Imagine being a doctor and having to treat patients you can’t see. Nor can you ask them how they are feeling, or whether they have noticed particular symptoms. That’s the challenge presented by a foetus developing in his or her mother’s womb. But over recent decades ultrasound has provided an invaluable window into pregnancy to check that all is well. A nd if all is not well, the approach can pick up hard-to-diagnose conditions like heart anomalies and blood disorders in the womb, enabling life-saving treatments in some cases.
“Ultrasound can tell us a lot about the foetus that we wouldn’t otherwise know,” says Professor Fionnuala McAuliffe, consultant obstetrician and gynaecologist and maternal and foetal medicine specialist at the National Maternity Hospital in Holles Street and associate professor in obstetrics and gynaecology at UCD School of Medicine & Medical Science.
“Ultrasound allows us to assess the foetus — we can look at foetal wellbeing and foetal structure, see are they developing normally, are they moving and breathing, and measure bloodflow.”
The technology forms an integral part of Professor McAuliffe’s clinical and academic work, which includes monitoring special situations such as twin pregnancies or pregnancies where the mother has a condition like diabetes or hepatitis C, and more generally, even looking at how a mother’s diet can impact her baby long after birth.
Professor McAuliffe was drawn to the challenges and rewards of obstetrics while studying medicine at UCD before building up her expertise in Toronto and the UK and then returning to Dublin.
“It is a fascinating specialty, it’s very challenging — it covers medicine and surgery and it can be very exciting when things happen on the labour ward,” she says. “Also, these are young women at a very happy time in their lives, so that makes for a very nice atmosphere in the hospital.”
But while pregnancy is often a happy time, problems can arise. A nd if they do, ultrasound has given medical staff new ways of detecting and addressing some of those threats, including anaemia, or low iron levels in the blood.
“Some babies are anaemic in the womb and the only way you can detect this it is by ultrasound to look at the blood flow in the brain. An anaemic foetus will send whatever oxygenated blood they have up to the brain because the brain is an
essential organ, so if the blood flow in the brain is increased it’s quite a sensitive marker for anaemia. If we don’t manage those cases properly those babies would die,” says Professor McAuliffe. “And if one looks at the annual reports
from the 1950s, 60s and 70s there were a lot of foetal deaths from rhesus disease where the mothers are rhesus positive, but now we can monitor those pregnancies and carry out blood transfusions — at the NMH we do about 30 to 40 transfusions per year.”
Blood flow problems can also arise in twin pregnancies, where one twin gets the lion’s share of blood supply. In severe cases, the other twin could die without intervention.
Careful monitoring with ultrasound can diagnose the problem, then doctors can perform surgery in utero to fix the communicating blood vessels, explains Professor M cAuliffe.
In some cases the mother has a pre-existing condition that could be passed on to or otherwise affect the baby. For pregnant mothers with hepatitis C, efforts have been focussed on managing delivery to help minimise the risk of ‘vertical’ transmission of the virus from mother to child.
A five-year study of mothers at the Rotunda and NMH by Professor M cAuliffe and her team showed that managing such deliveries with a planned Caesarean section did not affect the risk of the virus from mother to child. “Some centres internationally have been doing C-sections for these women but our study showed that C-section doesn’t have an impact in vertical transmission,” says Professor McAuliffe.
The finding has already informed practices at the Dublin hospitals for managing delivery in Hep C pregnancies, and the study is also exciting international interest, says Professor McAuliffe: “We are not doing C -sections now as a result and I think it saves a lot of ladies unnecessary sections.”
Diabetes too can pose potential challenges for pregnancy, and professor M cAuliffe has been monitoring foetal development in mothers with Type I diabetes.
The work has highlighted the impact of poorly controlled sugar levels in pregnancy on the structure and function of the foetal heart. “We found that even at 14 weeks [into pregnancy] there were differences in the foetal hearts in the women with Type I diabetes — that was quite surprising and we were the first people to show that,” says professor McAuliffe.
“Then later in the pregnancy there were definite changes in the heart and the higher the sugars were the more marked the changes were.” Her more recent work has consolidated the stuctural findings, showing that the foetal heart can also be under physiological stress in poorly controlled type I diabetic pregnancies.
And while the majority of the babies in these studies were clinically well, the findings could help shed light on why the babies of diabetic mothers tend to have somewhat increased risks of obesity, cardiovascular disease and diabetes later in life, she explains.
The long-term impact of the prenatal environment is also the focus of another study to which Professor McAuliffe is contributing: a H ealth R esearch Boardfunded trial to examine the effects of maternal diet on a child’s appetite and weight after birth.
The study is tracking and comparing pregnancies where mothers are on a typical ‘Western’ diet and mothers on a diet rich in wholegrains.
“After you eat high glycaemic index foods like white bread and potatoes there’s a rapid rise in sugars in the bloodstream and that will cross directly over to the foetus and could stimulate foetal growth,” says Professor M cAuliffe. “If one ingests brown bread and wholegrains there won’t be such a rise in sugar and the foetus won’t be exposed to that sugar.”
The ongoing trial of around 700 women is monitoring foetal, baby and toddler growth and relating it back to diet in pregnancy, she explains.
“We are in the middle of an obesity crisis where one in four of our nine-year-olds are obese and if some of that is due to mothers eating high sugar foods in pregnancy then perhaps a simple intervention by changing to brown bread and whole grains,” she says.
“From a public health policy it can be very rewarding to intervene in pregnancy, so if for instancemoney was put into promoting maternal health and good maternal nutrition, that could reap benefits for 30 or 40 years down the road in terms of cardiovascular disease and diabetes. I think that looking at this area could have a big impact down the road.”
Perinatal Ireland
Around one in every 50 pregnant mothers in Ireland gets some special news: that she is carrying not one baby but two.
Twin pregnancies can deliver double the joy, but they need to be carefully monitored to ensure both foetuses are doing well in utero.
And now the largest study of its kind in Ireland has collected data on around 1,000 twin pregnancies here to help inform clinical practice.
The aim is to better understand how twins grow in pregnancy, explains Professor Fionnuala M cAuliffe, a principal investigator in the Perinatal Ireland consortium that links six academic centres north and south and covers around 40,000 births each year.
The approach is building up a wealth of clinical data that can form the basis of research, and a new study to start in 2010 will examine growth restriction to see how outcome can be improved, says Professor McAuliffe, who is a investigator for UCD and the National Maternity Hospital in the consortium.