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Daily measurements of human chorionic gonadotropin (HCG) beta subunit, luteinizing hormone (LH), and progesterone were carried out in 24 subjects wearing intrauterine contraceptive devices. Detectable HCG was not found in any subject, but in four subjects delayed LH pulses resulted in apparent low levels of HCG because of cross-reactivity in the HCG beta subunit radioimmunoassay.
Plasma chorionic gonadotropin levels were measured by three different assay methods during early pregnancy in four patients following induction of ovulation with Pergonal and hCG. Radioligand-receptor assay of unextracted samples was subject to non-specific interference by plasma proteins, causing an apparent elevation of gonadotropin levels during the first few days after fertilization. By contrast, the gonadotropin values measured by a highly sensitive LH/hCG bioassay were consistent with those obtained with a sensitive and specific radioimmunoassay for hCG, and showed that the first significant rise in plasma hCG occurred 9 to 13 days after ovulation. These results indicate that hCG does not appear in the maternal circulation until after the initiation of implantation of the blastocyst.
In a cross-sectional study, the serum levels of pregnancy-specific beta 1-glycoprotein (PSBG), hCG, human LH, and progesterone were measured by RIAs during 94 mid or late luteal phases of 69 women using oral contraceptives. Subsequent spontaneous menstruation took place in every cycle. None of the women using oral contraceptives had any PSBG or hCG-like immunoreactivity in serum. In women with intrauterine devices, PSBG was found in six cycles (6.4%) and hCG-like immunoreactivity was demonstrated in one cycle only, where PSBG also was present. In two out of six PSBG-positive cycles, menstruation was delayed by 5 and 16 days. Although rare, the transient occurrence of trophoblastic antigens in women using intrauterine contraception is taken as evidence for an occult pregnancy in these apparently infertile cycles.
The relation of the hypothalamic-pituitary effect on gonadotrophin secretion and the concentration of serum hCG after molar abortion was investigated. Gonadotrophin release after a bolus injection of LH-RH or conjugated oestrogens was observed in 17 women until 5 months after molar abortion. Little if any response of gonadotrophin was observed at a hCG level of 100 mIU/ml or more, but the response of LH and FSH to LH-RH were restored to normal when the serum hCG level decreased to below 100 mIU/ml. A normal response of LH to conjugated oestrogens was observed at a serum hCG level of 20 mIU/ml or less. These findings suggest that a high level of hCG interferes with pituitary gonadotrophin secretion, that the threshold hCG levels for normal responses of gonadotrophins to LH-RH and oestrogen are 100 and 20 mIU/ml, respectively, and that secretion of gonadotrophins is restored even in the presence of a low hCG level.
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Thirty-six pregnant women and 15 normally menstruating women were each given 100 microng of synthetic luteinizing hormone releasing hormone (LHRH) by a single intravenous injection. Human chorionic gonadotropin (hCG), luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels were determined by specific radioimmunoassay (RIA) technics. For the determination of the serum LH levels, the LHbeta-RIA method, which is unaffected by hCG at sample levels as high as 500 IU/ml, was used. Serum concentrations of LH and FSH were lower in pregnant women than in the normal women in the follicular and luteal phases. While the release of LH was observed in pregnant women following the administration of LHRH, the average net increase was less than that seen in both the follicular and luteal phases. During pregnancy, there was a progressive decrease in the LH response to LHRH, but no release of FSH.
Three patients with choriocarcinoma had clinical and biochemical evidence of hyperthyroidism. Diminution in the thyrotoxicosis closely paralleled the fall in human chorionic gonadotrophin (hCG) levels. Three patients originally presented to internal medicine units as a problem of hemoptysis. Thyroid-stimulating hormone bioassay activity was demonstrated in the serum of all three patients prior to therapy. Recently evidence has been presented that hCG has intrinsic thyrotropic activity and that in conditions, such as hydatidiform mole, in which serum hCG levels are grossly elevated this thyrotropic activity can be sufficient to produce hyperthyroidism. Two of our cases supported the concept that hCG was also the substance with thyroid-stimulating activity in patients with choriocarcinoma. The third case left open the possibility that, in addition to the thyroid-stimulating activity of hCG, there may also be the production of a true ectopic thyroid-stimulating hormone (TSH). It is considered that the development of biochemical and clinical thyrotoxicosis in patients with choriocarcinoma depends upon the duration of the choriocarcinoma and the level of hCG.
