Woman’s health, nutrition, and wellbeing from preconception to pregnancy is critical for ensuring positive pregnancy. It has a profound influence on her child as an infant, it also affects the child’s risk of obesity and related chronic disease as an adult.
The baby developing in the womb is dependent on the mother for all its nutritional requirements and when this is inadequate or unbalanced, it brings about permanent changes / adaptations in the fetus, increasing the chances of developing diseases in later life such as obesity, diabetes, hypertension, cardiovascular problems, metabolic syndrome and osteoporosis.
The nutritional and health status of women as they enter pregnancy plays a key role in placental function and subsequent growth and development of the fetus. The fetus is dependent on the range of micronutrients circulating in the mother’s blood supply for optimal development. The placenta regulates the supply of nutrients for fetal growth and ultimately influences the long-term health of the newborn. Nutritional status prior to conception may also influence offspring health and cognitive outcomes by affecting the growth and development of the brain, liver and pancreas during the first few weeks of pregnancy. Brain development begins shortly after conception. Iron, in particular, plays an important role in early fetal brain development and other micronutrients, such as vitamin B6, B12, folic acid and zinc are influential. As women may not realize they are pregnant during the first 1–2 months, optimal nutrition prior to pregnancy is critical.
Pre-pregnancy overweight and obesity are associated with impaired fertility and risk of preterm birth. It also increases the risk of gestational hypertension and diabetes, which are strongly correlated with large-for-gestational-age infants and can alter the offspring’s glucose and lipid metabolism and induce hypertension.
Obesity during pregnancy promotes insulin resistance, impaired glucose tolerance, hypertension and increased fat levels in offspring which extends into adulthood. Increased fat, glucose intolerance and altered appetite regulation are observed in the offspring with even mild maternal overeating. Pregnant women who are obese (from excess energy intake) may simultaneously have multiple nutrient deficiencies too.
Gestational diabetes mellitus (GDM) is another form of nutritional imbalance in pregnancy and is strongly related to obesity. The presence of GDM increases the risk of either restricted or excess fetal growth, fetal adiposity, predisposition to obesity, impaired glucose tolerance, type 2 DM in offspring throughout life.
Hypertension during Pregnancy–Even when maternal nutrition is adequate, reduced uterine blood flow in conditions such as maternal hypertension may cause impaired fetal growth by severely limiting fetal nutrient supply.
Maternal calcium and vitamin D status helps regulate fetal skeletal development and deficiency may affect the offspring’s bone health and result in reduced bone density.
Vitamin B-12 deficiency in the mother, especially if she is folate replete, is associated with increased body fat and insulin resistance in children. It is important to maintain an optimum level of B-12 through out of your pregnancy.
The risk of obesity increases at both ends of birth weight spectrum.
Increased birth weight leads to increased risk for childhood and adult obesity and low birth weight and intra uterine growth retardation (IUGR) is also an important factor predisposing to central obesity and degenerative disease in later adult life. Low birth weight in full term infants reflects IUGR.
Low birth weight and its consequences
If the mother’s diet is deficient in energy, protein and / or certain micro-nutrients during pregnancy, she signals to her unborn baby that the environment it is about to enter is likely to be harsh. The baby responds to these signals by adaptations such as reduced number of cells in key organs, reduced body size and altered metabolism for survival. These adaptations in the fetus become permanent as they occur during the critical period of the child’s development. These tend to be more harmful when nutrition is more abundant in the post-natal environment than it had been in the pre-natal environment.
Altered body composition: Due to inadequate nutrition, the fetus sacrifices tissues that require high quality building blocks like muscle or bone and instead lays down less demanding tissues like fat, resulting in reduced lean body mass and a high overall body fat mass in adolescent and adult life.
Changes in structure and functional capacity of various organs: Growth failure in fetus leads to permanent changes in the number, structure of cells and function of various organs such as nephrons in kidney, cardiomyocytes in heart, neurons in brain, pancreatic beta cells, thereby decreasing the lifelong functional capacity of these organs.
Effect on kidney and risk of developing hypertension: Hypertension is initiated by the reduced number of nephrons found in people who are small at birth
Effect on pancreas and skeletal muscles leading to insulin resistance and diabetes: Inadequate maternal nutrient intake and low availability of protein causes permanent changes in structure and function of beta cells of pancreas leading to progressive reduction in insulin secretion and eventual development of type 2 diabetes in adult.
Effect on heart, circulatory system and its effect on cardio-vascular disease
Other effects: Poor intrauterine growth is also associated with reduced physical work capacity in adult life, impaired cognitive function and an increased risk of low birth weight in the next generation.
Advice for healthy diet and lifestyle for optimal health before conception and even in all the three trimesters to pregnancy to optimize your as well as your baby’s health is very important.