Human chorionic gonadotropin regression following removal of ectopic pregnancy

Plasmatic Human Chorionic Gonadotropin (hCG) was studied in 41 patients undergoing salpingectomy for tubal pregnancy. On the temporal scale of our research, a biexponential model proved to be adequate to describe hCG clearance; the combined reading of the results of this research and those of other Authors have led us to maintain that hCG clearance is characterised by at least three components. HCG clearance was faster in patients with a higher initial hCG. Nevertheless the problem of hCG clearance depending on its initial value remains unsolved and requires further investigation. The regression curve and relative hCG values obtained in this study can be used as reliable models of comparison in the monitoring of patients undergoing conservative surgical treatment of tubal pregnancy.     

Human chorionic gonadotropin patterns after a single dose of methotrexate for ectopic pregnancy

Objective: The great variability in human chorionic gonadotropin (HCG) levels after a single dose of methotrexate (MTX) for ectopic pregnancy makes it difficult to predict treatment failure. We describe different patterns of HCG levels. Study design: Fifty patients were injected i.m. with 50 mg/m² of MTX for an ectopic pregnancy. Venous blood samples for HCG detection were obtained on the day of treatment (day 0), day 3 and day 7 and weekly until values were undetectable. Patients were classified as: group 1, persistent pathology (n=11); group 2, complete resolution with a decrease of HCG levels at day 3 (n=30); group 3, complete resolution after a rise of HCG values at day 3 (n=9). Statistical analysis was performed using the Mann–Whitney non-parametric test with 95% confidence intervals. Results: Values of day 0 were similar for all the groups. HCG levels of group 3 decreased rapidly after day 3 and at day 7 they were significantly different from levels of group 1. Differences in HCG levels between groups 2 and 3 became indistinguishable from day 21. Conclusion: The observation of patients undergoing resolution after an initial increase of HCG levels justify an expectant management for 1 week in clinically stable patients. The strategy to separate HCG curves in patients undergoing resolution may shed light on the different clinical responses to therapy for ectopic pregnancies. However, the phenomenon of the immediate rise of HCG should be better investigated.     

Human chorionic gonadotropin in the ectopic gestation

The ectopic pregnancy is a relatively common condition in the south African black patients. The beta-specific subunit radioimmunoassay for human chorionic gonadotrophin (HCG) was utilized in procuring information in our series of 30 patients. Levels of the hormone were significantly lower when compared to normal gestation of similar duration, never exceeding 2000 mIU/ml. The clearance rate of HCG following normal vaginal delivery was about 24 h and less variable than that of ectopic gestation. The half-life clearance rate of HCG in the ectopics could be divided into three phases, suggestive of HCG compartmentalization. The possible buffering effect of this hormone in the maintenance of the receptor-saturated pregnancy is discussed. The possibility that the HCG produced by the normal pregnancy is dissimilar to that of ectopic is speculated upon.     

Human chorionic gonadotropin alpha-subunit in pregnancy

We have validated a direct radioimmunoassay (RIA) which measures the alpha-subunit of human chorionic gonadotropin (hCG) in pregnancy sera in the presence of large amounts of hCG. The levels of alpha-subunit in 124 sera from normal pregnancy women were measured and compared to the levels of hCG measured by a radioreceptor assay (RRA) which utilizes a rat testicular membrane preparation. Unlike hCG, which peaks at the end of the first trimester, the alpha-subunit continues to rise until 36 weeks of pregnancy. During the first half of pregnancy the levels of alpha-subunit remain less than 100 ng/ml whereas in the second half the levels remain less than 200 ng/ml. Three pathologic pregnancies were also studied; on the basis of the hCG determinations, they could not be differentiated from normal pregnancy. In contrast, all determinations of alpha-subunit were abnormally elevated. The concept that placental dysfunctions would cause an early and abnormally high level of alpha-subunit secretion deserves further investigation.     

Phase I clinical trial of monoclonal anti-human chorionic gonadotropin antibody in women with an ectopic pregnancy

A phase-I clinical trial of a mouse monoclonal anti-human chorionic gonadotropin (hCG) antibody designated as HT13 was conducted in three patients treated for ectopic pregnancy. Doses of 5 and 25 mg of purified antibody were injected into patients. Monoclonal antibody serum levels dropped to 0 within 1 to 5 days. Human antibodies directed against mouse immunoglobulins were not detected at up to 41 days after injection. In one patient, the tubal pregnancy resolved, as confirmed by hCG levels of less than 10 mUl/mL and by tubal patency at hysterosalpingography. The time of resolution was 30 days. In two patients, salpingectomy was performed because of persistence of elevated hCG levels, whereas HT13 had a striking effect on progesterone (P) and estradiol (E2) serum levels. The injection of anti-hCG antibody did not appear to interfere with the subsequent fertility of patients, and two out of three patients later developed a successful pregnancy. While the precise role of antibody injection in the interruption of ectopic pregnancy remains speculative, the injection of monoclonal anti-hCG antibody appears to induce a dramatic decrease in the production of both P and E2.     

Rupture of ectopic pregnancy in women with low and declining serum beta-human chorionic gonadotropin concentrations.

Rupture of tubal EP in two women whose serum beta-hCG levels were low and declining was reported. It suggests that low and falling serum beta-hCG levels are not always associated with resolution of EP and tubal rupture can still occur.     