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The abortifacient effect of a single-dose, long-acting vaginal suppository containing 3.0 mg of 15-methyl PGF2 alpha methyl ester was investigated in 104 early pregnancies. The pregnancy was terminated in 91 per cent of the cases. The abortion was uncomplicated in 79 patients, while 12 patients experienced prolonged bleeding. In 21 uncomplicated cases, VabraR curettage done 4 weeks after therapy revealed necrotic residual tissue in 16 patients and nonspecific endometritis in 20 patients. Residual tissue was found in about 50 per cent of the patients curettaged after 1st menstruation, but no residua was found after 2nd menstruation. In patients with prolonged bleeding, substantial amounts of necrotic residual tissue was found in all patients curettaged 4 weeks after therapy. The decline of serum hCg and plasma progesterone levels was significantly slower in these patients as compared with uneventful abortions.
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A simple, sensitive, and reproducible method for the detection of urinary human chorionic gonadotropin (hCG) and diagnosis of early human pregnancy is reported. A 5-ml aliquot of filtered early-morning urine sample was concentrated in a microconcentrator (M) to 0.1 ml of retentate which was diluted with 0.4 ml of distilled water and tested in a hemagglutination inhibition test (M-HIT). Also, a 0.1-ml aliquot of filtered unconcentrated urine sample was diluted with 0.4 ml of distilled water and tested in the same hemagglutination inhibition test (HIT). Urine samples from women of reproductive age; from perimenopausal, menopausal, and proteinuric women; and from adult males were tested in the HIT and M-HIT. Some of these urine samples were also tested in the mouse ovulation bioassay (MOB). The M-HIT was significantly more reliable than the HIT for diagnosis of early pregnancy 25 to 55 days after menses. Correct negative results with the M-HIT were obtained in urine samples of most of the nonpregnant cycling, perimenopausal, and menopausal women, and adult males. Urine samples from subjects with severe proteinuria gave false-positive types of reactions in the M-HIT. Positive results were obtained in the MOB with a number of urine samples from pregnant, perimenopausal, and menopausal women. A properly conducted M-HIT should be very valuable in diagnosing pregnancy as early as the 26th day of the cycle in regularly menstruating women.
The usefulness of The Nonhuman Primate Pregnancy Test kit for diagnosis of pregnancy in chimpanzees was determined. This hemagglutination inhibition test for urinary chorionic gonadotropin accurately indicated conception by positive responses in 151 to 153 specimens collected between 20 and 133 days after the estimated day of fertilization. The rate of false positive responses did not exceed 1%.
