Investigations for Women Planning Pregnancy

Investigations for all women:

Full blood count (haemoglobin, MCV, platelet count)

Blood group & antibodies

Hepatitis B screening – HBsAg, anti-HBs, anti-HBc (Hep B surface antigen indicates active acute or chronic infection, Hep B surface antibody will be positive if vaccinated or infected, Hep B core antibody indicates current or previous infection; see https://www.racgp.org.au/afp/2012/april/hepatitis-b-serology/ for details regarding the interpretation of results; if results indicate infection add in liver function tests, HBV DNA and HBe antigen and refer for specialist review)

Hepatitis C – anti-HCV (indicates exposure to HCV, indicating current or previous infection; if positive add in liver function tests and HCV RNA PRC and refer for specialist review; (for further information on Hep C, see https://www.racgp.org.au/afp/2013/july/hepatitis-c/)

Human Immunodeficiency Virus – HIV Ab and Ag (if positive seek specialist review; see http://www.sti.guidelines.org.au/sexually-transmissible-infections/hiv for further information)

Syphilis serology – EIA, TPPA or TPHA (conduct a treponema specific test for screening to detect antibodies specific to T.pallidum antigens (ie, EIA, TPPA or THA) then, if positive, follow up with a non-treponemal test (usually RPR) to assess disease activity; see http://www.sti.guidelines.org.au/sexually-transmissible-infections/syphilis for further information; refer for specialist review If positive)

Rubella antibody status – Rubella IgG (if non-immune, vaccinate and advise the patient to avoid pregnancy for the next 28 days)

Varicella zoster antibody status – Varicella IgG (if non-immune, vaccinate and advise the patient to avoid pregnancy for the next 28 days)

Cervical screening test – CST (if this will fall due within the next six months; see pages 7 & 8 of linked pdf for Australian management and referral guidelines http://www.cancerscreening.gov.au/internet/screening/publishing.nsf/Content/C2058A7D155867ACCA2581C400082790/$File/CAN174-Understanding-the-National-Cervical-Screening-Program-Management-Pathway.pdf

Also consider the following investigations:

Chlamydia & Gonorrhoea (endocervical swab or first pass urine; conduct for women at increased risk of infection)

Vitamin D (conduct if the woman is at increased risk of vitamin D deficiency, ie, women with reduced sunlight exposure, veiled women, women who use sunscreen on a regular basis, women with dark skin, women with a child that has rickets, women with a BMI>30)

Iron studies (conduct if the woman is anaemic, has an MCV<85 or if she is at increased risk of iron deficiency, eg, vegetarian, heavy menses)

B12 and folate (conduct if the woman is anaemic or is at increased risk of B12 or folate deficiency, eg, vegetarian).

2hr GTT or HbA1C + fasting BSL (if overweight or any other risk factors for diabetes)

Thalassaemia screening (This can be complicated. If a woman has a family history of any haemoglobinopathy including thalassaemia, it must be investigated; refer to a geneticist and, as a minimum, conduct a FBC, irons studies, B12 and folate on both the woman and her partner. If a patient does not have a family history of any haemoglobinopathy, but has an MCV<85 the most likely cause is iron deficiency; conduct iron studies and, if iron deficiency is present, treat it and repeat the FBC; if the MCV remains low, investigate for thalassaemia; conduct HbEPG, referral to a haematologist is likely to be indicated especially if both the woman and her partner have an MCV<85; see https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1390791/pdf/cbr27_1p027.pdf for a great article on haemoglobinopathies in Australia and how to investigate them)

Screening for genetic conditions – This is complex, confusing for many couples and often expensive; RANZCOG states that “women should be made aware of the availability of screening of low risk women for carrier status of the more common genetic conditions, eg, cystic fibrosis, spinal muscular atrophy, fragile X.”; in reality there are a multitude of different tests available that can test for so many rare genetic disorders that it is inevitable that individuals frequently are carriers for at least one condition. In the section below entities ‘Available Prenatal Genetic Tests’ there is a list of available tests, what they test for and their approximate cost, which is up to date as of January 2018.