Antenatal screening

Last updated: Friday, 16, July, 2010
Key InformationAppropriate Tests

National guidelines may vary from country to country.

Routine at first antenatal visit, before 20 weeks

Tests recommended: FBC; blood group and blood group antibody screen; rubella antibody status, hepatitis B virus serology (HBsAg), hepatitis C serology (HCV) antibodies, HIV antibodies and syphilis serology (TPHA or TPPT); Vitamin D.

Urine microscopy and culture.

Other tests to consider: Cervical cytology; screening for haemoglobinopathies; varicella antibodies.

Tests after the first visit: Obstetric ultrasound before 20 weeks gestation; screening for Down syndrome (see link below).

Routine at 26-28 weeks

FBC (Haemoglobin and platelet count).

Blood group antibody screen.

See also Haemolytic disease of the newborn.

Glucose challenge test. NB the urine glucose is of no value in the detection of gestational diabetes mellitus.

Repeat syphilis serology in high risk populations.

Routine at 30-36 weeks

FBC, blood film. Group B streptococcus screening.

If high risk for infection

Genital swab for Chlamydia trachomatis, Neisseria gonorrhoeae; HIV antibodies.

If the patient has recurrent genital ulcers, thought to be due to Herpes simplex infection, the diagnosis should be confirmed by virus detection, culture; documentation enables a more informed decision as to the need for Caesarean section if lesions are still present at the onset of labour.

Selective testing for cytomegalovirus and toxoplasmosis should only be considered for women at substantially increased risk of acquiring such infections, and ideally this testing should be done prior to pregnancy.

Additional tests, if appropriate

Down syndrome antenatal risk testing ('triple test'), Alpha fetoprotein - serum (neural tube defects).

Reference

College Statement: The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Antenatal Screening Tests. Statement: C-Obs3, November 2006 http://www.ranzcog.edu.au/publications/statements/C-obs3.pdf

Diagnosis of Gestational Diabetes. The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Antenatal Screening Tests. Statement: C-Obs7, November 2006 http://www.ranzcog.edu.au/publications/index.shtml

Prenatal Screening for Trisomy 21 (Down Syndrome), trisomy 18 (Edward Syndrome) and neural tube defects. The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Antenatal Screening Tests. Statement: C-Obs4, July 2007 http://www.ranzcog.edu.au/publications/index.shtml

Guidelines for Blood Group and Antibody Screening in the Antenatal and Perinatal Period. http://www.anzsbt.org.au/publications