Human chorionic tissues were cultivated in vitro in they presence of 3H-proline in order to study the synthesis of the hCG and its subunits by the placenta. After terminating the culture, tissue extracts and media were individually gel-filtrated on Sephadex G-100. The eluted fractions were radioimmunoassayed for hCG, hCGalpha and hCGbeta and were measured for 3H-radioactivity. Label incorporation was determined by immunoprecipitation. Elution profiles of tissue extracts showed the existence of large immunologic forms of hHCG, hCGalpha and hCGbeta emerging near the void volume. The amounts of these large immunologic species in chorionic tissue gradually decreased during the course of cultivation. 3H-proline was almost exclusively incorporated into the large immunologic forms of hCG, hCGalpha and hCGbeta within the chrionic tissue during the 5-hour exposure. A great quantity of hCGalpha was found in the media after the 3-day culture, while the amount of hCGbeta found in the media was minute. After a 15-minute pulse, the 3H-radioactivity peak within the chorionic tissue appeared in the void volume, conicidental with hCG immunoreactivity. During the chase period, there was shift of the 3H-radioactivity peak associated with hCG immunoreactivity from the void volume to the more retarded area. In the media until after the 60-minute chase, no labeled hCG and its subunits appeared. Within the media after 3-hour chase, no labeled hCG peak associated with 3H-radioactivity was more retarded on Sephadex G-100 than that within the tissue extract after the 15-MINUTE pulse. These results suggest that the large immunologic forms of hCG, HCGalpha and hCGbeta are synthesized as the earliest detectable biosynthetic forms and that the may then be converted to small molecule species. In the culture of molar trophoblastic tissues after a 15-minute pulse, considerable amounts of hCG and its subunits accompanied by high 3H-radioactively had already been secreted into the media. These observations suggest that protein synthesis by molar trophoblastic tissue is markedly enhanced as compared with that by normal chorionic tissue and that immunoreactive materials synthesized in molar trophoblastic tissue may be secreted more radily than those synthesized a in normal chorionic tssue.
Determination of human chorionic gonadotropin (HCG) values in the serum by the radioimmunoassay technique, was performed in 23 women with suspected ectopic pregnancies. In 16 cases the values of HCG were high and the diagnosis of ectopic pregnancy was verified by laparoscopy and laparotomy. In 7 cases low HCG values were found and ectopic pregnancy was excluded. The detection of HCG in the serum was found to be an excellent tool for the early diagnosis of ectopic pregnancy, thus helping to prevent the dangerous sequelae which follow the late diagnosis of this condition.
A commercially prepared radioreceptor assay (RRA) for human chorionic gonadotropin (hCG) has been evaluated as a pregnancy test and in a quantitative assay to follow patients with hydatidiform mole. The RRA demonstrated almost 100% agreement in comparison with radioimmunoassay (RIA) and urinary hCG tests. In the quantitative assay, a limiting reliable concentration of 70 mIU/ml of hCG in serum could be obtained. Extremely good correlation was achieved between the RRA and RIA test for hCG in 2 patients with hydatidiform mole over a span of 3 months of followup after evacuation of the mole. The usefulness of the RRA as a replacement of RIA tests for hCG is discussed.
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Unconjugated oestrone (Oe1), oestradiol-17beta (Oe2), oestriol (Oe3), progesterone (P) and HPL in plasma were determined by radioimmunoassay and the immunological pregnancy-test in urine was carried out in 70 patients with normal pregnancy or imminent abortion from 4th-20th week of gestation. Oe2 and HPL showed the most pronounced rises, Oe3 increased especially after the first trimester. In cases with abortion symptoms and poor prognosis Oe2 and HPL gave the most reliable results concerning the endocrin function of early normal pregnancy. Oe1- and P-values in normal pregnancy did not differ so clearly from concentrations observed during normal menstrual cycles and were thus of less value. The pregnancy-test was positive (greater than 1000 IU/1) even in most cases of dead pregnancy and therefore not reliable. With increasing production of oestrogen precursors in the fetal adrenal cortex after the first trimester determination of Oe3 becomes more important. In cases with abortion symptoms in early pregnancy and subsequent normal development, plasma Oe2- and Oe3- values represented best criteria for a prognosis. -- For the diagnosis and control of the endangered early pregnancy we recommend, as a consequence of this study, determination of Oe2 up to the 13th week of pregnancy and thereafter Oe3 in maternal plasma.
Investigations on the influence of the diuresis effect upon the results of quantitative oestrogen and HCG determinations revealed that the oestrogen values increase with the 24-hour amount of urine. Oliguria and polyuria affect oestrogen excretion to a considerable extent; they have to be taken into account in prenatal diagnosis of pregnancy. Comparative HCG checks show that HCG concentration also varies considerable depending on fluid excretion. Diagnostic errors can be diminished or avoided when the quantitative HCG assessment is made on the 24-hour urine and then referred to the whole amount of urine.