Chapter 32 - Fetal Environment and Maternal Complications

The thickness of the placenta should not exceed :

4cm

Chorioangioma

A benign placental tumor

Hemangioma

A benign tumor composed of blood cells

Erthroblastosis fetalis

A conditon in which there is an incompatibility between the fetal and maternal red blood cells

Diethylstibestrol

A drug administered to pregnant women from 1940-1970s to treat threatened abortions and premature labor that has been linked with uterine malformation in the exposed fetus

Cystic adenomatoid malformation

A mass consisting of abnormal bronchial and lung tissue that develops within the fetal chest

Mirror syndrome

A rare disorder in which the mother suffers from edema and fluid buildup similar to her hydropic fetus

Placenta

A vital organ to fetus during pregnancy Normally identified after 10-12 weeks 3 parts : chorionic plate, placental substance, basal layer

Clinical findings of placental abruption:

Abdominal pain (often sudden onset) Possible vaginal bleeding Uterine contraction Uterine tenderness

Marginal cord insertion

Abnormal cord insertion at edge of placenta

Remembering placenta accreta/increta/percreta :

Accreta is associated with Adherence of placenta to myometrium Increta is associated with Invasion of placenta w/in myometrium Percreta is associated with Penetration of placenta thru serosa & possibly other organs

TORCH

Acronym for : Toxoplasmosis Other infxns Rubella Cytomegalovirus Herpes simplex virus

When should placenta be evaluated for previa? And how?

After 20 weeks Empty maternal bladder using TA approach

Succenturiate lobe

An accessory lobe of the placenta

Macrosomia

An estimated fetal weight of greater than the 90th percentile or the neonate that measures more than 4,500g

Polyhydraminos

An excessive amount of amniotic fluid .... more than 25 cm in two planes

Two vessel cord

An umbilical cord with 1 artery and 1 vein Could be assoc w/ other fetal abnormalities and IUGR

What is the most severe type of placental abruption?

Complete abruption Often results in development of retroplacental hematoma

Classifications of placental abruption

Complete abruption - results in retroplacental hematoma Partial abruption - few cm of separation Marginal abruption - subchorionic hemorrhage

Duodenal atresia

Congenital maldevelopment or absence of duodenum

Allantoic cyst

Cyst found within the umbilical cord

Gestational diabetes

Diabetes acquired as a result of pregnancy

Possible causes of thick placenta:

Diabetes mellitus Maternal anemia Infection Fetal hydrops Rh isoimmunization Multiple gestation

Anasarca

Diffuse edema

Placentomegaly

Enlargment of the placenta

Non immune hydrops

Fetal hydrops caused by congenital fetal anomalies & infections

Placental abruption can lead to what?

Fetal hypoxia Maternal death

Multicystic dysplastic kidney disease (MCDKD)

Fetal renal disease thought to be caused by an early renal obstruction ; leads to the development of multiple non communicating cysts of varying sizes in the renal fossa

Vasa previa

Fetal vessels resting over the internal os of the cervix

Chorionic villi

Finger like projections of gestational tissue that attach to the decidualized endometirum and allow the transfer of nutrients from the mother to the fetus

Umbilical vein varix

Focal dilation of the intra-abdominal portion of the umbilical vein

Cesarean section

From of childbirth in which a surgical incision is made through the maternal abdomen to deliver the fetus

Functions of the placenta

Gas transfer; nutrients and oxygen from mother Excretory function Water balance Hormone production ; hCG, estrogen, progesterone Defensive barrier

Wharton jelly

Gelatinous material that is located within the umbilical cord around the umbilical vessels

Cotyledons

Groups or lobes of chorionic vili

Multiparity

Having had several pregnancies

U/s findings placental abruption :

Hematoma located either at the edge of the placenta or between the placenta and the myometrium

Maternal conditions linked to development of placental abruption :

Hypertension Preeclampsia Cocaine use Cigarette smoking Poor nutrition Trauma

U/s findings vasa previa

Identification of vessels over the internal os of the cx w/ color doppler Velamentous cord insertion

Placenta increta

Invasion of the placenta within the myometrium

Posterior urethral valves

Irregular thin membranes of tissue located within the male posterior urethra that does not allow urine to exit the urethra

Oligohydraminos

Lower than normal amount of amniotic fluid... less than 10 cm in two planes

What is the most common placental abruption identified with u/s?

Marginal abruption (sub chorionic hemorrhage)

Both a thick/large placenta (placentomegaly) and a thin placenta are associated with what?

Maternal and/or fetal abnormalities

Nongravid

Not pregnant

Placenta percreta

Penetration of the placenta through the uterine serous a and possibly into adjacent pelvic organs

Complete (total) previa

Placenta covers the internal os completely

Marginal previa

Placenta lies at edge of internal os

What is a common cause of painless vaginal bleeding in the 2nd & 3rd trimester?

