Art & Science of Midwifery 4 * Lecture Multiple Pregnancy 2025 11 March 2025

Monozygotic twins

Twins that result from the fertilization of a single ovum by a single sperm, which then divides to form two identical twins.

Dizygotic twins

Twins that result from the fertilization of two separate eggs by two different sperm, resulting in non-identical siblings.

Chorion

The outer membrane that surrounds the embryo and contributes to the formation of the placenta.

Amnion

The innermost membrane that surrounds the embryo, containing the amniotic fluid.

Di chorionic di amniotic twins (Di Di twins)

Twins that each have their own chorion and amnion, typically non-identical.

Twin to twin transfusion syndrome (TTTS)

A condition that occurs in monozygotic twins when blood flow between the twins is uneven, leading to one twin receiving too much blood and the other too little.

Selective fetal reduction

A medical procedure used to reduce the number of fetuses in a high-order multiple pregnancy to improve outcomes for the remaining fetuses.

Congenital twins

Twins that are physically united at birth due to a failure of the embryo to completely split during development.

Fetal hydrops

A serious condition in which an abnormal accumulation of fluid occurs in two or more fetal compartments, such as the abdomen, chest, or under the skin.

Amniotic fluid

The fluid surrounding the fetus in the amniotic sac, providing cushioning and protection.

Placenta previa

A condition in which the placenta partially or completely covers the cervix, which can cause bleeding before or during delivery.

Transfusion

The process of transferring blood or blood products from one individual into another.

Growth restriction

A condition in which a fetus does not grow as expected during pregnancy.

Nuchal translucency scan

An ultrasound test during the first trimester that measures the thickness of the nuchal fold at the back of a fetus's neck, used as a screening test for certain genetic conditions.

Neonatal resuscitation

A set of interventions to assist newborns who experience difficulty at birth, including the provision of warmth, stimulation, and ventilation.

Oligohydramnios

A condition characterized by a deficiency of amniotic fluid, which can lead to complications in pregnancy.