Abnormal 1st Trimester Pathology

Partial Molar Pregnancy

Abnormal fertilization, cystic placenta, and nonviable fetus. Vaginal bleeding, enlarged uterus, severe nausea/vomiting. Elevated hCG levels. Abnormal gestational sac, fetal abnormalities.

Complete Molar Pregnancy/GTD (Gestational Trophoblastic Disease)

Abnormal fertilization, grape-like clusters, no viable fetus. Vaginal bleeding, enlarged uterus, severe nausea/vomiting. Markedly elevated hCG levels. Grape-like clusters without a fetus.

Invasive Mole

Molar pregnancy invading the uterine wall. Persistent elevated hCG, vaginal bleeding. Elevated hCG levels. Invasion into the uterine wall.

Choriocarcinoma

Malignant tumor arising from trophoblastic cells. Hemorrhage, respiratory distress, neurologic symptoms. Extremely elevated hCG levels. Metastases to various organs.

Anembryonic Pregnancy

Gestational sac without embryonic development. Vaginal bleeding, no embryonic development. Low or plateaued hCG levels. Empty gestational sac.

Cornual Ectopic

Ectopic pregnancy in the uterine horn. Abdominal pain, vaginal bleeding. Low rising hCG levels. Ectopic implantation in the cornu of the uterus.

Ovarian Ectopic

Ectopic pregnancy in the ovary. Lower abdominal pain. Low rising hCG levels. Ectopic implantation in the ovary.

Peritoneal/Abdominal Ectopic

Ectopic pregnancy in the abdominal cavity. Abdominal pain. Low rising hCG levels. Ectopic implantation in the abdominal cavity.

Cervical Ectopic

Ectopic pregnancy in the cervix. Vaginal bleeding, pelvic pain. Low rising hCG levels. Ectopic implantation in the cervix.

Heterotopic Pregnancy

Simultaneous intrauterine and ectopic pregnancies. Combines ectopic and intrauterine pregnancy symptoms. Variable hCG levels. Intrauterine and extrauterine gestational sacs.

Pseudogestational Sac/Decidual Cyst

Empty gestational sac-like structure. Mimics intrauterine pregnancy. Variable hCG levels. Empty gestational sac.

Spontaneous Abortion

Naturally occurring termination of pregnancy. Vaginal bleeding, abdominal pain. Decreased hCG levels. Empty or incomplete gestational sac.

Threatened Abortion

Vaginal bleeding without pregnancy loss certainty. Vaginal bleeding without cervical dilation. Stable or decreasing hCG levels. Viable embryo with threatened miscarriage.

Complete Abortion

Passage of all pregnancy products. Passage of all products of conception. Decreased hCG levels. Absence of gestational sac.

Incomplete Abortion

Retained products after incomplete pregnancy loss. Vaginal bleeding, retained products. Variable hCG levels. Presence of retained products.

Lithopedion

Calcified remains of a retained, nonviable fetus. Asymptomatic, calcified fetus. No specific lab findings. Calcified fetal remains.

Inevitable/Impending/Imminent

Abortion

Ongoing pregnancy loss indications. Vaginal bleeding, cervical dilation. Decreasing hCG levels. Gestational sac with imminent miscarriage.

Septic Abortion

Infection complicating an abortion. Fever, abdominal pain, discharge. Elevated WBC, positive blood cultures. Signs of infection in the uterus.

Subchorionic Hemorrhage

Blood collection behind the chorionic membrane. Vaginal bleeding. Normal or stable hCG. Blood collection between chorion and endometrium.

Embryonic Oligohydramnios

Reduced amniotic fluid in early pregnancy. Reduced amniotic fluid. Normal or abnormal depending on cause. Decreased amniotic fluid around the embryo.

1st Trimester Infection

Early pregnancy infection affecting fetal development. Fever, abdominal pain, vaginal discharge. Elevated WBC, positive cultures. Signs of infection in the uterus.

