Genetics affect who you will grow to be in many ways. Deoxyribonucleic acid (DNA) is the language of life that is within every living thing, genetic instructions that form what we will become. There is still much of the language that scientists don’t understand, but after extensive research scientists have found that certain gene codes actually relate to increased chances of developing a cancer or disease. We only have to look at family medical histories to know that is true, some diseases are clearly more common in families than in unrelated people. But whether a genetic predisposition actually makes a person ill depends on the interaction between genes and the environment. For example you are much more likely to develop lung cancer within your lifetime if your parents/grandparents have had it; it is likely that you have been handed down a gene that increases your risk of developing it. However if you smoke regularly and do little exercise then you are putting yourself at an increased risk of developing it sooner and more rapidly. Genetics also affect our appearances, body shape and how tall we can become. Half our chromosomes come from our mother and the other from our father.
Our appearances tend to more or less a mix of our mother and fathers however some of our attributes of appearance may be similar to our grandparents. As genes can sometimes seemingly ‘miss a generation’ but the genes are still passed down just not aesthetically visible. Our genes also affect the timing of when puberty occurs, but environmental factors such as nutrition also have an effect. Biological influences are things that affect a child before birth, better known as a foetus at this stage of development. However, this does not only include the time period from conception till birth, the 3 months prior to conception are also very important when it comes to a child’s development. For example, a mother who smokes regularly in the 3 months before conception or during pregnancy puts themselves at double risk of developing placental problems and therefore increases the risk of danger to their baby. There are a few different placental problems that could occur, I won’t go into great detail but some require a caesarean section. This would mean a long recovery in hospital putting stress upon the mother and withholding important early bonding time.
Another problem that could occur is an early rupture of the membrane which will induce labour before the baby is fully developed; missing out on crucial development time in the womb can cause various health problems. Chances of placental abruption are also increased, which is separation of the placenta from the attachment site which causes problems for both the mother and the foetus. Smoking also impairs the development of the placenta, which is problematic because it reduces blood flow to the foetus. When the placenta doesn’t develop fully the umbilical cord, which transfers oxygen and nutrients from the mothers blood, can’t transfer enough oxygen and nutrients to the foetus. Without a generous and regular supply of these vital nutrients the baby will not be able to fully grow and develop. It also increases the chance of developing placenta previa, a condition in which the placenta grows over the cervical opening. Smoking may harm the unborn baby’s lungs and cause birth defects. Babies born to women who smoke during pregnancy also have roughly 30% higher odds of being born prematurely.  French academics in an IVF clinic did a study with time lapse photography to show that embryos of smoking women develop more slowly. Researchers watched 868 embryos develop – 139 from smokers.
They took regular pictures of an egg from the moment it was fertilised until it was ready to be implanted into the mother. As eggs fertilised through IVF initially develop in the laboratory before being implanted in the mother, it gave doctors a unique opportunity to film the embryos as they divide into more and more cells. At all stages of development the embryos from smokers were consistently a couple of hours behind.  The study cannot say what impact the slower development has, or if it affects the chances of successfully giving birth to a child but slow development can be related to various different health problems when the foetus is born and also developing them in later life. Mothers who drink alcohol also put their child at risk of developing slowly. Recent research suggests that a mother who drinks a large glass of wine a day stunts their child’s growth up to the age of nine. ‘Scientists at Harvard Medical School found pregnant women who had three units of alcohol a day had babies with a lower height, weight and head circumference than light or non-drinkers.’  http://www.dailymail.co.uk/news/article-2188846/Women-drink-pregnancy-affect-child-s-growth-years.html
The researchers tested a group of 85 pregnant women, defined as ‘heavy drinkers’, who drank the equivalent of at least a large glass of wine a day (250ml). This group was compared with a group of 63 women who either did not drink at all or drank ‘lightly’ – defined as less than one unit a day. The study is one of the longest-running into the effects of alcohol on the unborn child, their children’s height, weight and head circumference was measured at the ages of six months, a year, five years and nine years. Lead author Dr Robert Carter said: ‘We found that children born to women who drank heavily during pregnancy had reductions in weight, height, and head circumference, an indicator of brain growth. This alcohol-related growth restriction was present in early infancy and persisted through to nine years of age.’ He also said the effects may be permanent and affect brain development, giving children a lower IQ for life. So not only do drinking mothers effect development in the womb, evidence has shown that it effects their physical growth throughout childhood.
