Items tagged “pregnancy”
26 results found
Article
Anembryonic pregnancy
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 favour and is best avoided.
Clinical presentation
The patient may be asymptomatic, p...
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
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
First trimester
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
...
Article
Yolk sac
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 haematopoiesis, providing endocrine, metabolic and immunological functions and contributing to the developmen...
Article
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...
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
HELLP syndrome
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...
Article
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,...
Article
Antenatal screening
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...
Article
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...
Article
Wharton jelly
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...
Article
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...
Article
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, ...
Article
Placenta
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...
Article
Umbilical cord
The umbilical cord is a fetal organ that connects the placenta to the developing fetus and is a vital passage for nutrients, oxygen and waste products to and from the fetus.
Gross anatomy
The umbilical cord inserts into the centre of the placental bulk and into the fetus at the umbilicus. Vari...
Article
Trauma in pregnancy
Trauma is a leading cause of mortality in pregnancy. Pregnancy increases the incidence and severity of abdominal trauma in females.
Epidemiology
Trauma affects up to 7% of pregnancies, and the incidence of pregnancy in level 1 trauma patients is estimated to be ~2% 1.
Pathology
Aetiology
...
Article
Hamman syndrome
Hamman syndrome, also known as Macklin syndrome, refers to spontaneous pneumomediastinum with subcutaneous emphysema.
Epidemiology
It is a rare entity most often encountered in young adults, particularly in the peri- and postpartum periods 3.
Clinical presentation
Hamman syndrome is most com...
Article
Chorionic bump
Chorionic bump is a finding that can be uncommonly seen in a first-trimester scan. It may represent a small haematoma bulging into the gestational sac or an anembryonic (failed) second pregnancy that is being resorbed. It is also seen in some patients undergoing infertility treatment.
Epidemiol...
Article
Dystocia of shoulder
Shoulder dystocia (SD) refers to the failure of the shoulder to be delivered during childbirth and the need for extra-obstetric manoeuvres to facilitate their passage after normal smooth gentle downward traction has failed. Dystocia literally means difficult labour.
Epidemiology
The incidence ...