1st Trimester Hemolytic Disease

Maternal-fetal blood group incompatibility causing hemolysis. Anemia, jaundice. Positive Coombs test, high bilirubin. Signs of hemolysis in the fetus.

Placental Hematoma

Blood collection within the placenta. Vaginal bleeding. Variable hCG levels. Blood collection within the placenta.

1st Trimester Hydrops

Fluid accumulation in fetus. Variable hCG levels. Fluid accumulation in multiple fetal compartments.

1st Trimester Hydrancephaly

Absence of cerebral hemispheres. Variable hCG levels. Absence of normal brain tissue.

1st Trimester Anencephaly

Absence of the brain. Variable hCG levels. Absence of cranial vault.

1st Trimester Acrania

Absence of the cranial vault. Variable hCG levels. Absence of the calvaria.

1st Trimester Cephalocele

Herniation of brain tissue. Variable hCG levels. Protrusion of the brain through a defect.

1st Trimester Iniencephaly

Severe retroflexion of the head. Variable hCG levels. Retroflexed head with exposed spinal cord.

1st Trimester Ventriculomegaly

Enlarged lateral ventricles in the brain. Variable hCG levels. Dilated ventricles in the fetal brain.

1st Trimester Holoprosencephaly

Failure of the forebrain to divide. Variable hCG levels. Abnormal development of the cerebral hemispheres.

1st Trimester Dandy Walker Malformation

Cerebellar hypoplasia, hydrocephalus. Variable hCG levels. Enlarged posterior fossa, absent cerebellar vermis.

1st Trimester Spina Bifida

Neural tube defect in the spine. Variable hCG levels. Visible spinal cord defect.

1st Trimester Gastroschisis

Herniation of abdominal contents. Variable hCG levels. Bowel loops outside the abdominal cavity.

1st Trimester Omphalocele

Herniation of abdominal contents within a sac. Variable hCG levels. Abdominal organs enclosed in a membranous sac.

1st Trimester Obstructive Uropathy

Urinary tract obstruction in early pregnancy. Enlarged fetal bladder, oligohydramnios. Variable hCG levels. Distended bladder, dilated ureters.

1st Trimester Cystic Hygroma

Fluid-filled sacs on the neck. Variable hCG levels. Fluid-filled cysts around the fetal neck.

Umbilical Cord Cyst

Cystic structure in the umbilical cord. Usually asymptomatic. Variable hCG levels. Cystic structure in the umbilical cord.

Corpus Luteum Cyst of Pregnancy

Fluid-filled ovarian cyst during pregnancy. Usually asymptomatic. Variable hCG levels Fluid-filled structure in the ovary.

Leiomyoma of Pregnancy

Uterine fibroid present during pregnancy. Usually asymptomatic. Variable hCG levels. Fibroid in the uterus.

Focal Myometrial Contraction

Localized uterine wall contraction during pregnancy. Usually asymptomatic. Variable hCG levels. Localized contraction in the uterine wall.

Oligohydramnios

Reduced amniotic fluid. Variable hCG levels. Decreased amniotic fluid volume.

Polyhydramnios

Increased amniotic fluid. Variable hCG levels. Excessive amniotic fluid volume.

Microcephaly/Microencephaly

Small head and brain size. Variable hCG levels. Abnormally small fetal head.

Megalencephaly

Enlarged head and brain size. Variable hCG levels. Abnormally large fetal head.

Anencephaly

Absence of the brain. Variable hCG levels. Absence of cranial vault.

Acrania/Exencephaly

Absence of the cranial vault. Variable hCG levels. Absence of the calvaria.

Spina Bifida/Occulta/Cystica

Neural tube defect in the spine. Variable hCG levels. Visible spinal cord defect.

Cephalocele

Herniation of brain tissue. Variable hCG levels. Protrusion of the brain through a defect.

Meningocele

Herniation of the meninges. Variable hCG levels. Protrusion of the meninges through a defect.

