Discovering a defect

After a traumatic ectopic pregnancy and IVF, it was almost unreal when we found out we were having a baby. Despite my fertility battles with polycystic ovarian syndrome and endometriosis, I was only 31 and anticipated an easy and healthy pregnancy. And apart from morning sickness, I sailed through my first trimester.

Then we had the 22-week scan. For half an hour, my doctor methodically checked my baby's head, her spine and organs, nodding reassuringly as she explained what she was measuring. And then she got to the feet and said, “Oh, that's not good.” We saw her feet. Her tiny little deformed feet. Her tiny little clubbed feet. And my world fell apart. She explained that club feet can be formed by the way the baby is lying or can be linked to a congenital condition. "Sometimes the brain just forgets to turn the feet out," she said calmly.

After a second scan confirmed the diagnosis, our doctor explained what we were up against. She told us that there was a 10 per cent chance that clubfeet had something more sinister linked to it. They can be linked to chromosomal abnormalities, specifically chromosome 18 abnormalities. A lethal defect, our baby would die shortly after birth. Or it could be nothing – just nature’s cruel way of providing me with a child who is special. And, in time, her feet would be fine and she’d walk and run just like any other kid.

Before we fell pregnant, we had agreed that we would terminate if our child was mentally handicapped or had Down’s syndrome. But we never thought we would have to face that in reality. The legal termination date in South Africa is 24 weeks and, at 22 weeks already, our options were limited. Amnio results would take a couple of weeks and by then it would be too late to terminate. Or we could leave it and take our chances. Our only other choice was cordiocentesis – a test that would give us rapid results, but carried a worrying risk of miscarriage. How do you make a decision that could potentially kill your unborn child, especially one you can feel wiggle and tickle you from the inside out?

Armed with case studies and information, we went home to weigh up our options. We took turns crying as we hashed it out, but we both knew we couldn’t endure the rest of the pregnancy not knowing if our baby would survive into childhood. If there was something wrong, we wanted to know what it was. Knowing that you might lose a perfectly healthy baby because you have had a test is terrifying, but having a mentally handicapped baby scared me more.

Two days later we returned to the clinic. I thought I had got used to needles and being prodded and poked from the IVF but I was terrified. You need to be very still when you have cordiocentesis. I was anxious, tearful and jittery. Our doctor put on two pairs of gloves, cleaned my stomach and asked me to look at the screen so I could see what she was doing. If I had moved as the needle went in, it could have caused problems.

She put the ultrasound on my tummy to locate my placenta. I was looking at my baby wiggling and I just couldn’t bare to lose her. I mentally urged her to keep still. A needle was inserted just above my belly button. It took about five attempts to get the needle into the umbilical cord to draw some of baby’s blood. The only way I can describe it is that it hurt like hell; almost like when you have a blood test by an inexperienced nurse who has to dig around to find a vein. With each attempt, my fears that I would lose my baby increased. Finally they retrieved enough blood from the umbilical cord.

The next 48 hours were crucial, but the risk of miscarriage only really passed after two weeks. I had to keep as still as possible for the next two days. I watched the entire first season of Lost and got up only to go to the toilet. Each time I sneezed, I cringed.

A week later we got the results. Her tiny feet would be a stumbling block at her birth, but otherwise she was healthy. Then came the “what can we do about it”? Months of casts, surgery, physiotherapy. My poor little girl. How would I breastfeed when both her legs were in casts? How would we bond? How much pain would she be in while they contort her feet to the correct angles? The next two months were a waiting game. We painted the baby room, chose a cot and names and got excited.

It’s going to be hard to have a new baby. It’s going to especially hard to have a baby that needs extra care. Our baby's is being watched closely, just to make sure that she continues to grow and develop. I lie on the couch at night feeling her wiggle and squirm and kick. And having clubfeet does not stop her kicking with all her might.

The blood tests

Antenatal tests (meaning ‘before birth’) are designed to offer reassurance that your baby is healthy and growing well. They also determine if your baby has any congenital abnormalities or a genetic condition. Diagnostic tests confirm whether the baby has a chromosomal abnormality while screening tests assess the risks of the baby having a condition.

