Biomaterial Database

Accuracy of gestational age estimation by means of fetal crown-rump length measurement. 1993

S Daya

Department of Obstetrics and Gynaecology, McMaster University, Hamilton, Ontario, Canada.

OBJECTIVE The purpose of this study was to develop a gestational age table by means of crown-rump length measurements in the first trimester in pregnancies conceived through in vitro fertilization. METHODS Ninety-four infertile women with singleton intrauterine pregnancies resulting from in vitro fertilization underwent ultrasonographic examinations in the first trimester. The relationship between gestational age (calculated with the day of oocyte retrieval used as day 14) and the crown-rump length was explored with regression analysis. RESULTS A quadratic model demonstrated the best fit to the data, indicating a curvilinear relationship between crown-rump length and gestational age. Estimates of gestational age with crown-rump length measurements between 40 and 60 mm were observed to be similar to published tables, but outside this range the tables either overestimate or underestimate the true gestational age. CONCLUSIONS A more accurate equation for gestational age estimation with crown-rump length measurements in early pregnancy has been developed with in vitro fertilization pregnancy data.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008598	Menstruation	The periodic shedding of the ENDOMETRIUM and associated menstrual bleeding in the MENSTRUAL CYCLE of humans and primates. Menstruation is due to the decline in circulating PROGESTERONE, and occurs at the late LUTEAL PHASE when LUTEOLYSIS of the CORPUS LUTEUM takes place.
D010060	Ovulation	The discharge of an OVUM from a rupturing follicle in the OVARY.	Ovulations
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
D001827	Body Height	The distance from the sole to the crown of the head with body standing on a flat surface and fully extended.	Body Heights,Height, Body,Heights, Body
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