Myelocele

Herniation of the spinal cord. Variable hCG levels. Protrusion of the spinal cord through a defect.

Myelomeningocele/Meningomyelocele

Herniation of the spinal cord and meninges. Variable hCG levels. Protrusion of the spinal cord and meninges through a defect.

Myeloschisis

Complete absence of the neural tube. Variable hCG levels. Complete failure of neural tube closure.

Arnold Chiari or Chiari II Malformation

Cerebellar herniation through the foramen magnum. Variable hCG levels. Crowding of structures at the base of the skull.

Dandy Walker Malformation/Syndrome

Cystic dilation of the fourth ventricle. Variable hCG levels. Enlarged posterior fossa, absent cerebellar vermis.

Dandy Walker Variant

Mild form of Dandy Walker Malformation. Variable hCG levels. Mild dilation of the fourth ventricle.

Mega Cisterna Magna

Enlarged cisterna magna. Variable hCG levels. Enlarged posterior fossa, normal cerebellum.

Posterior Fossa Arachnoid Cyst

Cyst in the posterior fossa. Variable hCG levels.

Agenesis of the Corpus Callosum (CC)

Absence or partial absence of corpus callosum. Variable, may include intellectual disability, developmental delays. Absence or partial absence of the corpus callosum.

Alobar Holoprosencephaly

Severe facial and brain anomalies. Single-lobed brain structure, facial abnormalities.

Semilobar Holoprosencephaly

Moderate facial and brain anomalies. Partial separation of cerebral hemispheres, moderate facial abnormalities.

Lobar Holoprosencephaly

Mild facial and brain anomalies. Partial separation of cerebral hemispheres, milder facial abnormalities.

Hydranencephaly

Absence of cerebral hemispheres, presence of brainstem. Fluid-filled cranial cavity, absent cerebral hemispheres.

Porencephaly/Porencephalic Cyst

Fluid-filled cavities or cysts in the brain. Cystic areas within the brain tissue.

Schizencephaly

Clefts or cleft-like openings in the cerebral hemispheres. Abnormal openings or clefts in the brain tissue.

Brachycephaly

Shortened head shape. No direct visualization; typically diagnosed after birth based on head shape.

Craniosynostosis

Premature fusion of skull bones, leading to abnormal head shape. Usually diagnosed postnatally, as it involves assessing the fusion of skull bones.

Dolichocephaly

Elongated head shape. No direct visualization; typically diagnosed after birth based on head shape.

Macrocephaly

Enlarged head size. No direct visualization; typically diagnosed after birth based on head size.

Scaphocephaly

Boat-shaped head. No direct visualization; typically diagnosed after birth based on head shape

Kyphosis

Abnormal forward curvature of the spine. No direct visualization; typically diagnosed after birth based on spine curvature.

Scoliosis

Abnormal lateral curvature of the spine. No direct visualization; typically diagnosed after birth based on spine curvature.

Hemivertebrae

Wedge-shaped vertebrae. No direct visualization; typically diagnosed after birth based on spine imaging.

Platyspondylic

Flattened vertebral bodies. No direct visualization; typically diagnosed after birth based on spine imaging.

Cloverleaf Kleeblattschädel Head Shape

Abnormal skull shape resembling a cloverleaf. No direct visualization; typically diagnosed after birth based on skull shape.

Teratoma

Tumor with various tissue types. Variable, depending on location. Elevated tumor markers (AFP, hCG). Solid or cystic mass with various tissue types.

Rachischisis

Failure of neural tube closure in the spine. Visible spinal cord defect.

Cranium Bifidum

Failure of neural tube closure in the skull. Visible skull defect.

Merocephaly

Partial or incomplete development of the head. Abnormal head development.

Fetal Teratoma

Fetal tumor with various tissue types. Variable, depending on location and size. Elevated tumor markers (AFP, hCG). Solid or cystic mass with various tissue types in the fetus.