Pregnancy test

When 6 to 10 weeks

What are they screening for? To confirm pregnancy and screen for HIV and other conditions that could affect the baby (eg immunity to German Measles, your blood type and anaemia). You may also be required to do a urine and test and pap smear by your doctor

How long do the results take? One to two days

Triple test

When 15 to 18 weeks

What are they screening for? Blood is screened for other markers not picked up by ultrasound that could indicate congenital or genetic conditions by checking the levels of alpha-fetoprotein (AFP), beta human chorionic gonadotropin (beta-hCG), and a type of estrogen (estriol).

These levels, along with the mother’s age and the results of an ultrasound, are used to determine the risk of the baby having < a href=http://www.fitpregnancy.co.za/your_baby/development/171/>birth defects. High levels of AFP may suggest that the developing baby has a neural-tube defect such as spina bifida, anencephaly and other defects.

Low levels of AFP along with high levels of hcG and low levels of estriol are a marker for Down’s syndrome and other conditions.

How long do the results take? A day or two

What next if the results are bad? The mother will be referred for genetic counselling and an anomaly scan (see ultrasounds). If the ultrasound is normal and amniocentesis is also normal, foetal growth in the third trimester will be carefully monitored as abnormal levels of these hormones can be associated with IUGR, pre-eclampsia and increased perinatal mortality in the third trimester.

NOTE: This test alone will only pick up 60 per cent of babies with Down’s syndrome and up to 90 per cent of babies with neural-tube defects. It has a false positive sensitivity of five per cent. Approximately two in 50 women with an initial high reading will have an affected foetus.

What the experts say “This test is not compulsory and should be reserved for patients who have missed their nuchal-fold translucency scan, but want to be screened for Down’s syndrome. If your doctor is not accredited to do the nuchal translucency risk assessment scan for Down’s syndrome, and you don’t have have access to a foetal assessment centre, ask for a triple test to make sure,” recommends Dr Shannon Morris, a sonologist at The Kingsbury Fetal Assessment Centre in Cape Town.

NEED TO KNOW: There are no side-effects and risks from blood tests. However, a false-positive test could lead to more invasive tests that do carry risks.

Ultrasound tests

The 13-14 week scan (including nuchal translucency)

What are they diagnosing and screening? This scan confirms a heartbeat, that the foetus is a singleton (not twins) and is developing in the uterus, although often this is done at a six to eight-week scan if requested by the patient or recommended by your doctor. The heart rate is measured and early developmental anatomy is checked, as is the volume of amniotic fluid and the condition and position of the placenta.

“We can pick up large, open spina bifida at this stage and determine if the baby’s gut is developing on the inside,” says Dr Morris.

Risk levels A nuchal-translucency measurement is done to assess the risk of Down’s syndrome. “Eighty to 90 per cent of affected babies have a thick neck and flat face. We also look at the nose bone, which normally develops at 11 weeks, but is only seen in Down’s syndrome babies at 14 weeks in most cases. These markers, along with increased fluid at the neck, increase our pick-up rate for this condition,” says Dr Morris. A thick translucency measurement can also be a marker for other disorders.

How long do the results take? The results are immediate and your risk assessment will be calculated and discussed with you by your doctor.

What next if the results are bad? The results of the scan and a double blood test (see blood tests), along with the mother’s age, calculate the risk of Down’s syndrome. If your risk profile is high you may be offered an invasive test. You will be counselled on the risk of having an abnormal baby and further diagnostic testing (see CVS) may be recommended.

What the experts say “If 100 women were pregnant with Down’s syndrome babies, this scan would pick up 80 while the blood test would pick up a further 15 out of the remaining 20,” says Dr Morris.


The foetal anomaly scan

When 20-23 weeks

What are they diagnosing and screening? “You have to recheck the baby’s growth at this stage to look at anatomy that isn’t visible at 13 weeks due to foetal size. This screening scan, called the foetal anomaly scan, includes checking the baby’s growth and looking at its anatomy, heart and brain development,” says Dr Morris. “It can also pick up other soft markers for Down’s syndrome (fluid on the kidney, short limbs) and can diagnose spina bifida and a cleft lip.” The mother’s placenta is also checked to ensure there are no problems with blood flow to the baby.
How long do results take? Your doctor will convey any concerns once the scan has been performed. It usually takes about 30 to 45 minutes depending on what position the foetus is lying. This affects how well the scan can be performed.

