Articles
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786 results found
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
Turner syndrome
Turner syndrome, also known as 45XO or 45X, is the most common of the sex chromosome abnormalities in females.
Epidemiology
The incidence is estimated at 1:2000-5000 of live births, although the in utero rate is much higher (1-2% of conceptions) due to a significant proportion of affected fet...
Article
Third trimester
The third trimester in a gestation is the final trimester in a human pregnancy which is usually taken as extending from 28 weeks and 0 days of gestation to term (~38-40 weeks).
History and etymology
Trimester was first seen in English in 1821, a direct borrowing from the French word trimestre,...
Article
Lambda sign (disambiguation)
There are two described lambda (λ) signs:
lambda sign (twin pregnancy)
lambda sign (sarcoidosis)
Article
Fetal tricuspid regurgitation
Tricuspid regurgitation (TR) (also known as tricuspid insufficiency) is a common finding in imaging of the fetus. Tricuspid regurgitation represents the abnormal backflow of blood into the right atrium during right ventricular contraction due to valvular leakage (i.e. it is a valvulopathy).
Ep...
Article
Abnormally thickened endometrium (differential)
Abnormally thickened endometrium on imaging may occur for a number of reasons which may be categorized based on whether or not they are related to pregnancy. Etiologies may also be classified based on whether the patient is premenopausal or postmenopausal.
Differential diagnosis
Pregnancy-rela...
Article
Congenital rubella syndrome
Congenital rubella syndrome is a spectrum of congenital abnormalities that result from primary maternal infection with the rubella virus. It falls under the TORCH group of infections.
It is important to note that reinfection/reactivation of maternal infection has a significantly lower risk of f...
Article
Pregnancy of uncertain viability
Pregnancy of uncertain viability (PUV) is a term given to an intrauterine pregnancy in a situation where there are not enough criteria (usually on ultrasound grounds) to confidently categorize an intrauterine pregnancy as either viable or a failed pregnancy.
Radiographic features
Ultrasound
...
Article
Cervical cancer (staging)
Staging of cervical cancer can either be based on the TNM or FIGO system.
Classification
Revised FIGO staging of cervical carcinoma (2018)
FIGO no longer includes stage 0 (Tis)
I: confined to cervix uteri (extension to the corpus should be disregarded)
IA: invasive carcinoma only diagnosed ...
Article
Hysterosalpingogram
A hysterosalpingogram (HSG) is a fluoroscopic examination of the uterus and the fallopian tubes, most commonly used in the investigation of infertility or recurrent spontaneous abortions.
Indications
infertility: to assess uterine morphology and tubal patency
Contraindications
pregnancy
act...
Article
Umbilical vein varix
Umbilical vein varix (UVV) refers to a focal dilatation of the umbilical vein.
Epidemiology
Associations
UVVs were initially thought to have a high association with other anomalies which include:
chromosomal anomalies: 5-12% with FIUVV 2,3
Down syndrome
underlying congenital cardiovascul...
Article
Placental abruption
Placental abruption (or abruptio placentae) refers to a premature separation of the normally implanted placenta after the 20th week of gestation and before the 3rd stage of labor. It is a potentially fatal complication of pregnancy and a significant cause of third-trimester bleeding/antepartum h...
Article
Braxton Hicks contractions
Braxton Hicks contractions, also known as practice contractions or false labor, are physiological contractions of myometrium that occur in pregnancy. They are often sporadic and start by ~6 weeks.
Radiographic features
Antenatal ultrasound
It may be seen as a transient change in myometrial th...
Article
Uteroplacental blood flow assessment
Uteroplacental blood flow assessment is an important part of fetal well-being assessment and evaluates Doppler flow in the uterine arteries and rarely the ovarian arteries.
Pathology
In a non-gravid state and at the very start of pregnancy the flow in the uterine artery is of high pulsatility ...
Article
Embryonic growth discordance
Embryonic growth discordance is a term given to a twin growth discordance occurring during the early embryonic period. It is principally manifested by a discrepancy in crown rump length. It is considered independent of the chorionicity of the twins 5.
Epidemiology
Embryonic growth discordance...
Article
Twin reversed arterial perfusion
Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic pregnancies. It develops when the following conditions are present:
1. lack of a well-formed heart in one of the twins (so-called acardiac twin)
2. a superficial artery-to-artery placental anastomosis prov...
Article
Twin anemia polycythemia sequence
Twin anemia polycythemia sequence (TAPS) is considered a variant of the twin to twin transfusion syndrome (TTTS) occurring in monochorionic twin pregnancies.
Epidemiology
TAPS may occur spontaneously in up to 5% of monochorionic twins and may also develop after incomplete laser treatment in tw...
Article
Twin-to-twin transfusion syndrome
Twin-to-twin transfusion syndrome (TTTS) is a potential complication that can occur in a monochorionic twin pregnancy (either MCDA or MCMA).
Epidemiology
This complication can occur in ~10% (range 15-25%) of monochorionic pregnancies, giving an estimated prevalence of ~1:2000 of all pregnanci...
Article
Cervical incompetence
Cervical incompetence refers to a painless spontaneous dilatation of the cervix and is a common cause of second trimester pregnancy failure.
Epidemiology
The estimated incidence varies geographically and generally thought to be around 1-1.5% of all pregnancies 1,15.
Clinical presentation
Typ...
Article
Nuchal translucency
Nuchal translucency is the normal fluid-filled subcutaneous space identified at the back of the fetal neck during the late first trimester and early second trimester (11 weeks 3 days to 13 weeks 6 days).
It should not be confused with the nuchal fold, which is seen in the second trimester.
P...
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