Items tagged “pregnancy”
43 results found
Anembryonic pregnancy is a form of a failed early pregnancy, where a gestational sac develops, but the embryo does not form. Terminology The term blighted ovum is synonymous with this but is falling out of favor and is best avoided. Clinical presentation The patient may be asymptomatic, pr...
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...
Twin-to-twin transfusion syndrome
Twin-to-twin transfusion syndrome (TTTS) is a potential complication that can occur in a monochorionic (either MCDA or MCMA) twin pregnancy. Epidemiology This complication can occur in ~10% (range 15-25%) of monochorionic pregnancies, giving an estimated prevalence of ~1:2000 of all pregnanci...
The first trimester is defined as the first 13 weeks of pregnancy following the last normal menstrual period (some authors refer to early pregnancy as 0-10 weeks). It can be divided into a number of phases, each of which has typical clinical issues. These phases are: conceptus phase: 3-5 weeks ...
Yolk sac is the first anatomical structure identified within the gestational sac. It plays a critical role in embryonal development by providing nutrients, serving as the site of initial hematopoiesis, providing endocrine, metabolic and immunological functions and contributing to the development...
Fetal heart beat
Fetal heart beat can be detected as early as 34 days (just under 6 weeks) gestation on good quality, high frequency transvaginal ultrasound, as a crown rump length (CRL) of as little as 1-2 mm. If a fetal heartbeat cannot be identified with a CRL ≥7 mm using transvaginal scanning, then embryona...
Published 23 Nov 2009
Published 16 Jan 2010
Published 16 Jan 2010
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...
HELLP syndrome is a pregnancy-related condition and is an abbreviation for: haemolysis elevated liver enzymes and low platelets It is considered a severe and life-threatening form of pre-eclampsia although it can occur without co-existing pre-eclampsia. Epidemiology The estimated inciden...
Acute fatty liver of pregnancy
Acute fatty liver of pregnancy (AFLP) is a rare pregnancy-associated condition that tends to manifest in the 3rd trimester of pregnancy or early postpartum period. Epidemiology The estimated incidence is at around 1:7000-20,000 births. Clinical presentation Patients may present with nausea,...
Antenatal screening and diagnosis are currently available for a few selected genetic conditions, including trisomy 21 (Down syndrome), trisomy 18 (Edward syndrome), trisomy 13 (Patau syndrome) and neural tube defects. For an overview of the conditions and their manifestations, please refer to t...
Twin growth discordance
Twin growth discordance is a term used in obstetric imaging to describe a significant size or weight difference between the two fetuses of a twin pregnancy. To be classified as a growth discordance, some consider that the estimated fetal weight (EFW) of the smaller twin should fall under the 10t...
Wharton jelly refers to the gelatinous substance within the umbilical cord. Gross anatomy Wharton jelly is derived from extra-embryonic mesoderm and is largely made up of mucopolysaccharides (hyaluronic acid and chondroitin sulphate) while containing smaller amounts of fibroblasts and macropha...
Two diameter pocket method
The two diameter pocket (TDP) method is an alternative method of assessing amniotic fluid volumes on ultrasound. However, it is not thought to be a good predictor of adverse neonatal outcome 2. Sonographic assessment According to this method 1,2: TDP <15 cm2: indicative of oligohydramnios TD...
Parturition-induced pelvic instability
Parturition-induced pelvic instability is a rare condition seen in women following vaginal delivery. Epidemiology The incidence of symphyseal rupture after vaginal delivery ranges from one in 600 to one in 30,000 deliveries 1. Predisposing factors include multiparity, complicated delivery, ...
Third trimester gestation
Published 24 Mar 2012
Published 10 Jan 2013
The placenta is a fetal organ of pregnancy, responsible for providing nutrition and oxygen to the fetus as well as excretory functions. Embryology Placenta is formed from fetal and maternal components 2: maternal component: decidua placentalis is the inner portion of the placenta, which is f...