A weighty issue


A weighty issue
How a woman’s weight impacts the risk of miscarriage

A miscarriage is a devastating experience for couples, perhaps even more so for those who have struggled with infertility and gone through the initial joy of a successful fertility treatment. Statistics have shown that in both natural and IVF conception, about one in six pregnancies will end in a miscarriage before the 20th week, with the rate being higher in older couples.

Understandably, couples are frightened of miscarriages and would rather not think or talk about it. However, it is important for couples to understand why miscarriages happen, as well as what they can do to reduce their risks.

Although the exact reason for a miscarriage is often unexplainable, it can occur due to a number of reasons. These include chromosomal abnormality, improper implantation of the egg and maternal health problems or trauma. The mother’s age also plays a significant role, as does her lifestyle, which includes exposure to stress, smoking, drug use, malnutrition, excessive caffeine, radiation and toxins.

Another well-studied factor than increases a woman’s risk for miscarriage, is her weight. As these studies indicate, if the mother is obese or underweight, this increases her risk of not only infertility, but miscarriage as well, regardless of the method of conception.


According to researchers at the Department of Obstetrics and Gynaecology, University of Adelaide, Australia, being overweight increase a woman’s risk of miscarriage by 29%, while being obese can increase the risk by 71% or more. However, for women undergoing assisted reproduction, researchers at the Assisted Fertilization Center, Brazil concluded that maternal obesity could increase the risk of miscarriage by up to 1330%.

Obesity also compounds miscarriage rates in women with PCOS. The Department of Obstetrics and Gynecology, Faculty of Medicine, Erciyes University, Turkey found that the miscarriage rate in obese women with PCOS is about nine times higher than average.

And while miscarriage is often the result of an unhealthy fetus, researchers from the Department of Obstetrics and Gynecology, Stanford Hospital and Clinics, CA, USA found that the risk of miscarriage of a healthy fetus is significantly higher in obese women (with BMIs of 25 or more).

While obesity has been identified as a risk factor for spontaneous miscarriage, the mechanism for it remains unclear. But a study by The Academic Unit of Reproductive and Developmental Medicine, The University of Sheffield and Sheffield Teaching Hospitals, Sheffield, UK points to the endocrinological changes in obesity as possibily causing complex adverse effects including circulating adipokines, sex steroids and insulin resistance.

Women who are underweight, with a BMI of under 20, also face an increased miscarriage risk. A study by researchers at the German Cancer Research Centre found that pregnant women who were underweight faced a 70 % higher risk of having a miscarriage.

Therefore, it can be concluded that among intrauterine environmental factors, nutrition appears to play the most critical role in influencing placental and fetal growth. Since maternal undernutrition or overnutrition during pregnancy can impair fetal growth, women must adopt healthier diets and incorporate exercise to lower their risk of miscarriage.

If you have any concerns regarding miscarriage, especially after IVF, please do not hesitate to consult with your fertility consultant for advice.


Nature or nurture?


Professor Watson & Crick, who unlocked the secret of DNA & Genes


A journalist who came to interview me a few years ago asked me a question: ‘What makes you become interested in reproductive science and inspired you to become a Fertility Specialist?’


I was quite taken aback by this question. I knew where this question was coming from: Being a daughter of a Professor in Chinese Literature, one who had thought that I would end up in field related to Sociology, Literature or Humanity. A doctor and a Fertility Specialist from such family, hmmm….an unlikely species.


I searched my mind long and hard, everyone who knew me knows that I have a passion for literature and social science. But why reproductive science? And why Fertility?

The answer became clear suddenly: I have the privilege to know a couple who was my parents’ neighbours and friends, whom I have have fondly called Uncle Chong Lek & Aunty Sam. This couple are both Professors in the field of Genetics. At the age of 9, I used to  listen to Uncle Chong Leh and Aunty Sam, who came to join us for a meal or a tea, and shared on their field of research and findings. I was fascinated and in awe, even at the tender age of 9.


Professor Koh Chong Lek & Professor Sam Choon Kook

How fascinating it is that we are governed by our genes which determined how we look like or  the colour of our skin? How did these DNA coding became the essential aspect of life forms ?

At that time, we have not discovered the secret of nurture versus nature in modifying our gene expression.

As I progressed in pursuing my acaedemic advancement, I find myself becoming more and more inclined to science related subjects. I was, genetically inclined to arts, but an exposure to this lovely couple had altered my genetic expression…..I became who I am, a doctor, then a Gynaecologist and then a Fertility Specialist, who works closely with scientists. Being involved in Fertility work, my practice is closely related to understanding of chromosomes and genes.


Nature or nurture?

An introduction to epigenetics

Many people believe that children are more the product of nurture than nature, meaning that the environment in which a child is brought up in has a greater effect on his or her well-being, personality and traits than the child’s genes. Yet, there are those who believe that a child’s inherent nature can’t be changed, despite the amount of nurturing received. Now, however, this debate has become academic, enter – epigenetics.

What is epigenetics?

Epigenetics is a new and complex science that looks at how lifestyle and environmental factors can affect a baby’s genes. In particular, it studies how the millions of markers in our genes can change our traits at a cellular and physiological level. Although the sequence of the genes we’re born with can’t be changed, it is believed that the way that they’re activated or expressed can be altered – for better or for worse. Furthermore, it is possible that these traits can then be passed down by an individual through the generations.

How it affects IVF patients

Most IVF patients who receive donated eggs and sperm feel that their baby won’t be taking much after them, as they don’t share the same DNA. However, according to epigenetics, this doesn’t have to be the case. In epigenetics, factors such as the uterine environment, stress levels and pregnancy diet can have a direct influence on the way that a baby’s genes are expressed. Therefore, in epigenetics, it is thought that IVF patients have a degree of control over how their egg/sperm-donor child might turn out, if they adopt healthy lifestyle choices.

But can the IVF procedure itself cause negative epigenetic consequences? According to a small Danish study conducted in 2010, it is possible. The study suggested that, “Babies born via assisted reproduction (i.e. IVF) had a slightly higher chance of getting childhood cancer.” As alarming as it sounds, the study was inconclusive and the risk appears to be minimal at best.

The importance of eating well

Through the decades, scientists have established a link between a healthy maternal diet and the well-being of babies. However, the effects can also be seen in reverse. For example, during the Dutch famine of 1944, thousands died of malnutrition due to Nazi blockades and a prolonged and harsh winter. The babies born during this period were not only underweight, but their genes were damaged.

Decades later, the Dutch Famine Birth Cohort Study would reveal that the offspring of children who were born during the famine were equally susceptible to being underweight and contracting illnesses like diabetes, obesity, cardiovascular disease and microalbuminuria. It is as if their genes had been ‘programmed’ with the adverse effects of malnutrition.


A greater power

Although epigenetics is yet to be scientifically proven, it certainly offers promise. True, it can’t be said for certain that the positive lifestyle changes you adopt before and during pregnancy can influence your baby’s genes. However, science notwithstanding, parents who have struggled to conceive possess a greater, innate power that rivals nature itself – love. And this love, coupled with positive thinking, has been known to conquer and surmount the greatest of odds.


Food for Pregnancy



Some of you may have known that one of my interest in the field of Fertility is the impact of Nutrition on Fertility & Pregnancy.

Some of the research work which I am involved in surrounds this unique aspect of Fertility.

Recently, I was invited to speak to a group of O& G and Paediatric doctors on this topic. The most interesting thing is that I was asked to speak on a platform erected on a beach and my dress code was white and a flower in my hair!!!! So, the picture above was definitely NOT a singing contest but a actual scientific lecture.

I had lots of fun researching for the talk and here is some of the interesting findings I wish to share about Nutrition and Pregnancy:

The Importance of Nutrition
Lessons from the Dutch Famine Birth Cohort Study

In this post, I’ll discuss another topic related to fertility and nutrition – the findings of the Dutch Famine Birth Cohort Study. Prior to the study, very little was known about the role and effects of a maternal diet on a baby’s health. However, using the medical records collected during the famine, scientists have been able to measure the adverse effects of fetal malnutrition.


Background of the Study

The Dutch famine of 1944, also known as “Hunger winter,” was a famine that took place in the Nazi-occupied part of the Netherlands. Affecting some 4.5 million people, the famine was caused by the shortage of food supplies in the Netherlands towards the end of World War II. Although the Allied Forces had liberated the south, their efforts to free the western parts of the Netherlands were repeatedly thwarted, worsening the situation.

This was followed by the Nazi embargo on all food transport to western Netherlands and the onset of an unusually early and harsh winter. During the period, which lasted until the Allies liberated the area in May 1945, rations were as low as 400-800 calories a day. This is less than a quarter of the recommended adult caloric intake. Though estimations vary, as many as 22,000 people are believed to have died due to the famine.


The findings

The Dutch Famine Birth Cohort Study was conducted by the departments of Clinical Epidemiology and Biostatistics, Gynecology and Obstetrics and Internal Medicine of the Academic Medical Centre in Amsterdam, in collaboration with the MRC Environmental Epidemiology Unit of the University of Southampton in Britain. They based their study on the antenatal and maternity records of babies born at the Wilhelmina Gasthuis in Amsterdam between November 1943 and February 1947. The first results of the study were published in 1976 and the study is still ongoing.

Here is a summary of some of their findings:

  1. The children of pregnant women exposed to famine were more susceptible to diabetes, obesity, cardiovascular disease, microalbuminuria and other health problems.
  2. The children were smaller and their children were also thought to also be smaller than average.
  3. Early gestation appeared to be the most vulnerable period.
  4. Children affected in the second trimester of their mother’s pregnancy had an increased incidence of schizophrenia and neurological defects.
  5. Famine exposure in utero causes transgenerational effects.
  6. The effects of famine varied according to its timing during gestation, especially during critical periods of organ and tissue development.
  7. Undernutrition during any period of gestation is associated with reduced glucose tolerance and raised insulin concentrations at age 50 and 58.
  8. People exposed to famine in mid gestation had an increased prevalence of obstructive airways disease.

The most well-known survivor of the Dutch famine is perhaps Audrey Hepburn. Often admired for her gamine figure, Hepburn spent her childhood in the Netherlands during the famine. Throughout her life, she suffered from a series of health problems, including anemia, respiratory illnesses, edema and clinical depression, which were attributed to the malnutrition suffered in her early years.



The Dutch famine study has shown us that poor maternal nutrition during gestation can have detrimental effects on the health of children and even subsequent generations. Therefore, we cannot ignore the importance of maternal nutrition during pregnancy, especially in preventing chronic degenerative diseases in future generations. We must also be wary of the possible detrimental consequences of undernourishment in mothers due to unbalanced diets, rigorous fasting and severe morning sickness, especially during the first trimester.