Obstetric Services

Early Pregnancy Ultrasound

For early pregnancies when the uterus is still within the pelvic brim, transvaginal imaging produces the best detail and diagnostic accuracy. As with gynaecological scans an empty bladder is the only pre-scan preparation required.

An early pregnancy scan (< 10 weeks) is the most accurate time for pregnancy dating and is useful when planning further gestation dependant tests such as the first trimester combined screen. Localizing the early gestational sac within the uterine cavity confidently excludes ectopics in natural pregnancies for women with pelvic pain or who have an increased risk of ectopic pregnancy. For women with hyperemesis in early pregnancy excluding multiple gestation and molar pregnancy is achieved with an early pregnancy scan. The embryonic heart motion can be seen in some pregnancies from as early as six weeks but a live pregnancy may not be verifiable until the seventh week for many women.

First Trimester Fetal Ultrasound

A transabdominal approach is used with transvaginal imaging reserved for those cases where further detail is required. No special bladder preparation is required however some urine in the bladder may be helpful initialy.

This scan has become increasingly popular initially with the nuchal translucency assessment and recently as part of the First Trimester Combined Screen for chromosomal abnormality. An early anatomical survey is also performed at this time which is particularly reassuring for patients with previous major fetal abnormality such as neural tube defect. Pregnancy dating and determining the pregnancy number are both accurately performed at this scan.

Mid Trimester Fetal Ultrasound

The routine fetal anatomical survey is usually scheduled for 18 – 20 weeks of pregnancy. A comfortable, partially filled bladder is helpful for this transabdominal scan.

Routine scan to exclude anomalies detectable by ultrasound, date and number fetuses, localize placenta and assess liquor volume. Markers for chromosomal abnormality when detected are assessed with respect to the individual maternal age related risk profile and prenatal testing with amniocentesis offered after counseling when appropriate.

Third Trimester Fetal Ultrasound

From 22 weeks onwards. A comfortable, partially filled bladder is helpful for this transabdominal scan.

Performed when indicated for the assessment of fetal growth, determining the placental site in those pregnancies at risk of placenta praevia, monitoring cervical length and determining the fetal position. Fetal well being is assessed by umbilical artery doppler studies, liquor volume and fetal movements.

Chorionic Villus Sampling

Ultrasound guided transabdominal procedure for fetal karyotyping usually done from 11 – 14 weeks. Blood group and type confirmation is requested. Anti-D will be administered to Rh – negative patients.

This is the earliest diagnostic test for establishing the normality of the fetal chromosomes and is 100% accurate. Although considered a safe test, there is a slight increase in the overall miscarriage risk of about 1%. The full karyotype result generally takes two weeks but when indicated a FISH analysis which covers the five main chromosomes (13, 15, 21, X and Y) requires only 24 – 48 hours.

Tubal Patency Studies

A new contrast agent (ExEm Foam) has been registered with the TGA for the purpose of tubal patency testing with ultrasound. This replaces the obsolete Levovist for hystero-colpo-salpingography (HyCoSy) and the procedure is otherwise unchanged.

ExEm is a non (embryo) toxic gel foam containing glycerol and hydroxyethylcellulose that has been tested extensively and safely used in medicine (Elam and Elam. 1993; Fale et al., 1998; O’Brien et al., 2003; Berger et al., 2005; Nilforoushan et al., 2005). ExEm gel foam was successfully trialled in the Netherlands for office tubal patency testing achieving adequate uterine cavity filling in 92% of patients (Emmanuel et al, Human Reproduction Nov. 2011) with no serious side effects observed overall. 7% of patients experienced vasovagal discomfort that resolved spontaneously.

We hope to continue to serve those in need of fertility investigations and your patients will be sheduled for ExEm foam salpingogram during days 4 - 10 of a regular menstrual cycle by our reception staff.