endometrial stromal cells (ESCs)? SUMMARY ANSWER: hCG decreases tissue inhibitor of metalloproteinase 1 (TIMP-1) secretion in ESCs, thereby facilitating extravillous trophoblast invasion in vitro. WHAT IS KNOWN ALREADY: Successful embryo implantation and placentation depend on the appropriate invasion of the trophoblast into the maternal endometrial stroma. hCG is one of the earliest embryo-derived secreted signals in the endometrium which abundantly expresses hCG receptors. However, there is little data concerning the effects of hCG on endometrial ECM remodelling with respect to embryo implantation. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study was conducted in an academic research laboratory within a tertiary-care hospital. Samples were collected from 36 women undergoing benign gynaecological surgery during the mid-secretory phase. ESCs were isolated and stimulated with hCG (10 UI/ml) or vehicle. Conditioned media (CM) were analysed to determine changes in the secreted profile of nine matrix metalloproteinases (MMPs) and three tissue-specific inhibitors of MMPs (TIMPs) using an ELISA array. Data were confirmed by gelatine zymography, western blot and ELISA. The HTR8/SVneo cell line served as a model for trophoblast cells. The invasive potential of trophoblast cells was assessed using Transwell invasion assays under CM or co-culture conditions with ECS and the role of regulated molecules was examined by using immunoprecipitation in CM prior to the assessment of invasive potential. MAIN RESULTS AND THE ROLE OF CHANCE: MMP-2 levels increased 30%, whereas TIMP-1 levels decreased 20% in CM from ESCs stimulated with hCG (P < 0.05). Gelatine zymography confirmed an increase in MMP-2 activity (P < 0.05). ELISA and western blotting also confirmed the reduction in TIMP-1 upon hCG treatment (P < 0.05). Invasion assays revealed a ∼50% increase in invading HTR8/SVneo cells in chambers with hCG-stimulated ESCs compared with the control (P < 0.05). Immunodepletion of TIMP-1 from control ESC-CM partially resembled the effect of CM from hCG-stimulated ESCs in the trophoblast invasion assays. LIMITATIONS, REASONS FOR CAUTION: The assays were performed in vitro and ESCs were not decidualized, therefore they reflected the very early stages of embryo implantation or the advanced stages when decidualization fails. WIDER IMPLICATIONS OF THE FINDINGS: Our data suggest that hCG induces endometrial stromal extracellular remodelling by modulating secreted MMP-2 and TIMP-1. This regulation may be physiologically relevant because it increases the invasive potential of trophoblast-derived cells. At present, few data exist concerning the implications of hCG and endometrial ECM remodelling in embryo implantation. Hence, our results should be confirmed by further in vivo studies. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by FONDECYT 11100443, PBCT-PSD51 (IDIMI) and FONDAP 15010006. None of the authors have any conflicts of interest to declare.Human Reproduction 05/2013; · 4.59 Impact Factor