Biomaterial Database

Sexual difference in early fetal crown-rump length versus gestational age in pregnancies arising from in vitro fertilization. 1998

N Tezuka, and M Banzai, and S Sato, and H Saito, and M Hiroi

Department of Obstetrics and Gynecology, Yamagata University School of Medicine, Yamagata City, Japan.

The purpose of this study was to investigate the influence of fetal sex on the crown-rump length (CRL) derived from pregnancies resulting from in vitro fertilization without the uncertain conception dating in the first trimester. With ultrasonography, we performed 334 and 353 examinations, on 88 male and 102 female fetuses, respectively. The relationship between gestational age and fetal CRL was explored with regression analysis: male CRL (mm) = 1.13 x gestational age (days) - 47.39 (r = 0.97), female CRL = 1.11 x gestational age - 46.44 (r = 0.97). These regression lines were mutually included in the 95% confidence intervals for each other. Our results indicate no statistically significant difference in the CRL between the two sexes, being supportive of using the identical fetal CRL criterion regardless of fetal sex for gestational age assessment with ultrasonography in the first trimester of pregnancy.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
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
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
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, 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
D012727	Sex Characteristics	Those characteristics that distinguish one SEX from the other. The primary sex characteristics are the OVARIES and TESTES and their related hormones. Secondary sex characteristics are those which are masculine or feminine but not directly related to reproduction.	Gender Characteristics,Gender Differences,Gender Dimorphism,Sex Differences,Sex Dimorphism,Sexual Dichromatism,Sexual Dimorphism,Characteristic, Gender,Characteristic, Sex,Dichromatism, Sexual,Dichromatisms, Sexual,Difference, Sex,Dimorphism, Gender,Dimorphism, Sex,Dimorphism, Sexual,Gender Characteristic,Gender Difference,Gender Dimorphisms,Sex Characteristic,Sex Difference,Sex Dimorphisms,Sexual Dichromatisms,Sexual Dimorphisms
D016216	Ultrasonography, Prenatal	The visualization of tissues during pregnancy through recording of the echoes of ultrasonic waves directed into the body. The procedure may be applied with reference to the mother or the fetus and with reference to organs or the detection of maternal or fetal disease.	Fetal Ultrasonography,Prenatal Diagnosis, Ultrasonic,Ultrasonography, Fetal,Diagnosis, Prenatal Ultrasonic,Diagnosis, Ultrasonic Prenatal,Prenatal Ultrasonic Diagnosis,Prenatal Ultrasonography,Ultrasonic Diagnosis, Prenatal,Ultrasonic Prenatal Diagnosis,Diagnoses, Prenatal Ultrasonic,Diagnoses, Ultrasonic Prenatal,Prenatal Diagnoses, Ultrasonic,Prenatal Ultrasonic Diagnoses,Ultrasonic Diagnoses, Prenatal,Ultrasonic Prenatal Diagnoses