Disappearance of human chorionic gonadotropin following removal of ectopic pregnancy

A study was undertaken to determine the length of time serum beta-subunit of human chorionic gonadotropin (beta-hCG) could be detected following removal of ectopic pregnancy. Seven patients underwent complete removal of trophoblastic tissue by either salpingectomy or partial resection of the involved fallopian tube. Nine other patients had conservative surgical treatment by either linear salpingostomy or fimbrial expression of the fallopian tube. Serum beta-hCG levels were determined serially in all these patients. The results demonstrate that the initial titer of hCG is a significant factor in determining the length of time that it can be detected in the serum postoperatively. In addition, decreasing titers, conforming to the disappearance curve of hCG, as constructed in this study, are a helpful aid in avoiding further surgery in the group of patients who had a conservative removal of the trophoblastic tissue. Finally, the serum clearance of hCG by radioimmunoassay may take at least up to 24 days after surgery.     

A semiquantitative human chorionic gonadotropin assay for the detection of ectopic pregnancy

Human chorionic gonadotropin (hCG) was measured in 117 serum samples with known quantities of hCG after a dilutional modification of a reliable, simple, and inexpensive qualitative assay for hCG. The modification yielded a semiquantitative assay for hCG with a sensitivity of 5000 mIU/mL. At hCG concentrations below 4000 mIU/mL, the assay had no false-negative or false-positive results; above 6500 mIU/mL, there were also no false-negative or false-positive results. In the range of 4000-6500 mIU/mL, the clinical false-positive rate was 28%. Using the described dilutional modification of this qualitative hCG assay, the test is semiquantitative, and is useful in selecting the appropriate time to perform ultrasound and laparoscopy in women suspected of having an ectopic pregnancy.     

Human chorionic gonadotropin increase in normal early pregnancy

Serial determinations of human chorionic gonadotropin have been used in evaluating early pregnancies. This has been based on linear regression of logarithm-transformed hCG levels. However, these levels are changing in a curvilinear fashion as pregnancy advances. Consequently the simple linear model does not provide a good fit to the data. To define more precisely the normal values for hCG increase, serial determinations were performed on serum samples obtained from 29 patients who were carrying normally advancing pregnancies. Gestational age was established with basal body temperature records. Three gestational age periods were identified each with a linear increase in hCG. This was translated into hCG doubling times and percentage increase over time. These tables may be used to determine if an early pregnancy is advancing normally.     

Prognostic value of human chorionic gonadotropin changes after methotrexate injection for ectopic pregnancy

Because early prediction of clinical outcome (one or more injections or surgery) of methotrexate treatment of ectopic pregnancy could ease the intensity of follow-up and patient compliance required, we studied the relationship between the change in hCG levels after methotrexate injection and outcome in 129 consecutive patients. A 20% decline in hCG levels between days 1 and 4 during methotrexate treatment has a positive predictive value of 97%.     

Human chorionic gonadotropin as a measure of pregnancy duration

Objective

To compare gestational age (GA) estimates in early pregnancy, determined by last menstrual period (LMP), human chorionic gonadotropin (hCG) concentration, ultrasound crown–rump length (Hadlock formula), and ovulation day (luteinizing hormone surge plus 1 day).

Methods

Female volunteers seeking to conceive (at 5 US sites) collected daily early-morning urine for up to 3 menstrual cycles. Pregnant women underwent ultrasound dating scans. Conception cycle urine was quantitatively assessed for luteinizing hormone and hCG. Summary statistics for GA using each reference method were determined (n = 131).

Results

Correlation between GA determined by ultrasound and ovulation day was excellent (maximum difference 10 days); however, pregnancies dated by ultrasound were 3 days advanced. The difference between LMP estimates and estimates based on ovulation day or ultrasound was 9 and 12 days, respectively. A uniform rise in hCG on each day of pregnancy was seen using all reference methods. The accuracy of hCG measurement in determining the week since conception was more than 93%.

Conclusion

Methods for establishing pregnancy duration vary in their accuracy and their GA estimates. The rise in hCG concentration in early pregnancy is uniform and therefore hCG levels provide the most accurate, early estimation of GA in single, viable pregnancies.ClinicalTrials.gov:NCT01077583     

Human chorionic gonadotropin in maternal plasma after induced abortion, spontaneous abortion, and removed ectopic pregnancy

Human chorionic gonadotropin (hCG) in maternal serum was analyzed by a hCG-beta-subunit, radioimmunoassay (hCG-beta-RIA) in 36 cases after induced first-trimester abortion, 35 cases of spontaneous abortion in the first trimester, and in 35 cases of ectopic pregnancy to determine the time between the apparent removal of all trophoblastic tissue by surgical intervention and the disappearance of hCG from the blood. In the cases with induced abortion, hCG was detectable from 16 to 60 days, with a median of 30 days after uterine evacuation, in those with spontaneous abortion from nine to 35 days with a median of 19 days, and in the cases of ectopic pregnancy from one to 31 days with a median of eight, five days after laparotomy d. In the cases with induced abortion, hCG was detectable from 16 to 60 days, with a median of 30 days after uterine evacuation, in those with spontaneous abortion from nine to 35 days with a median of 19 days, and in the cases of ectopic pregnancy from one to 31 days with a median of eight, five days after laparotomy d. In the cases with induced abortion, hCG was detectable from 16 to 60 days, with a median of 30 days after uterine evacuation, in those with spontaneous abortion from nine to 35 days with a median of 19 days, and in the cases of ectopic pregnancy from one to 31 days with a median of eight, five days after laparotomy and removal of the affected tube. There was a significant correlation between the initial hCG levels and the disappearance time in each series. The demonstrated disappearance times are longer than previously recognized, which should be appreciated when hCG is analyzed after termination of early pregnancy.     

The effect of different human chorionic gonadotropin assay sensitivity on screening for ectopic pregnancy

The distribution of human chorionic gonadotropin levels in 184 patients with ectopic pregnancy is examined. The impact of changing the sensitivity of human chorionic gonadotropin testing on the incidence of false negative results is discussed. Pregnancy blood tests with a detection threshold of 200 mIU/ml were associated with an 11.9% incidence of false negative results.