Maternal Nutrition and Fetal Health and OutcomeChapter 1

The recent intensive efforts for improving child survival status and global concerns for the child's health have drawn attention of researchers, national policy-makers and administrators to the impact of maternal nutritional status on fetal and neonatal health and outcome. The extremes of maternal nutritional status are likely to adversely affect the fetus. These may result in fetal maldevelopment, fetal death, untimely intrauterine growth retardation, etc.

The neonatal size is strongly related to maternal body mass index (BMI), weight, height and even maternal birth weight. The nutrition of female throughout her life (including fetal and childhood) as well as during pregnancy influences the growth of her fetus. Not only is mortality high among LBW babies, these small babies grow up to be small adult and, in the case of girls, small mothers who in turn give birth to LBW babies (Fig. 1.1). It has been observed that ‘maternal environment’ has a more powerful influence on fetal growth than genes. The birth weights of babies born after ovum donation are strongly related to the weight of the recipient mother, but not that of the donor mother.¹ The ICMR multicentric study on high-risk urban slum and rural population showed a higher perinatal (50–60/1000 birth) and neonatal (35–61/1000 live births) mortality with maternal weight of 40 kg or less. The prevalence of coronary heart disease (CHD) was about 11 percent overall, and as in western studies, higher in those of lower birth weights. It is also higher in those where mothers were below average weight at antenatal booking. Lower birth weight is also associated with poorer adult lung functions.²

According to a study from Finland, mortality from CHD was more in men and women where mothers were short and had a high BMI.³ The prevalence of diabetes was also high in offspring of mothers with a higher body weight and larger external pelvic diameters. BMI is useful in predicting LBW and small or large for getational age infants. A low maternal weight is associated with LBW and overweight women deliver a greater proportion of large for gestational age infants.^4,5

An expectant mother needs to be provided with adequate nutritional intake for maternal and fetal tissue growth and her own usual maintenance requirements. An acute (or) chronic deprivation of dietary intake may result in a poor pregnancy outcome. Reduced maternal intake of energy and protein during pregnancy results in restricted fetal (animal study) growth.⁶ According to Pune maternal nutritional study, although there were no association between neonatal size and the mother's energy and protein intakes, her intake of milk at 18 weeks and green leafy vegetable and fruits at 28 weeks were directly related to babies size.⁷ Women consuming green leafy vegetables (GLVs) every alternate day or more had babies almost 200 g heavier, than those who never ate them. There are some evidences that improving the micronutrient quality of mother's diets results in increased fetal growth. It has been observed that exposure to famines during late gestation, was associated with glucose intolerance, insulin resistance and increase in type 2 diabetes. Early gestational exposure was associated with higher LDL/HDL cholesterol concentrations and higher BMI and waist circumference. It is also observed that the balance of maternal protein and carbohydrate intake during pregnancy is related to blood pressure in the offspring.

The American national research council recommendations of daily dietary allowances for women before pregnancy and during pregnancy and lactation are as per Table 1.1.⁹

Traditionally pregnant and lactating women have been recognized as a vulnerable group from the health and nutritional point of view, requiring additional nutritional suport.¹⁷

Extra calories are needed during pregnancy to build up her own tissue, to build fat stores, to make breast-milk and for growth of the fetus and placenta. Pregnancy requires an additional 80,000 kcal, which are accumulated primarily in the last 20 weeks. Caloric increase of, 300 kcal daily throughout the pregnancy is recommended by the National Research Council. Her gut absorbs nutrient better and her body uses them more efficiently than when she is not pregnant. Calories are necessary for energy and whenever caloric intake is inadequate, protein is metabolized for energy supply rather than being spared for its vital role in fetal growth and development.

