During pregnancy, sperm and egg fuse to create a zygote. Among those pregnancies, twinning can occur. Twins can be formed in two different ways: dizygotic (fraternal) or monozygotic (identical).
Dizygotic twins are formed when the mother releases two eggs from the ovaries.
Monozygotic twins are formed when the mother releases a single egg, and the egg later divides into two separate fetuses.
Conjoined twinning only occurs in monozygotic twinning. Instead of going through the entire cell division process, the embryo starts dividing later, and stops. The egg has not finished its dividing, but the process stopped so now the tow fetuses fuse into one, conjoined fetus.
Types of conjoined twins:
• Thoracopagus: most common, these twins are
Dizygotic twins are formed when the mother releases two eggs from the ovaries.
Monozygotic twins are formed when the mother releases a single egg, and the egg later divides into two separate fetuses.
Conjoined twinning only occurs in monozygotic twinning. Instead of going through the entire cell division process, the embryo starts dividing later, and stops. The egg has not finished its dividing, but the process stopped so now the tow fetuses fuse into one, conjoined fetus.
Types of conjoined twins:
• Thoracopagus: most common, these twins are