Placenta previa

U/s findings placenta accreta, increta, percreta

Placenta previa (frequent associated findings) Loss of the normal hypoechoic interface between the placenta and the myometrium

Bilobed placenta

Placenta that consists of two separate discs of equal size

Abruption placenta

Placental abruption

Preeclampsia

Pregnancy-induced maternal high blood pressure & excess protein in urine after 20 weeks gestation

Clinical findings placenta previa

Previous C section or uterine surgery Painless vaginal bleeding Possibly asymptomatic Hx of multiparty Previous abortion Advanced maternal age

Clinical findings of placenta accreta, increta, percreta:

Previous c section or uterine surgery Painless vaginal bleeding if placenta previa is present Possibly ASX

Vernix

Protective fetal skin covering

Proteinuria

Protein in the urine

Premature rupture of membranes

Rupture of the amniotic sac prior to the onset of labor; increases risk of fetal infection or injury.

Twin-to-Twin Transfusion Syndrome (TTTS)

Shunting of venous or arterial blood from one twin to another through placental circulation

Microcephaly

Small head

Placenta accreta

The abnormal adherence of the placenta to the myometrium in an area where the decidua is either absent or minimal

Velamentous cord insertion

The abnormal insertion of the umbilical cord into the membranes beyond the placental edge

Anemia

The condition of having a deficient number of red blood cells

Umbilical vein

The easel of the umbilical cord that carries oxygenated blood from the placenta to the fetus

Bilateral renal agenesis

The failure of both kidneys to develop in the fetus

What is the risk with vasa previa ?

The fetal vessels resting over the internal os of the cx are prone to rupture as the cx dilates which can lead to exsanguination of fetus (bleeding out)

Neonatal period

The first 28 days of life

Cervical incompetence

The painless dilation of the cervix in the second or early third trimester

Cerclage

The placement of sutures within the cervix to keep it closed

Funneling (cervical)

The result of the premature opening of the internal os and the subsequent bulging of the membranes into the dilated cervix

Blastocyst

The stage of conceptus that implants within the decidualized endometrium

Lower uterine segment

The term used for the isthmus during pregnancy

Philtrum

The vertical groove seen between the upper lip and the nasal septum

Exsanguination

Total blood loss ; to bleed out

Umbilical arteries

Two vessels of the umbilical cord that carry deoxygenated blood from the fetus to the placenta

What are some risks assoc w/ circumvallate placenta?

Vaginal bleeding Placental abruption

Retained products of conception (RPOC)

When additional placental tissue remains within the uterus after the bulk of the placenta has been delivered

Placenta previa

When the placenta covers or nearly covers the internal os of the cervix

Shoulder dystopia

When the shoulder of the fetus cannot pass through the birth canal during pregnancy

Gestational trophoblastic disease

a disease associated with an abnormal proliferation of the trophoblastic cells during pregnancy; may also be referred to as molar pregnancy

Biophysical profile

a method of fetal monitoring with sonography to produce a numeric scoring system that predicts fetal well-being

Fetal hydrops

an abnormal accumulation of fluid in at least two fetal body cavities

Circumvallate placenta

an abnormally shaped placenta caused by the membranes inserting inward from the edge of the placenta, producing a curled-up placental shape

What is the most common placental tumor ?

chorioangioma

Nuchal cord

condition of having the umbilical cord wrapped completely around the fetal neck

Esophageal atresia

congenital absence of part of the esophagus

Immune hydrops

fetal hydrops due to Rh incompatibility

Meconium

fetal stool that is composed of fetal skin, hair, amniotic fluid, and bile

Placental grading

grade 0- smooth chorionic plate, homogenous texture Grade 1- subtle indentations on chorionic plate, some small calcifications w/in placental substance Grade 2- moderate indentations in chorionic place w/ "comma like" calcifications in placental substance Grade 3- prominent indentations in chorionic plate extends to basal layer, diffuse echogenic & anechoic areas noted w/in placental substance

Low lying previa

placental edge extends into the lower uterine segment but ends more that 2 cm away from the internal os

Venous lakes

pools of maternal blood within the placental substance

Decidua basalis

the endometrial tissue at the implantation site, and the maternal contribution of the placenta

Estimated fetal weight

the fetal weight based on sonographic measurements

Chorion frondosum

the part of the chorion, covered by chorionic villi, that is the fetal contribution of the placenta

Partial previa

the placenta partially covers the internal os.

Vitelline duct

the structure that connects the developing embryo to the secondary yolk sac

Postpartum

time directly after giving birth and extending to about 6 weeks

Possible causes of thin placenta:

*Diabetes mellitus (long standing) *IUGR *Placental insufficiency *Polyhydramnios *Pre-eclampsia *Small for dates fetus