Also more importantly it is thought that their brain development could be effected which would affect intellectual and emotional development throughout life. When you are pregnant it is important to watch what goes into your body, as what goes into you goes into your baby too. As oxygen and nutrients are passed through the body and then into the baby any other substances in the blood will be passed to them too, some of which could be seriously harmful to the foetus. All medicines and drugs should be taken with extreme caution and only if strongly recommended by a doctor that the benefit to you is greater than the risk to the baby. Of course illegal ‘street’ drugs should be avoided at all costs, pregnant or not, but I’ll move on to that later. Prescription drugs and even over the counter medicines can still be extremely harmful to the foetus and cause serious development problems. Even though there have been studies in the U.S and here in the U.K it cannot be certain that any drug is 100% safe to take during pregnancy and some of the evidence from these studies have insufficient data to determine the safety. It’s very important to pay attention to the medication you take whilst pregnant, especially in the first trimester which is a crucial time for baby development. It is recommended that if you were taking prescription medication before you were pregnant that you ask a doctor about the safety of continuing these medications.
The benefit to you and the risk to your baby will be weighed up by the professional when making their recommendations. With some medications and conditions, the risk of not taking them may be more serious than the potential risk associated with taking them. All this depends on the individual and the circumstances. Taking certain prescription medications can cause serious birth defects. Aspirin may cause cardiac problems and low birth weight. Dextromethorphan, an active ingredient in cough medicine increases the risk of birth defects. Ephedrine may cause heart-rate problems and birth defects. Cardiac malfunction is also an effect of ibuprofen.
Accutane causes major birth defects. There are many over-the-counter and prescription drugs that may be harmful to an unborn baby and professional advice should always be sought after about all medications taken. High levels of caffeine can cause low birth weight, lung problems, mental disabilities and birth defects. It is because of this that experts recommend no more than 200mg of caffeine per day during pregnancy. Glues and solvents may cause low birth weight, facial and heart defects, joint issues and small head size. Even some herbal remedies have been proven to be dangerous to the foetus during pregnancy, therefore it is always appropriate to check everything with family planner/health visitor.
The effects of illegal drugs can be far more dangerous to the baby. Major birth defects, miscarriage, low birth weight, physical deformities and more specifically heart and organ abnormalities. Cocaine use has been shown to increase the risk of placental abruption, cocaine addiction in the foetus and material dearth. Cannabis can cause learning and behavioural problems. Ecstasy has been linked to learning and memory disabilities. Methamphetamine use may cause IUGR, a condition that impairs foetal growth and could result in stillbirth or the delivery of a low birth weight baby.
Heroine use during pregnancy may cause premature birth and congenital abnormalities. ‘About 3% of newborns have a “major physical anomaly”, meaning a physical anomaly that has cosmetic or functional significance. Congenital anomalies involving the brain are the largest group at 10 per 1000 live births, compared to heart at 8 per 1000, kidneys at 4 per 1000, and limbs at 1 per 1000. All other physical anomalies have a combined incidence of 6 per 1000 live births. Congenital anomalies of the heart have the highest risk of death in infancy, accounting for 28% of infant deaths due to congenital anomaly, while chromosomal anomalies and respiratory anomalies each account for 15%, and brain anomalies about 12%.’
The effects of cocaine include major birth defects, miscarriage, low birth weight, physical deformities, and heart and organ abnormalities. Cocaine use increases the risk of placental abruption, cocaine addiction in the fetus, and maternal death. Marijuana use can cause learning and behavioral problems. Ecstasy has been linked to learning and memory disabilities. Methamphetamine use may cause IUGR, a condition that impairs fetal growth and could result in stillbirth or the delivery of a low birth weight baby. Heroin use during pregnancy may cause premature birth and congenital abnormalities.
“You often hear the word environment, but do you stop to think what it really means, what it contains, and how it affects you? The actual definition of environment is the circumstances, objects, or conditions by which one is surrounded (Merriam-Webster dictionary).”
Environmental factors can have a strong influence on the development of an individual. In the context of environmental health, the term ‘environmental exposure’ means contaminants of the natural environment of air, water, and soil. Chemicals such as metals and solvents and biological agents such as toxins released from mould and bacteria. The term also encompasses lifestyle factors such as diet and physical activity. For common diseases such as obesity and asthma, environmental exposure represents an important factor contributing to the development and progression of disease.
Whether an individual develops disease as a result of environmental exposure also depends on the type of exposure, amount of exposure and the timing of exposure with regard to a person’s age and stage of development. Although samples of chemicals and toxins can be taken from various different environments, this does not effectively measure the amount of exposure an individual is susceptible to. Sometimes exposure to humans is tested through blood or urine samples, measured by the amount of a specific chemical, biological or dietary factor. These measurements will tell us how much a person was exposed to but they provide no information about how an individual is responding. There is also a lack of accuracy in measuring environmental influences and the body’s response to these factors.