There are multiple causes for fetal anomalies.
There are measures that we can take to reduce the frequency of fetal anomalies.
Tests are available to assess if the fetus is normal. When an anomaly is found a team of specialists will be required in further management.
Patients need to be well informed about the significance of the anomaly and the potential impact on their child’s life.
Fetal abnormalities may occur randomly but others are the result of causes such as:
- Nutritional deficiencies.
- Intra uterine infections.
- Exposure to toxins.
50% of congenital defects have no identifiable cause. Sometimes they may not be detected until birth or later in life.
Pre pregnancy counselling
Pre pregnancy counselling is always a great idea! Patients need to be informed about ways of minimising the chances of having a baby with an anomaly.
A comprehensive family history needs to be taken to try and identify anomalies that may have affected other family members in the past.
If certain abnormalities are identified in the family history it may be possible to screen for these conditions to try and calculate a recurrence risk.
There are now a number of screening tests available for inherited conditions.
Existing medical problems
Women with pre-existing medical problems need to have their condition well controlled before pregnancy. Medications that they are taking should be modified, reduced or ceased if there is any chance that these medications may affect fetal development.
Before conceiving it is important to undergo relevant vaccinations against viruses that can impact on fetal development such as Varicella, Rubella & Measles.
Nutrition and Vitamin Deficiencies
It is always a great idea to watch your weight, keep fit and commence pregnancy specific vitamin supplements.
Neural Tube Defects and deficiency of folate is one good example of the link between vitamin deficiency and fetal anomalies.
Changing life style
Some fetal anomalies can be caused by exposure to teratogens or toxins.
It is important to stop smoking, stop alcohol intake and stop taking any recreational drugs.
Life style changes are particularly important.
These recommendations are very important steps to reducing certain types of fetal anomaly.
Antenatal anomaly screening of all patients
All pregnant patients should be screened for fetal anomalies.
It is essential that all patients must be offered the options of screening for inherited disorders and for chromosome and structural anomalies.
Testing for inherited disorders
Ideally it is better that prenatal testing is performed for couples that have a risk of having a baby with an inherited disorder.
Some couples that have already had a previous pregnancy with an inherited anomaly might consider the option of an IVF pregnancy with pre genetic testing (PGD) before implantation. This would avoid the potential consideration of termination of any naturally conceived affected pregnancy.
Once pregnant a couple that have a high risk of an inherited disorder will need diagnostic testing. An amniocentesis or CVS would be required.
Tests for chromosome anomalies
Screening tests – Combined first trimester screen or NIPS test.
Diagnostic tests – Amniocentesis or C.V.S. with micro array.
Diagnostic tests do carry a small risk of miscarriage. It is wise to discuss the balance of risks with your obstetrician.
Tests for structural abnormalities
All patients should have high quality ultrasound scans to identify structural anomalies. Not all physical abnormalities can be identified but high quality scans can see most major anatomic anomalies.
Patients need to be well informed
Certain fetal abnormalities may be random and isolated structural defects.
Other congenital defects can be part of a syndrome where multiple anomalies occur together. They may have a genetic cause and they may have other long-term sequelae.
Patients need to know if any treatment options for the baby are potentially available. To obtain this information we would always seek the advice of geneticists, paediatricians and paediatric surgeons.
It is a difficult time for a couple to consider the consequences of an identified fetal anomaly and what their options might be and counselling is essential.
They will need a lot of support and must be well informed so they can make correct decisions.
Some couples will benefit from contacting various existing associations, which exist for various childhood conditions.
Do not be fearful because serious congenital abnormalities are not common.
- Lead a healthy life.
- Take your vitamins.
- Don't smoke and don't drink alcohol.
- Consult your Physician regarding the use of high-risk medical drugs.
- Do not take any recreational drugs.