Proteins are essential for fetal growth and metabolism as these provide essential amino acids and nitrogen. To the basic protein needs of the non-pregnant women are added the demands for growth and repair of the fetus, placenta, uterus and breasts and increase maternal blood volume. During the last 6 months of pregnancy about 1 kg of protein is deposited, amounting 5 to 6 gm/day. It is desirable that the manority of the protein be supplied from animal sources such as meat, milk, eggs, cheese, poultry and fish because they furnish amino acids in optimal combination. Milk and milk products are considered nearly ideal sources of nutrients, especially protein and calcium, for pregnant (or) lactating women.

Of the approximately 300 mg of iron transferred to the fetus and placenta and the 500 mg incorporated into the expanding maternal hemoglobin mass, nearly all is used after mid pregnancy. During that time, iron 5requirements imposed by pregnancy and maternal excretion total about 7 mg/day.

If folic acid is administered in the periconceptional period, i.e. before and during early pregnancy then it is known to prevent the neural tube defects. Since 1992, the public health services have recommended that all woman capable of becoming pregnant should consume 0.4 mg of folic acid daily throughout their childbearing age.

The pregnant woman retain about 30 mg of calcium, most of which is deposited in the fetus late in pregnancy. This amount of calcium represent only about 2.5 percent of total maternal calcium, most of which is in bone, and which can readily be mobilized for fetal growth.

Severe zinc deficiency may lead to poor appetite, sub-optimal growth and impaired wound healing. Profound zinc deficiency may cause dwarfism 6and hypogonadism. It may also lead to specific skin disorder acrodermatitis enteropathica.

The effect of food supplementation to under nourished women on course and outcome of pregnancy were under taken in the National Institute of Nutrition, Hyderabad,¹⁴ India which showed that food supplements during pregnancy resulted in improvements in birth weight and reduction in prematurity rate. Studies from Guatemala,¹⁵ showed that calories were the critical components of dietary supplements in relation to improvement in birth weight.

By the 1970s, women were encouraged to gain at least 11.4 kg (25 Lb) to prevent preterm births and fetal growth restriction. In 1997, the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists recommended a weight gain of 11.5 to 16 kg (25–35 Lb) for women with normal pre-pregnancy body mass index. Normal physiological events cumulatively account for about 9 kg as fetus, placenta, amniotic fluid, uterine and breast hypertrophy, increased blood volume and retained extracellular and extravascular fluid. The remainder of the weight gain appears to be mostly maternal storage fat.¹⁶ Low maternal weight gain, BMI or skin folds in pregnancy are associated with higher offspring blood pressure and insulin resistance. Parker and Abrams,²⁵ showed that excessive weight gains were linked to large for gestational age infants and correspondingly increased cesarean delivery.¹⁷

Even with low cost balanced diets, which lower income groups can afford and which are composed entirely of vegetable foods and milk, can adequately meet the essential nutrient requirements.

As per American Dietetic Association “well planned vegetarian diets are consistent with good nutritional status”.¹⁸

Cereals and millets are rich sources of complex carbohydrates and along with pulses and vegetables they also provide dietary fiber. Cereals, nuts, vegetable fat (oils) and tubers are good source of energy. That vegetarian diets can provide the energy needs of body is hardly disputed.

The fatty acid composition of vegetable oils may be considered wholesome and indeed nutritionally superior to that of animal fats. Vegetarian diets can thus fully meet the nutritional needs with respect to fats and essential fatty acid requirement even more satisfactorily than animal fats.

Cereals are generally poor in the essential amino acid lysine and this lysine deficiency can be easily offset by the inclusion of pulses and legumes which are rich in lysine.

Vegetables, especially green leafy vegetables and fruits are rich sources of carotenoides (Specially B-carotene, which are precursors of vitamin A), vitamin C, iron and calcium. With a judicious combination of cereals, pulses, vegetables, fruit and milk, it should be possible to ensure a diet of good nutritive value, which would fully meet all essential nutrient requirements.

The risk of iron deficiency is greater with purely vegetarian diets as compared to nonvegetarian diets. Heme iron from cellular animal tissue is highly bioavailable. Vegetarians however rely on non-heme iron, which is relatively less well-absorbed than heme iron.

