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The Fibromyalgic Pregnancy and Beyond - Tips to help you navigate the screening and diagnostic odyssey

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Category: Information Booklets

Published on Saturday, 27 August 2011 14:52

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Tips to help you navigate the screening and diagnostic odyssey

Is my baby (foetus) okay?

This question is likely to cross every expectant parent’s mind at least once during the pregnancy. For those with pre–existing medical conditions this worry can be magnified out of all proportion. There are many reassurances that pregnancy screening and diagnostic testing can provide. However there occasionally are also some questions that can never be completely answered until after your baby is born. These tests described should be offered to you and your partner as an option, for it is your choice whether you have them.

Screening options

These will give you a risk result reflecting the likelihood of your baby having certain disorders.  They are usually in the form of a scan or blood test and do not directly carry a risk to your baby’s health.

 Ultrasound screening

An ultrasound in early pregnancy can verify your due date and determine whether or not you are carrying multiple babies. Unlike x-rays, ultrasound uses sound waves to produce a video “picture” of the foetus moving inside your uterus. This picture is generated from an instrument, called a probe that is placed either on your abdomen or in your vagina. Some people with FM complain that they find the ultrasound waves from the probes irritating as they pass through the skin, describing the sensation as a painless but irritating electric current.

The good news is that you can watch your baby on the screen while the scan is being done and this should be a pleasant distraction. Some women with FM may find the full bladder required for a good scan at this stage of pregnancy almost excruciatingly painful. Make sure the person doing your scan is aware you suffer from FM and if necessary explain the problems a prolonged period of time with a full bladder may cause. When you empty your bladder after the scan, the sudden release of fluid from your tense muscles may cause you to feel quite faint so it would be sensible to ask your partner to come in the toilet with you. This is not unique to FM sufferers but seems to be much more common in people with FM and connective tissue disorders. The hospital should have a toilet cubicle able to accommodate you both.

 Ultrasound can be used to detect a problem or monitor a condition in the foetus during pregnancy. From week 11 to week 13 and 6 days, a nuchal translucency scan can be done to check for risk of chromosomal abnormalities such as Down’s, Edwards and Patau’s syndromes and is often combined with blood tests taken just before the scan; your overall risk will be calculated from the results of both the scan and the blood tests (see first trimester combined screening below). This is not a diagnostic test giving a yes or no answer; this is a form of screening which gives you a risk factor for these disorders.  If you are considered to be at increased risk then an appointment will be made for you to discuss what options are available to you, including diagnostic testing.

 If you are six or more months pregnant and the baby is positioned correctly, a scan should be able to determine foetal gender, although some hospitals have a policy of not reporting on this, so you may need to pay privately to find out your baby’s sex. Later in pregnancy, a scan can track the baby’s growth, locate the placenta, determine the volume of amniotic fluid and detect some types of birth defects such as ones involving the heart valves or kidneys. A full bladder is not required for scan at this stage so you may find these scans quite enjoyable except for the electric “zapping”.

First trimester combined screening

Three or four hormone levels (the number varies between hospitals) are measured in your blood and the results are combined with information on your age, weight and stage of pregnancy.  A computer programme then works out the risk of your baby having Down’s syndrome, Patau’s syndrome, Edward’s syndrome or Spina bifida.  The results are obtained from a blood sample from the mother normally around 16 weeks pregnant but can be done anytime during 15 weeks to 20 weeks and 5 days. It is offered to all pregnant women who have not had a nuchal scan.

It is not uncommon for people with FM to find their arm aches at the site where the needle was inserted for 24 hours or so after the blood test so it may be wise to ask if you can have all your routine pregnancy bloods done at the same time. The majority of neural tube defects and a high proportion of babies with Down's Syndrome can be detected with this test. Further testing such as ultrasound and/or amniocentesis may be required with an abnormal test. The Spina bifida part of this test (AFP) can still be done even if you have had a nuchal scan (or if you do not wish to know your risk of having a baby with Down’s syndrome), but you will not be offered the Down’s syndrome screening part of this test if you had a nuchal scan, as you will have been given a risk result for Down’s syndrome when you had the nuchal.

Alpha-Fetoprotein Test (AFP)

This blood test is still offered in some maternity hospitals though many now offer 18 -20 week detailed scanning instead.  The AFP test is performed between the 15th and 20th weeks of pregnancy and is used to help detect neural tube defects. Neural tube defects are abnormalities in the brain and spinal cord of the foetus. Defects in the central nervous system occur when the neural tube (the brain and spinal cord tissues) fail to close as the foetus develops. When the brain and spinal cord are exposed directly to the amniotic fluid which surrounds the baby, it is called an “open defect.” Sometimes, the poorly developed neural tube is covered by skin or bone, referred to as a “closed defect.”

The two common neural tube defects are anencephaly and Spina bifida. Babies with anencephaly are born with deformities of the head and brain and die soon after birth. Those born with spina bifida can live a long time, but may suffer paralysis in the lower body and legs. Often, there is also a lack of bladder and/or bowel control which may be treated with surgery. The chance of producing a child with a neural tube defect is one to two for every thousand live births. Babies born to mothers who have had a previous child with the same problem are at greatest risk, as are those with parents or grandparents who have neural tube defects.

As with all antenatal screening tests, a low risk test result does not guarantee a normal baby at birth. About 20 percent of the infants born with neural tube defects have normal alpha-fetoprotein (AFP) levels. Most of these are closed defects which are typically less severe. Conversely, an initial abnormal test reading does not mean the foetus has a neural tube defect. Abnormal levels of AFP are frequent - occurring in about 50 of every 1,000 women tested. Only one or two of those 50 actually have a neural tube problem. A high AFP may be due to a miscalculation of the baby’s age, or if you are pregnant with twins!