Medical And Mental Health Issues
An assessment of any medical problems and a discussion of how they may affect, or be affected by, a pregnancy should be undertaken. Stabilisation of pre-existing medical conditions and assessment of mental health status prior to a pregnancy is necessary to optimise pregnancy outcomes.
Medication use
It is important to review all current medications including over the counter medicines, with regard to their appropriateness and teratogenic (birth defect) potential l. Consideration may need to be given to changing medication prior to a pregnancy with a view to achieving the dual objectives of optimising disease control while minimising teratogenic risk.
Vaccinations
Vaccination history for SARSCoV-2, measles, mumps, rubella, varicella zoster, diphtheria, tetanus and pertussis should be checked and maintained as per recommendations published by the relevant Australian and New Zealand Government bodies.
Hepatitis B, rubella and varicella immunisation should be considered for women with incomplete immunity.
Lifestyle recommendations
Healthy weight Active steps to correct high BMI (dietary, exercise and where appropriate consideration of bariatric surgery) prior to a pregnancy should be recommended.
A healthy, well balanced diet is strongly recommended before, during and after pregnancy. Discussion regarding weight management is appropriate with counselling against being over or underweight.
High BMI (>30) is now one of the commonest and most important risk factors for infertility and adverse pregnancy outcomes. Such risks can manifest even before conception and implantation.
High BMI has been shown to affect the health of the human oocyte and the quality of the early embryo. High BMI has an adverse impact on the rates of miscarriage, stillbirth and fetal abnormality. Further, a high BMI exposes the mother to an increased risk of many pregnancy and anaesthetic complications. There is also increasing recognition of the intergenerational effects of maternal obesity that may manifest during childhood with obesity and/or later on in adult life with increased risk of metabolic disease.
Active steps to correct obesity (dietary, exercise and where appropriate consideration of bariatric surgery) prior to a pregnancy are worthwhile. A recommendation for moderate intensity exercise and assessment of any nutritional deficiencies is appropriate. Excessive caffeine consumption (>300mg/day; equivalent to 3-4 cups of brewed coffee/day) should be avoided.
Supplementation
Folic acid should be taken for a minimum of one month before conception and for the first 3 months of pregnancy.
The recommended dose is at least 0.4mg (400 micrograms) daily, which is in the common preconception supplements.
Where there is an increased risk of NTD (Neural tube defect) such as anti-convulsant medication, pre-pregnancy diabetes mellitus, previous child or family history of NTD, or a BMI >30 then a 5mg daily dose should be used.
Substance use
Counselling and pharmacotherapy should be considered for either or both parents when relevant. Advice to women that there is no known safe level of alcohol consumption during pregnancy is appropriate.
Reproductive carrier screening
All women and couples planning pregnancy should be offered reproductive carrier screening. This is a complex area to understand.
For detailed explanations see Australian Clinical Labs, Sonic Genetics Site, RANZCOG, and NSW Health.
If there is an increased risk of a heritable disorder, based on the family history or ethnic background, then pre-pregnancy genetic counselling should be offered to assist in determining the couple’s risk of an affected child and to provide information about options for carrier screening, preimplantation genetic diagnosis, prenatal diagnosis and postnatal management.
Why test for these conditions? We all have two copies of most chromosomes, and each parent passes one copy of each chromosome to their child. The chromosomes are made of DNA, the chemical that encodes the genes in every cell of your body.
In the past, the only clue that a healthy person was a carrier had been the diagnosis of a genetic condition in their child. That has now changed. We can examine the genes of a couple to see if they are a carrier and at increased risk of having an affected child before a woman becomes pregnant (preconception) or in early pregnancy.
If a couple is shown to be at increased risk of having an affected child, they can make an informed choice to accept that risk or consider a range of reproductive options such as IVF and prenatal testing to reduce that risk.
What is a carrier? A carrier is a person who has a genetic change, or mutation, in their DNA, but in most cases does not have any associated health problems. Carriers are, however, able to pass that mutation on to their children, who may then develop a genetic condition.
Carriers are usually not affected. The presence of one normal copy of the gene is sufficient to keep a carrier healthy. However, some women who are carriers of an X-linked condition can show signs of the condition, despite having a second normal X chromosome.
What are examples of the carrier screening tests available? There is a 3 Gene test (~$385 per person, but may be less if eligible for a medicare rebate). This tests for carriers of the following mutations; Cystic fibrosis (CF) | Spinal muscular atrophy (SMA) | Fragile X syndrome (FXS)
There are medicare rebates for fragile X (item 73300) and cystic fibrosis (item 73348) carrier testing, with each having restrictions on availability.
Apart from the three gene test, there are also expanded carrier screens available (~$600 per person): For example, the Beacon screen. The Beacon expanded reproductive carrier screen tests more than 400 genes to identify if you are a carrier of a genetic condition that could affect your baby. This comprehensive screen can detect one in 20 couples at high risk of having an affected child.
The decision to have any testing is entirely your choice. If testing takes place, it is usual to test the mother first, and only offer testing the partner if the mother is shown to be a carrier.