In fact there is nothing in modern nutrition science to suggest that meat intake is obligatory in order to ensure optimal nutrition.¹⁹ All this proves that vegetarian diet is adequate to fulfill the nutrition requirements of pregnant and lactating mothers.

Recent recommendations for the exclusive breastfeeding are till the age of 6 months. This has been necessitated by evidence of improved infant survival with early and sustained exclusive breastfeeding for the first 6 months of life.²⁰

Initially studies were carried out in UK on 1586 men in Sheffield⁵ and on 5654 men in Hertfordsihire.⁶ Later studies were carried out in two Indian hospitals one in Pune and another in Mysore related to fetal origin 11of adulthood diseases (FOAD). According to him the roots of coronary vascular disease (CVD) lay in the effect of poverty on the mother resulting in under nutrition in fetal life and early infancy.

Anemia is the most important and most common of all micronutrient deficiencies in pregnancy. Low dietary intake of iron and folate and poor bioavailability of iron from Indian diets were identified as factors responsible for iron and folate deficiency and consequent anemia. In India, anemia antedates pregnancy get aggravated due to the increased and unmet demands of pregnancy, blood loss during labor and advent of successive pregnancies perpetuate it.²¹

Various studies have shown that a combination of reduction in dietary intake to below habitual levels and simultaneous increase in physical activity causes a “break down” of normal adaptive processes and results in deterioration of maternal nutritional status and poor intrauterine growth of the fetus.²¹ Poor dietary intake during the pregnancy, hard physical work and anemia, result in poor weight gain during pregnancy. Inadequate weight gain results in LBW babies. According to study, conducted by Agarwal et al, the women who were undernourished, underfed and were doing heavy physical work for domestic duties, during pregnancy which negatively influenced infant weight and length at brith.²² However, pregnant resident doctors doing active duty didn't show any adverse effect on birth weight.²³ Conversely Hatch (1993) in American women on low-moderate and heavy exercise found increase in birth weight by 100 grams and 300 grams respectively.²⁴ Rabin (1990) also reported marginal increase in birth weight in British women doing full time employment and those having longer hours of sleep.²⁵ Maternal under nutrition has been associated with placental changes suggestive of hypoxia; resulting in reduced placento-fetal circulation, these changes possibly get aggravated due to hard physical activity. In contrast, well-nourished pregnant women undertaking regular exercises improve placento-fetal circulation.

Obviously the dual stress of pregnancy and lactation may be expected to widen the already yawning gap between actual dietary intakes and nutrient requirement investigations undertaken by the national institute of nutrition, Hyderabad, indicate that irrespective of the duration of lactation women who conceived during lactation weighed less in all the trimesters of pregnancy than those who conceived after lactation. The difference in body weight was more marked in the third trimester especially in women who conceived during the first six months of lactation. The reasons for this are as follows:

Studies indicate that gainful employment of urban women outside the house in jobs requiring only moderate physical activity is associated with

In the nineties, HIV infection has emerged as a major cause of severe forms of under nutrition both in men and women belonging to reproductive age group and in children.

There are various misconceptions, beliefs and tabors regarding the nutritional diet of pregnant and lactating mother in the developing countries like India due to the blind faith in the age-old rituals. Several foods are considered bad. Most of the women have apprehension that if they it more, baby will be large resulting in difficult delivery.²⁷ The list of food items which are avoided along with its suspected effects on pregnancy and lactation are as follows:

The available data of the 1980s shows that in the last two decades there had not been any substantial reduction in either the magnitude or severity of maternal under nutrition and anemia. In the 1990s, the primary health care infrastructure was available for screening of pregnant women for these problems. Hence, the alternative strategy of screening all pregnant women, tailoring the intervention according to their needs and monitoring them is possible through the existent infrastructure.¹³