Articles
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786 results found
Article
Fetal atrioventricular block
Fetal atrioventricular block is a form a fetal bradyarrhythmia often classified into
fetal partial atrioventricular block (PAVB)
fetal complete atrioventricular block (CAVB)
Epidemiology
Fetal atrioventricular block is considered rare finding with reported occurrences of around 1:11,000-20,0...
Article
Cystic renal dysplasia
Cystic renal dysplasia refers to a subgroup of congenital anomalies of the kidney and urinary tract characterized by the dysplastic renal parenchyma and formation of cysts. The most severe form is multicystic dysplastic kidney, in which functional renal parenchyma is absent and only undifferenti...
Article
The crisscross sign
The crisscross sign is a fetal ultrasound sign that describes the normal relationship between the ventricular outflows tracts of the fetal heart. The left ventricular outflow tract (LVOT); represented by the take-off of the aorta (Ao) from the left ventricle, is perpendicular (90o) to the right ...
Article
Echogenic fetal bowel
Echogenic fetal bowel is an observation in antenatal ultrasound imaging, in which fetal bowel appears to be brighter than it is supposed to be. It is a soft marker for trisomy 21 and has several other associations. When observed, it needs to be interpreted in the context of other associated abno...
Article
Hemimegalencephaly
Hemimegalencephaly is a rare congenital disorder of cortical formation with hamartomatous overgrowth of all or part of a cerebral hemisphere. This results from either increased proliferation or decreased apoptosis (or both) of developing neurons 2.
Epidemiology
Hemimegalencephaly is a cryptoge...
Article
Early pregnancy
Early pregnancy roughly spans the first ten weeks of the first trimester.
Radiographic features
Antenatal ultrasound
0-4.3 weeks: no ultrasound findings
4.3-5.0 weeks:
possible small gestational sac
possible double decidual sac sign (DDSS)
possible intradecidual sac s...
Article
Missed miscarriage
A missed miscarriage, sometimes termed a missed abortion 3, is a situation when there is a non-viable fetus within the uterus, without symptoms of a miscarriage.
Radiographic features
Ultrasound
Ultrasound diagnosis of miscarriage should only be considered when either a mean gestation sac d...
Article
Postpartum hemorrhage risk factors (mnemonic)
A mnemonic to remember the basic risk factors of postpartum hemorrhage is:
PARTUM
Mnemonic
P: prolonged labor / polyhydramnios / previous C-section
A: APH
R: recent Hx of bleeding
T: twins
U: uterine fibrosis
M: multiparity
Article
Proboscis
Proboscis is a rare congenital anomaly where an anterior appendage-like structure is seen projecting from the midline fetal face/forehead. Depending on the exact location, this has further been classified into various subtypes (e.g. interorbital proboscis).
Pathology
Associations
The presence...
Article
Endometrial thickness
Endometrial thickness is a commonly measured parameter on routine gynecological ultrasound and MRI. The appearance, as well as the thickness of the endometrium, will depend on whether the patient is of reproductive age or postmenopausal and, if of reproductive age, at what point in the menstrual...
Article
Quadruple screening test
The quadruple screening test, also known as the quad screen, AFP Plus quad test or multiple marker screening test, is a maternal antenatal screening blood test that can be used in conjunction with other investigations e.g. ultrasound soft markers, to estimate the risk of aneuploidy 1.
This is ...
Article
Triple screening
Triple screening refers to a screening blood test that is used to screen pregnant women for possible neural tube defects, Down syndrome and trisomy 18 in the developing fetus. It measures:
alpha-fetoprotein
beta hCG
unconjugated estriol
Interpretation
An abnormal test result doesn't indica...
Article
Erb palsy
Erb palsy, also known as brachial plexus birth palsy, is a form of obstetric brachial plexus injury as a result of complications during delivery.
Clinical presentation
The most common cause is due to excessive lateral traction or stretching of the fetal head and neck in opposite directions du...
Article
Dichorionic triamniotic triplet pregnancy
A dichorionic triamniotic (DCTA) triplet pregnancy is a type a multifetal pregnancy where two of the triplets are monochorionic. This type of pregnancy can carry a unique set of complications.
See also
triplet pregnancy
Article
Congenital hypothyroidism
Congenital hypothyroidism (CHT), previously known as cretinism, can be of thyroidal or central (hypothalamic/pituitary) origin and can have a widely diverse molecular etiology.
Clinical presentation
Most children are asymptomatic at birth and are diagnosed after screening. In untreated congeni...
Article
Robinow syndrome
Robinow syndrome is a rare heterogeneous genetic disorder with at least two distinct forms.
Terminology
Fetal face syndrome and Robinow-Silverman syndrome are the other synonyms for this genetic disorder. Formerly it was known as costovertebral segmentation defect with mesomelia 8.
Epidemiolo...
Article
Uterine duplication anomalies
Uterine duplication anomalies are a group of Müllerian duct anomalies where fusion of the Müllerian duct associated structures fail to some degree:
uterus didelphys: class III
bicornuate uterus: class IV (second commonest duplication anomaly)
septate uterus: class V (commonest du...
Article
Gastroschisis
Gastroschisis refers to an extra-abdominal herniation (evisceration) of fetal or neonatal bowel loops (and occasionally portions of the stomach and or liver) into the amniotic cavity through a para-umbilical anterior abdominal wall defect.
Epidemiology
The estimated incidence is around 1-6 per...
Article
Hydrops fetalis
Hydrops fetalis is excessive extravasation of fluid into the third space in a fetus which could be due to heart failure, volume overload, decreased oncotic pressure, or increased vascular permeability. Hydrops is defined as the accumulation of fluid +/- edema involving at least two fetal compone...
Article
Pulmonary hypoplasia
Pulmonary hypoplasia refers to underdevelopment of one or both lungs. This can be rapidly fatal at birth or mild, escaping detection for decades. It is most often secondary to congenital abnormalities that either restrict intrathoracic space or alter pulmonary fluid dynamics.
Epidemiology
Pulm...