Risk levels “At this scan the most common abnormal diagnosis is a heart defect. Major cardiac anomalies account for 50 per cent of all childhood deaths. “Three to eight out of 1 000 live births have heart defects. About one to four are serious enough to require surgery,” says Dr Morris.

What next if the results are bad? Depending on the severity of abnormalities, termination is an option. You will be referred to a geneticist or other specialist for counselling to assess the outcomes if you proceed with the pregnancy and to assist you with this decision.

“We usually refer the patient to a specialist such as a plastic surgeon if the baby has a cleft palette or a cardiologist if there is a heart defect to be counselled on their options. It’s important to prepare them for all possible outcomes and to ensure that the right specialists are at the delivery,” says Dr Morris.

If the results put the mother at risk of preterm labour, steroids would be administered to prepare the baby’s lungs for birth.

NEED TO KNOW: While it’s lovely to have regular ultrasound photos of your baby to send to the grandparents and pin on your fridge, most medical aids with comprehensive plans will only pay for two. Check with yours before you start building your picture gallery.

Invasive tests

These are diagnostic tests that will be offered if screening blood tests or scans have picked up problems, if you have had babies with chromosomal abnormalities before or if parents request invasive testing for maternal age. They are used to confirm chromosomal or genetic defects.

These scans are not compulsory and you will be offered one of the following:

Chorionic Villus sampling (CVS)

This diagnostic test confirms genetic and chromosomal abnormalities. It is offered at 11 to 15 weeks. Full culture results take 14 days, while the rapid test (chromosomal count only for chromosomes 13, 18, 21 and the sex chromosomes (known as PCR), takes 36 to 48 hours.

How it is done? An ultrasound confirms the position of the baby so it is not harmed. A local anaesthetic is administered and a very fine needle is inserted into your abdomen so that a small piece of the placental tissue can be removed for testing. This can also be performed vaginally.

How long do results take? 14 days for a full culture. A rapid three-day test will pick up the most common disorders by doing a chromosome count.

What the experts say “Because this test is done during the first trimester, and the results are available quickly, if the patient chooses termination, it is early in the pregnancy and it can make the decision to terminate less traumatic,” says Dr Morris.


Amniocentesis

This diagnostic test is offered between 15 and 20 weeks to women whose previous tests, or their age or previous history, categorise them as high risk.

How it is done? A very fine needle is inserted through your abdomen into your uterus so that a small amount of amniotic fluid (which contains DNA cells shed by your baby) can be removed for testing.

How long do results take? Three weeks for the full culture and 24 to 48 hours for PCR.

What the experts say “I recommend that an amnio be only performed from 15 weeks. There is some evidence to show that performing it at 12 or 13 weeks can increase the risk of the foetus developing clubfeet and has a higher risk for miscarriage than CVS. A CVS is recommended if an earlier invasive test is required.”


Cordocentesis

This diagnostic test is offered between 21 and 23 weeks and is usually reserved for people who have had no early screening tests or for patients who need foetal blood sampling for suspected foetal anaemia.

How is it done? A hollow needle is inserted into the umbilical cord to collect a small amount of blood from the baby. It enables your baby’s blood to be examined. It also tests for chromosomal and genetic disorders. Results are usually available within five to seven days.

What happens if the results are bad? You will be offered counselling to decide on termination or on the possible outcomes if you decide to proceed with the pregnancy.


RISKS OF INVASIVE TESTS

While the risk of miscarriage with CVS is higher than amniocentesis (one to two per cent versus one per cent), this must be weighed against that fact that it is done during the first trimester when spontaneous abortion risk is higher anyway.

If you adjust for the spontaneous loss rate, then CVS is as safe as amniocentesis in experienced hands. “At our clinic we have a 1 in 300 loss rate,” says Dr Morris. “Ask for your clinic’s personal loss rate as it should be low if performed by experienced professionals.”

Age Risk

“At the age of 35 your risk of having a baby with Down’s syndrome and chromosome disorders increases because the quality of your eggs decline at this age. The risk factor increases further as you hit 40.

However, a healthy 35-year-old is less at risk than an unhealthy woman of this age,” says Dr Morris. “Twenty eight per cent of women we see in our practice are over 35. Because more older women are having babies there are more women who are at risk.

That is why we encourage first-trimester screening tests for Down’s syndrome to get them to move away from only considering their age and look at the combined risk factors to be able to make a balanced risk analysis.”