This section discusses the evidence for offering women a range of tests as part of usual care.
Recommendations are based on evidence about the diagnostic accuracy of available tests, the effectiveness of interventions to prevent mother-to-child transmission of infection or other effects on the unborn baby, and the availability of treatments.
For notifiable infections (HIV, hepatitis B, hepatitis C, rubella, syphilis), diagnoses are required to be reported to the National Notifiable Diseases Surveillance System. This allows analysis of trends in jurisdictions and groups at risk, although data quality varies for the different conditions and reporting of Indigenous status is incomplete in some States and for some conditions. Evidence on the prevalence and incidence of other conditions is generally from observational studies and may not be representative of the Australian population or groups within the population. While incidence or prevalence data are not always available, each chapter includes a brief discussion that aims to give health professionals an indication of the likelihood that women in their community will be affected.
Summary of advice on tests offered to all women during pregnancy
Tests are offered in the context of engagement and consultation with women. Health professionals must use standard precautions for infection prevention and control. Tests evolve with advances in technology and health professionals must keep up-to-date with the latest developments and evidence.
Anaemia
Haemoglobin concentration: Full blood count and consideration of possible nutrient deficiencies for women with low haemoglobin concentrations
Haemoglobin disorders
Full blood count: Further investigations for women with abnormal red cell indices, family history or origin in a high-risk country
Gestational diabetes
Plasma glucose (fasting or following 75 g glucose loading): Treatment of gestational diabetes reduces the risk of perinatal complications
HIV**
EIA and Western blot: Antiretroviral treatment in pregnancy reduces risk of transmission
Hepatitis B**
Blood test for HbsAg#: Vaccination of newborn reduces risk of infection
Hepatitis C**
Blood test for hepatitis antibody / RNA if antibodies detected: Avoiding certain interventions among women who test positive reduces risk of mother-to-child transmission and direct-acting antiviral therapy used postpartum (or post breastfeeding) is highly curative protecting future pregnancies
Syphilis#
Treponemal assay confirmed with an alternative treponemal assay: Treatment benefits mother and prevents congenital syphilis
Rubella
Blood test for rubella antibody: Vaccination after birth protects future pregnancies. Inadvertent vaccination in early pregnancy is highly unlikely to harm the baby
Asymptomatic bacteriuria
Midstream urine culture: Treatment reduces risk of pyelonephritis
Group B streptococcus*
Self-collected vaginal-rectal swab culture: Identification of colonisation allows treatment during labour to reduce transmission to the baby
* According to organisational policy.
** Specialist care and psychosocial support are required for women with HIV, hepatitis B or hepatitis C.
# Psychosocial support, partner testing and contact tracing needed for women with sexually transmitted infections.
EIA=enzyme immunoassay; HbsAg=hepatitis B surface antigen; HIV=human immunodeficiency virus.
Considerations before testing
Before tests are carried out, it is essential that:
- women are informed that it is their choice to have tests
- women are able to give informed consent: verbal discussion should cover the reasons for testing, harms and benefits and associated treatments and be supported by appropriate resources (eg written materials, audio or video) and efforts should be made to ensure that women have understood the information they are given
- women have opportunities to ask questions about tests and treatments
- women are reassured that test results remain confidential (unless the condition is notifiable, in which case they are given information about the notification process)
- discussions about consent are documented by the health professional involved
- women who decline testing are offered the opportunity to discuss any concerns they may have without being coerced to reconsider the test
- there are processes for follow-up of women with a positive test result, their babies and, in some situations, partners.
Discussion of testing should be approached with sensitivity, particularly when there is a potential for testing to raise maternal anxiety or if testing is for a sexually transmitted infection.
Considerations after a positive test result
- Psychosocial support: Diagnosis of a condition that may affect pregnancy and/or the health of the baby can be distressing, particularly if there are no interventions that can change outcomes. Women should be given information about available supports and assisted to access these.
- Referral for specialist care: For some conditions, such as haemoglobin disorders and thyroid dysfunction, specialist involvement will be required.
- Sexually transmitted infections: If a sexually transmitted infection is identified, there is an increased risk of other sexually transmitted infections. Testing and treatment of sexually transmitted infections and contact tracing have public health benefits as transmission to partners is reduced.
- Blood-borne infections: Specific supports are likely to be required for women identified as using intravenous drugs.
- Notification: State/Territory legislation on notification of communicable diseases must be followed.
Type of test
The tests discussed in this section are those currently in use in Australia. With continuous advances in technology and testing, techniques change rapidly. The most appropriate test may also depend on the clinical setting.
Testing in rural and remote areas
It is acknowledged that in Australia, access to tests may vary (eg due to distance from pathology services), storing tests and samples appropriately may be challenging (eg due to high temperatures or humidity) and there may be difficulties in recalling women to receive test results. In these situations, resources should be focused on responding to local needs (eg ensuring that tests are available to identify highly prevalent conditions).