IntroductionThere are a range of adverse health effects associated with maternal under-nutrition. It can affect both the pregnant woman and developing baby in the short and long-term. Show
Under-nutrition can be classified as either:
Malnutrition occurs when an individual consistently consumes less energy (measured in calories and obtained from proteins and carbohydrates) than they expend. Malnutrition results in the individual being underweight and experiencing greater ill-health. Micronutrient deficiency is a condition which occurs when an individual consumes enough food overall, but does not consume enough of the specific micronutrients they need to maintain the growth and function of specific body parts and systems. For example, calcium deficiency can affect the growth of bones and teeth. Health risks associated with malnutrition before pregnancyA woman’s nutritional status at the time she becomes pregnant influences her health during pregnancy and the health of her baby. It is determined largely by her nutritional intake before pregnancy. If a woman is under-nourished prior to conception because she does not eat enough, she may be malnourished and underweight at the time she conceives. This will have an ongoing effect on her nutritional status throughout the pregnancy. Her nutritional status at the time she becomes pregnant is also an important factor influencing the health of the foetus, as well as the long term health of the infant.For more information, see Importance of Nutrition Before Pregnancy.
Women who are under-nourished (have a BMI of <18.5kg/m2) at the time of conception are unlikely to improve their nutritional status during pregnancy, when their bodies have additional demands due to the growing baby. They may fail to gain sufficient weight during pregnancy and have a higher risk of maternal mortality (dying whilst pregnant) than normal weight women.
Under-nourished women may also lack the nutritional stores required to support embryo growth. Embryo refers to a fertilised egg, before it begins to take on human characteristics (at which stage it is referred to as a foetus). In the first few days after conception the embryo exists in the woman’s womb but has not yet implanted into the lining of the womb where it will grow throughout the pregnancy. This is known as the pre-implantation period and is the period of pregnancy in which cells divide and replicate most rapidly. Maternal malnutrition can adversely affect the division and replication of cells in the embryo at this stage, impairing its development. Impaired embryo development in turn adversely effects the development of the foetus in the later stages of pregnancy. A woman’s nutritional status at the time she becomes pregnant also influences the differentiation of cells in the embryo into foetal and placental cells. When the embryo implants into the wall of a woman’s uterus, it develops two types of cells, those that will become the foetus and those which will become the placenta (the structure which nourishes and supports the foetus during pregnancy). In undernourished women, a greater number of cells are likely to form the placenta compared to the foetus, meaning that the foetus begins its life smaller than it should do. This can lead to restricted foetal growth and increases the risk of the baby being born at a low-birth weight (<2.5kg). Low birth weight is in turn associated with a range of adverse outcomes in childhood and later in life. Foetal development is also affected by maternal nutritional status before pregnancy. It is during the first five weeks of pregnancy when the foetus develops most of its organs (e.g. heart, brain, lungs). At this stage the foetus is most vulnerable to the mother’s malnutrition. Nutritional deficiencies at this time may retard the growth of the foetus’s organs. As the woman is usually unaware she is pregnant at this early stage, she can only ensure she is well nourished by eating properly before she becomes pregnant.
When a foetus is malnourished in the early (and later) stages of pregnancy it may also have a lifelong programming effect which predisposes the baby to chronic health conditions later in life. For example, the foetus may adapt its metabolism to cope with malnutrition by reducing the amount of insulin and glucose produced. Such adaptation has been shown to permanently program the metabolic system and increase the risk of chronic health conditions later in life such as type 2 diabetes. Health risks associated with micronutrient deficiency before pregnancyMicronutrient status at the time of conception is also determined by historic nutrient consumption, and deficiency in one or more micronutrients can detrimentally affect the health of the mother and her baby.
Maternal deficiency in particular micronutrients can also affect the development and health of the foetus. For example:
Health risks associated with malnutrition during pregnancy
Pregnant women who receive inadequate nutrition experience greater maternal morbidity (are more likely to be ill whilst pregnant) and have a higher risk of poor pregnancy outcomes (e.g. premature birth, miscarriage). They also have an increased risk of developing the following conditions:
As mentioned above, maternal under-nutrition causes metabolic and other changes in the foetus, which program its metabolic responses following birth. For example, a foetus that is malnourished adapts by reducing insulin and glucose production. This is thought to program and permanently alter the individual’s glucose and insulin metabolism throughout their life and increase the risk of chronic nutritional disorders including type 2 diabetes mellitus, metabolic syndrome and obesity. For example, one study showed that the lower the birth weight of an infant, the higher the risk of developing type 2 diabetes. Men who were born at a very low weight were seven times more likely to develop diabetes compared to men born at a high weight. However, the effects of maternal under-nutrition vary depending on the stage of pregnancy at which under-nutrition is experienced. For example, one study reported that exposure to maternal malnutrition in the first trimester of pregnancy was associated with an increased risk of obesity and coronary heart disease, while malnutrition in the second or third trimester was associated with poor glucose metabolism.The offspring of women who experienced under-nutrition during pregnancy have an increased risk of developing:
The greatest brain growth occurs between the 3 months before birth and 2 years of age. It is at these stages that the development of the brain’s nerve system and the connection between nerves is at its peak and so the brain requires the most energy to maintain its growth. The nerve system made during this time impacts the way the brain is structurally and functionally organised (cortical organisation) throughout life. Poor foetal development has been associated with the following adverse health and development outcomes later in life:
Health risks associated with micronutrient deficiency during pregnancyThere are also numerous maternal and foetal health risks associated with micronutrient deficiency during pregnancy, that is, deficiency in particular micronutrients such as folate, and vitamin B12.
A woman’s deficiency in particular micronutrients whilst she is pregnant has detrimental effects on particular aspects of foetal development. Foetal health risks which arise as a result of deficiency on particular micronutrients include:
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All content and media on the HealthEngine Blog is created and published online for informational purposes only. It is not intended to be a substitute for professional medical advice and should not be relied on as health or personal advice. Always seek the guidance of your doctor or other qualified health professional with any questions you may have regarding your health or a medical condition. Never disregard the advice of a medical professional, or delay in seeking it because of something you have read on this Website. If you think you may have a medical emergency, call your doctor, go to the nearest hospital emergency department, or call the emergency services immediately. How does malnutrition affect the fetus?During pregnancy, poor diets lacking in key nutrients – like iodine, iron, folate, calcium and zinc – can cause anaemia, pre-eclampsia, haemorrhage and death in mothers. They can also lead to stillbirth, low birthweight, wasting and developmental delays for children.
How can malnourishment of mother during pregnancy affect the baby in future life?Maternal underweight is likewise associated with offspring growth and development, including increased risk for PTB, low birth weight (LBW), under-five mortality, and poor mental and physical development [3].
Can malnutrition during pregnancy slow fetal growth?Placental and fetal growth is most vulnerable to maternal nutrition status during the peri-implantation period and the period of rapid placental development (the first trimester of gestation). Maternal undernutrition or overnutrition during pregnancy can impair fetal growth.
What birth defects are caused by malnutrition?Without enough nutrients, a baby is at higher risk of neural tube defects, brain damage, premature birth, underdevelopment of organs, death and more.
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