Biomaterial Database

Conceptual age and ultrasound measurements of gestational sac and crown-rump length in in vitro fertilization pregnancies. 1988

I K Rossavik, and G O Torjusen, and W E Gibbons

Department of Obstetrics and Gynecology, University of Oklahoma Health Health Sceinces Center, Okalhoma City 73190.

The growth of the mean gestational sac diameter and the crown-rump length were evaluated from individual series and found to be linear in singletons, twins, and triplets from an in vitro fertilization program as well as in pregnancies with ovulation determined from serial ultrasound folliculograms. No difference in growth rate between the different groups was observed. The 95% confidence limits were 7.7 days before and 7.5 days after mean for the gestational sac diameter, and 5.2 days before and 5.6 days after mean for the crown-rump length. These limits, used together with new linear equations, create less anxiety and less unnecessary surgical intervention than current nonlinear standards when conceptual age is known and the gestational sac or the crown-rump length are too small to be measured.

UI	MeSH Term	Description	Entries
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
D005307	Fertilization in Vitro	An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.	Test-Tube Fertilization,Fertilizations in Vitro,In Vitro Fertilization,Test-Tube Babies,Babies, Test-Tube,Baby, Test-Tube,Fertilization, Test-Tube,Fertilizations, Test-Tube,In Vitro Fertilizations,Test Tube Babies,Test Tube Fertilization,Test-Tube Baby,Test-Tube Fertilizations
D005314	Embryonic and Fetal Development	Morphological and physiological development of EMBRYOS or FETUSES.	Embryo and Fetal Development,Prenatal Programming,Programming, Prenatal
D005321	Extraembryonic Membranes	The thin layers of tissue that surround the developing embryo. There are four extra-embryonic membranes commonly found in VERTEBRATES, such as REPTILES; BIRDS; and MAMMALS. They are the YOLK SAC, the ALLANTOIS, the AMNION, and the CHORION. These membranes provide protection and means to transport nutrients and wastes.	Fetal Membranes,Extra-Embryonic Membranes,Extra Embryonic Membranes,Extra-Embryonic Membrane,Extraembryonic Membrane,Fetal Membrane,Membrane, Extra-Embryonic,Membrane, Extraembryonic,Membrane, Fetal,Membranes, Extra-Embryonic,Membranes, Extraembryonic,Membranes, Fetal
D005323	Fetal Monitoring	Physiologic or biochemical monitoring of the fetus. It is usually done during LABOR, OBSTETRIC and may be performed in conjunction with the monitoring of uterine activity. It may also be performed prenatally as when the mother is undergoing surgery.	Monitoring, Fetal,Fetal Monitorings,Monitorings, Fetal
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
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014310	Triplets	Three individuals derived from three FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother.	Triplet
D014427	Twins	Two individuals derived from two FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother. Twins are either monozygotic (TWINS, MONOZYGOTIC) or dizygotic (TWINS, DIZYGOTIC).	Twin
D014463	Ultrasonography	The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.	Echography,Echotomography,Echotomography, Computer,Sonography, Medical,Tomography, Ultrasonic,Ultrasonic Diagnosis,Ultrasonic Imaging,Ultrasonographic Imaging,Computer Echotomography,Diagnosis, Ultrasonic,Diagnostic Ultrasound,Ultrasonic Tomography,Ultrasound Imaging,Diagnoses, Ultrasonic,Diagnostic Ultrasounds,Imaging, Ultrasonic,Imaging, Ultrasonographic,Imaging, Ultrasound,Imagings, Ultrasonographic,Imagings, Ultrasound,Medical Sonography,Ultrasonic Diagnoses,Ultrasonographic Imagings,Ultrasound, Diagnostic,Ultrasounds, Diagnostic