Biomaterial Database

Doubling times of human chorionic gonadotropin increase in early viable intrauterine pregnancies. 1985

D E Pittaway, and R L Reish, and A C Wentz

Although the doubling time of serum human chorionic gonadotropin has been assumed to be constant in early viable intrauterine pregnancy (prior to 6 to 7 weeks after menses), the range has varied between 1.4 and 3.5 days in the literature. To evaluate this variability of the doubling time, the mean doubling times at different ranges of human chorionic gonadotropin concentrations were determined in 49 normal pregnancies, and the doubling times at different intervals of gestation from both the day of the basal body temperature shift and the last menstrual period. The data obtained from the three different methods indicate that the doubling time of human chorionic gonadotropin is not constant but rather increases with increasing human chorionic gonadotropin concentration or gestational age. In addition, statistical analysis of the semilogarithmic plots of serum human chorionic gonadotropin concentrations indicated that the exponential rate of increase of serum human chorionic gonadotropin significantly decreases with gestational age. Since serum human chorionic gonadotropin doubling times increase and the exponential rate decreases with gestational age, estimates of normal values should be established for small sampling ranges and/or short intervals of gestation.

UI	MeSH Term	Description	Entries
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011261	Pregnancy Trimester, First	The beginning third of a human PREGNANCY, from the first day of the last normal menstrual period (MENSTRUATION) through the completion of 14 weeks (98 days) of gestation.	Early Placental Phase,Pregnancy, First Trimester,Trimester, First,Early Placental Phases,First Pregnancy Trimester,First Pregnancy Trimesters,First Trimester,First Trimester Pregnancies,First Trimester Pregnancy,First Trimesters,Phase, Early Placental,Phases, Early Placental,Placental Phase, Early,Placental Phases, Early,Pregnancies, First Trimester,Pregnancy Trimesters, First,Trimesters, First
D012016	Reference Values	The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.	Normal Range,Normal Values,Reference Ranges,Normal Ranges,Normal Value,Range, Normal,Range, Reference,Ranges, Normal,Ranges, Reference,Reference Range,Reference Value,Value, Normal,Value, Reference,Values, Normal,Values, Reference
D012044	Regression Analysis	Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.	Regression Diagnostics,Statistical Regression,Analysis, Regression,Analyses, Regression,Diagnostics, Regression,Regression Analyses,Regression, Statistical,Regressions, Statistical,Statistical Regressions
D005260	Female		Females
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D006063	Chorionic Gonadotropin	A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).	Chorionic Gonadotropin, Human,HCG (Human Chorionic Gonadotropin),Biogonadil,Choriogonadotropin,Choriogonin,Chorulon,Gonabion,Human Chorionic Gonadotropin,Pregnyl,Gonadotropin, Chorionic,Gonadotropin, Human Chorionic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor