8TV – 不孕与助孕疗程
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.
Fight Oxidative Stress
The effects of alcohol, smoking and pollutants on women’s fertility
We all know that the excessive intake of alcohol, smoking and environmental pollutants are bad for our health, but can they negatively impact a woman’s chances of getting pregnant? The answer is a resounding (and unsurprising) yes! Here’s why – Firstly, as toxicants, they cause our bodies to produce Reactive Oxygen Species or ROS, which are highly-reactive ions and molecules that contain oxygen. ROS are a lot like free radicals, and they are both known to wreak havoc in our bodies by damaging proteins and impairing their function.
Usually, our bodies are able to neutralise the harmful effects of ROS and free radicals with antioxidants. However, when an imbalance in the production of ROS and free radicals occurs, our bodies are unable to cope. As a result, our bodies undergo what’s called – oxidative stress. Oxidative stress is a physiological condition that’s linked to a variety of health issues, including neurodegenerative disorders such as Alzheimer’s disease; cancer; heart problems; blood vessel, gut and vision disorders; lung conditions; chronic fatigue syndrome; kidney, autoimmune, arthritis and inflammatory disease; diabetes; pancreatitis and more.
There is also mounting evidence on the negative effects of oxidative stress on male subfertility, including decreased sperm motility and numbers. And now, findings indicate that oxidative stress can increase the risk for female infertility, as well as delaying pregnancies and lowering pregnancy rates. It can even lead to pregnancy complications like preeclampsia and even miscarriage.
While the field is currently understudied and there is so much more to discover, there is no denying that it is crucial for us to gain a better understanding of how to combat oxidative stress. “If we can identify factors that can be modified to decrease oxidative stress in women, it may be an inexpensive and non-invasive treatment for infertility,” states a study called The Impact of oxidative stress on female fertility by Elizabeth H. Ruder, Terryl J. Hartman, and Marlene B. Goldmanc.
But does this mean we have to play the waiting game for more research to be conducted on the subject? While it may be a few years time before scientists can identify the factors that can be modified to fight oxidative stress, there are steps you can take right now.
We know that oxidation occurs when we’re exposed to toxins, chemicals and stress. Therefore, it would be highly beneficial for you to minimise your exposure to triggers that are present in your lifestyle, foods and environment. Numerous studies have also shown the benefits of a healthy and varied diet, which is supplemented with multivitamins and antioxidants.
In addition, you can maintain your reproductive health by limiting caffeine and alcohol intake, quitting cigarettes, getting adequate exercise, learning ways to manage daily stress and maintaining a healthy body weight. By taking these steps and making crucial lifestyle changes, you can significantly enhance your fertility and boost your chances of conception. Not sure where to begin? Don’t hesitate to speak to a healthcare professional to get on the right track.
How a fathers’ lifestyle influences the health of future generations
We all know that a woman who is trying to conceive should eat a healthier and more nutritious diet. In addition, she should abstain from drugs, alcohol and cigarettes. This is because these factors can affect her chances of becoming pregnant, as well as have a negative effect on her developing fetus should she fall pregnant. Even a woman’ level of emotional stress could influence her fertility and pregnancy success. But does the same apply to men? How does a man’s lifestyle affect conception and the health of his offspring?
Unlike women, men’s reproductive health is under-emphasised and men are largely left out of pre-conception planning. This is despite the fact that male infertility is on the rise, with lower sperm counts and damaged sperm becoming more prevalent. Now, however, new studies are beginning to show that a father’s lifestyle can impact the possibility of pregnancy, as well as the long-term health of his children.
More than genes
Though the saying goes, “It’s all in genes,” scientists have discovered there’s more to our genetic inheritance than that. Beyond our DNA code is epigenetics, which can be defined as, “a heritable layer of biochemical information associated with DNA, and transmitted via the sperm and egg.”
According to Sarah Kimmins, PhD, who holds a Canada Research Chair in Epigenetics, Reproduction and Development and is an Associate Professor at McGill University, Montreal, “We are now beginning to understand that sperm epigenome contains a lifetime memory of paternal experiences. Everything is a man’s daily lifestyle, including his environment, diet, exercise, alcohol and smoking have the potential to disrupt (or support) the setting of the sperm epigenome, which is then passed on to future generations.”
Danger of chemicals
Besides lifestyle, says Kimmins, other factors that can contribute to male infertility are “Chronic conditions like obesity, cardiovascular disease and metabolic disorders, as well as paternal age and heightened stress.” Furthermore, the researchers at McGill University also believe that, “Reduced fertility may be in part attributable to the dramatic increases in chemical production and consequent human exposure.”
Their studies show that there are now about 80,000 chemicals registered for commercial use. We are exposed to these chemicals daily, be it at work, in household products, in the environment, as well as food and cosmetics. As an alarming result, high levels of common toxicants, like bisphenol A and phthalates can now be detected in urine and blood analysis of not just adults, but children too.
While only a handful of research groups worldwide are addressing the cause and effect of lifestyle and chemical exposure to human infertility and epigenetic inheritance, it is becoming increasingly that a father’s way of life plays a vital role in determining his child’s development and health. As such, Kimmins suggests that, “Men should become more involved in pre-conception planning and young men must be educated that their choices today may influence health beyond their own.”
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.
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.
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 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:
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.
The link between Vitamin D and fertility
Caucasian women love showing off a sun-kissed tan, so much so they would dedicate a good portion of their holidays to sunbathing. We Asian women, however, are the exact opposite, preferring to keep out of the sun, sometimes taking considerable pains to do so. This aversion to the sun is largely due to the desire to maintain a fair complexion, but is driven in part by concerns over harmful UV rays. This penchant for shunning the sun, however, has had an undesirable side effect on Asian women, as we are known to have lower levels of Vitamin D despite living in tropical climates.
Few people realise that vitamin D plays a significant role, not only in their general health, but their fertility as well. It has been shown that people living in countries with strong seasonal contrasts have always had fewer pregnancies during winter and more in summer, resulting in a baby boom around spring. Scientists have discovered that this ebb and flow has to do with exposure to the sun.
Over the years, this link between Vitamin D and fertility has been extensively investigated, but it has been further detailed in a systemic review published in 2012 by the European Journal of Endocrinology. The review, by Elisabeth Lerchbaum and Barbara Obermayer-Pietsch from the Medical University of Graz, Austria, assessed studies that evaluated the relationship between vitamin D and fertility in women and men, as well as in animals.
Here’s what the review, entitled ‘Vitamin D and fertility: a systematic review,’ found:
While the results are encouraging, the researchers emphasise that vitamin D supplementation alone can’t improve fertility issues. However, what is certain is that it is a safe and inexpensive treatment that can be a boon to conception. So if you’re trying to conceive, don’t shy away from the sun! Instead, aim to get about 15 minutes of sun each day and take care not to overexpose yourself to UV rays.
In my next post, I’ll be discussing another topic related to fertility and nutrition – the findings of the Dutch Famine Birth Cohort Study. Stay tuned!
The importance of micro-nutrients to conception
The adage goes, “You are what you eat,” and the same is true for fertility. But when you’re trying to conceive, you want to rely on much more than just an old saying. Statistics show that around 11% to 20% of couples experience subfertility. Of this, 10% can be classified as unexplained infertility, while 60% are classified as anovulatory subfertility. In my experience, couples today also find their infertility issues compounded by their hectic lifestyles.
Factors such as stress; unhealthy body weight; excessive smoking, alcohol and caffeine intake; exposure to toxins, as well as recreational drug use, can all play a role in affecting fertility. But even those who maintain a healthy weight, manage their stress and abstain from unhealthy habits may neglect a very important factor – nutrition. Fortunately, there is now hard evidence in the form of scientific proof that shows you can indeed improve your fertility by eating right, particularly by including micro-nutrients in your daily diet.
While macro-nutrients, like protein, unsaturated fats and carbohydrates can be easily obtained from the foods that you eat, micro-nutrients like vitamins, minerals and trace elements are often left out due to an unbalanced and unhealthy diet. Realising that micro-nutrient deficiencies are not uncommon in women of reproductive age, Dr Rina Agrawal, a consultant and associate professor in reproductive medicine and obstetrics/gynaecology at the University Hospital at Warwick University, conducted a study on the role of micro-nutrients in improving pregnancy rates.
The study, which involved 58 suitable candidates consisting of subfertile women with an average age of 32.3 years (range 19–40), investigated whether subfertile women undergoing ovulation induction using standard treatment regimens have higher pregnancy rates when given multiple micro-nutrient (MMN) nutritional supplements, as compared with folic acid alone. The findings of the pilot study unveiled that the women on MMN supplementation had a higher pregnancy rate of 66.7%, as compared with 39.3% for those on just folic acid.
This therefore suggests that additional MMN supplementations, such as vitamins B6, B12, folates, vitamin E, multivitamins, iron, zinc, copper and selenium, does improve female fertility. In addition to finding that the women on MMN supplementation had a higher chance of pregnancy compared to their peers, the women on MMN supplementation also required significantly fewer attempts to become pregnant, as compared with women on folic acid. But there are also other benefits to taking MMN supplements, including reduced reproductive risks ranging from infertility to miscarriage, and fetal structural defects to improved embryogenesis or placentation.
You may need only small amounts of micro-nutrients, but they are no doubt essential. Each vitamin and mineral plays a specific role in ensuring that your bodily systems function in top form, and needless to say they are vital to your overall wellbeing. In order to get more micro-nutrients from your daily diet, you should eat a wide variety of foods from the different food groups. It is also best to avoid eating fast foods and processed foods that are of low nutritional quality. Instead, opt for fresh fruits and vegetables, legumes, nuts and seeds, whole grains, lean meats, fish and low-fat dairy products.
Stay tuned to find out more about foods that can boost fertility.