dizygotic twins Flashcards
1
Q
from where do dizygotic twins arise?
A
from 2 or more eggs and 2 or more sperm
2
Q
frequency?
A
8-10/1000. taiwan 1.4/1000, nigeria 45/1000
3
Q
how does incidence of dizygotic twinning increase?
A
with maternal age up to about age 37
4
Q
what influences dizygotic twinning?
A
familial (genetic) tendencies
5
Q
how are dizygotic amnions?
A
dizygotic twins have two separate amnions because they are the product of separate blastocysts
6
Q
how many chorionic membranes are there?
A
two, which may fuse later in gestation
7
Q
how many placentas in dizygotic twins?
A
there are two placentas which may fuse depending on the relative positions of implantations and placental growth.
