Pre-Conception Testing

RANZCOG recommend all women planning a pregnancy see their GP for a health check to ensure any pre-existing conditions or medical problems are effectively managed. Your patient’s prenatal health is critical to the outcome of their pregnancy and to the lifetime health of their baby. Below, we highlight some important pre-conception pathology tests.

 

Haematology

  • FBE (full blood examination): This test gives a good indication of general health, including haemoglobin and platelet levels. Sufficient haemoglobin is important during pregnancy as haemoglobin provides oxygen to the unborn baby.
  • Iron studies: Measures serum iron, ferritin, and transferrin, and can be used as a baseline for further monitoring during pregnancy. Checking patient iron levels prior to pregnancy is important, as iron deficiency is a common problem in pregnant women and can lead to fatigue and anaemia if left untreated.
  • Haemoglobin electrophoresis: Tests for conditions including thalassemia or sickle cell anaemia.
 

Biochemistry

  • Folate: To check that folate levels are sufficient. Folate is essential for the healthy development of the baby’s neural tube; insufficient levels can result in neural tube defects, including spina bifida. Folic acid should be taken starting at least 1 month prior to pregnancy and throughout the first 3 months of pregnancy (RANZCOG guidelines).
  • Vitamin D: To check that vitamin D levels are sufficient. If a patient has vitamin D deficiency, their body may not correctly absorb calcium, affecting both their bone health and also the developing bones of their baby.
  • LFT (liver function test) and U&E (kidney function test): To be used as baseline for further monitoring during pregnancy. Abnormal results during pregnancy can be the result of pregnancy-specific disorders such as pre-eclampsia.
 

Hormones

  • TSH (thyroid-stimulating hormone): Thyroid hormone imbalances can affect a woman’s ovulation, and therefore her fertility. Good maternal thyroid function is critical for the baby’s brain development, especially during the first trimester when the baby is dependent on the mother’s supply of thyroid hormone.
  • FSH (follicle-stimulating hormone) & LH (luteinizing hormone): These reproductive hormones help with maintaining a healthy menstrual cycle and ovulation.
  • AMH (anti-Müllerian hormone): To check the patient’s ovarian reserves. For more information on fertility testing at Clinical Labs, click here.
 

Microbiology

  • Chlamydia and gonorrhoea: Both bacterial, and often asymptomatic, these STIs can lead to major complications including infertility if left untreated. Chlamydia and gonorrhoea can also cause pelvic inflammatory disease (PID), which is a major cause of tubal pregnancy.
  • Cervical Screening Test: RANZCOG recommend completing the Cervical Screening Test at the pre-conception health check, where relevant. This test is used to detect human papillomavirus (HPV), which is a common virus that can change the cells in the cervix and, in rare cases, can develop into cervical cancer.
 

Serology

  • Measles, mumps, rubella, and varicella zoster, hepatitis B, diphtheria, tetanus and pertussis: Immunity should be checked for these illnesses. Immunisation should be considered for women without complete immunity for hepatitis B, rubella and varicella (RANZGOG guidelines). Hepatitis B is highly contagious and can be easily passed on to the baby at the time of delivery. Rubella and varicella can cause life-long disabilities in unborn babies.
  • HIV: A baby born to a mother who is HIV-positive has about a 1 in 4 chance of catching HIV without treatment. However, the likelihood of transmission can be reduced to almost zero with appropriate interventions.
  • Syphilis: Identification and treatment of syphilis before pregnancy is important, as congenital syphilis can lead to miscarriage, stillbirth and future health issues for the baby.
  • Toxoplasmosis antibodies: A very uncommon infection in Australia. Increases the risk of miscarriage or damage to the baby’s nervous system.
  • Parvovirus antibodies: If a patient contracts this infection while they are pregnant, the likelihood of a miscarriage increases dramatically.
  • Cytomegalovirus antibodies: CMV is the most common congenital infection in Australia. If the mother is infected for the first time during pregnancy, it can cause developmental problems for the unborn child.
 

Genetic Carrier Screening

At Clinical Labs, we supply a comprehensive carrier screening service that is highly sensitive in identifying at-risk individuals and can be performed in a timely and cost-effective manner. These tests should be ordered for individuals or couples who are either planning a pregnancy or who are in the first stages of one, with or without a family history.

If there is a high risk of chromosomal or genetic disorders based on family history or ethnic background, RANZCOG recommend pre-conception genetic counselling for couples, with information provided to the couple about carrier screening.

  • Gene Access: A cystic fibrosis, fragile X syndrome and spinal muscular atrophy screening test. For more information, click here.
  • Comprehensive Carrier Screening: Screens up to 301 genes and is appropriate for patients of all ethnicities. The test evaluates an individual’s carrier status for more than 100 inherited diseases by analysing up to 400 genetic mutations. For more information, click here.
  • Ashkenazi Jewish Carrier Screening: Carrier screening for eight autosomal recessive conditions that are more common amongst the Ashkenazi Jewish community. For more information, click here.

References:

  1. RANZCOG Pre-pregnancy counselling. https://ranzcog.edu.au/RANZCOG_SITE/media/RANZCOG-MEDIA/Women%27s%20Health/Statement%20and%20guidelines/Clinical-Obstetrics/Pre-pregnancy-Counselling-(C-Obs-3a)-review-July-2017_1.pdf?ext=.pdf Accessed 30.10.2020 Accessed 30.10.2020