6 weeks' gestation is predictive of spontaneous single fetal loss in the first trimester, regardless of chorionicity
, a retrospective study has found.
Ultrasound scanning may help in assessing the zygosities of twins by determining the fetal sex, chorionicity
, and amnionicity of the 2 gestations (2).
These include either establishment or confirmation of precise gestational age, early recognition and determination of chorionicity
in multiple gestations, identification of many major congenital abnormalities -- including cystic hygromas that are associated with an up-to-50% incidence of chromosomal anomalies.
Multifetal pregnancy reduction is best performed in the first trimester of pregnancy after aneuploidy screening and confirmation of chorionicity
, thus ensuring that the remaining fetus(es) is/are healthy.
Conception and foetal growth are influenced by the type of conception (natural or assisted/ artificial), singleton or multiple gestation including zygosity/ chorionicity
, 'maternal effect ', maternal nutritional supplementation and timing in gestation, placental function/ placental nutrition and its determinants and the relevant hormones including insulin, insulin-like Growth Factor I, insulin-like Growth Factor II and Leptin among others.
Equally important is the 11-13 week detailed fetal ultrasound exam performed to detect fetal anomalies including about 40% of heart defects, determine the chorionicity
for multiple pregnancies, and to make other observations about fetal development.
SAN FRANCISCO--The physician is responsible for knowing the chorionicity
of a pregnant patient's twins, so if you don't offer diagnostic ultrasound or can't make the diagnosis yourself, refer the patient to someone who can.
The management of selective IUGR depends on the chorionicity
We found no statistically significant association between the concentration of fetal DNA in the maternal circulation and chorionicity
in MM pregnancies, which does not help in elucidating the origin of cell-free fetal DNA in maternal plasma.
must be determined, nutrition must be optimized, cervical length should be measured, and attention should be paid during the late gestational period to careful surveillance and the timing of delivery.
is best determined in the first trimester of pregnancy.
The American Journal of Obstetrics & Gynecology ran a striking editorial about the significance of establishing chorionicity
by first-trimester ultrasound in multiple gestations.