Twins

Question 1

Dichorionic diamniotic

Answer 1

After 2 cell stage, 0-4 days (before morula)
~25%

Or two fertilized eggs

Question 2

Monochorionic diamniotic

Answer 2

After morula, 4-8 days (before blastocytes)
~75%

“Morula makes chorion”

Question 3

Monochorionic monoamniotic

Answer 3

After blastocytes, 8-12 days (before forming embryonic disc)

Question 4

Monochorionic monoaminiotic conjoined twin

Answer 4

> 13 days, after forming embryonic disc