Biomaterial Database

The intrauterine growth of the biparietal diameter of twins. 1979

P H Persson, and L Grennert

A series of 978 repeated ultrasonic measurements of the fetal biparietal diameter (BPD) assessed the growth of 119 twin pairs during the second half of pregnancy. The mean BPD values for each gestational week were close to the mean values for singletons. From the 32nd week, the BPD growth curves for twins deviated from that for singletons. The second twins' growth curve ran consistently below that of the first and fell away more from the 32nd week on. In 80% of the measurements, the first twin (defined as the twin in, or close to, the pelvic inlet) was the one with the largest BPD. The intrapair difference in BPD had no correlation to the intrapair difference in body length, head circumference, or birth weight. In 91 of the 119 twin pairs, zygosity was settled by sex, histological examination of placenta, or blood grouping. The longitudinally compiled BPD growth curves (678 BPD determinations) showed the curve for dizygotic twins consistently running above that of the monozygotic twins. The BPD differences between the first and the second twin remained also within mono- and dizygotic groups of twins.

UI	MeSH Term	Description	Entries
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D010294	Parietal Bone	One of a pair of irregularly shaped quadrilateral bones situated between the FRONTAL BONE and OCCIPITAL BONE, which together form the sides of the CRANIUM.	Bone, Parietal,Bones, Parietal,Parietal Bones
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
D011272	Pregnancy, Multiple	The condition of carrying two or more FETUSES simultaneously.	Multiple Pregnancy,Multiple Pregnancies,Pregnancies, Multiple
D001724	Birth Weight	The mass or quantity of heaviness of an individual at BIRTH. It is expressed by units of pounds or kilograms.	Birthweight,Birth Weights,Birthweights,Weight, Birth,Weights, Birth
D001835	Body Weight	The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.	Body Weights,Weight, Body,Weights, Body
D002508	Cephalometry	The measurement of the dimensions of the HEAD.	Craniometry
D005260	Female		Females
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