Challenges To Maternal Homeostasis

In the approximately 265 days that elapse between fertilization and delivery of a full-term infant, the mother provides all of the resources required to transform a single pluripotential cell into a complete new individual comprised of more than 600 billion highly specialized cells and weighing about 3.5 kg. Demands on maternal homeostasis to support these remarkable events are not constant but change as pregnancy progresses. Throughout the pregnancy her homeostatic control mechanisms ensure a hospitable environment of constant temperature, oxygen supply, waste disposal, and availability of nutrients, minerals, and vitamins. In addition, she supports growth and development of the placenta and its extraordinary metabolic activity. To house the growing fetus and placenta, her uterus grows from around 50 g to more than 1 kg and from about 7 cm to more than 40 cm in length. It also acquires the contractile capacity required to expel the baby at term. Her breasts grow and develop, and she increases her fat stores in anticipation of providing nourishment for her newborn child. The overall cost to the mother in increased energy expenditure is about 85,000 calories (~300 Cal/day), which must be derived from the diet or fat reserves. Of this, only about one-third is consumed by the fetus to support biosynthetic and metabolic activities. About one-third is consumed by the placenta to support biosynthetic and transfer processes, and much of the remainder fuels the additional workload imposed on the heart, respiratory muscles, and kidneys.

Pregnancy is traditionally dated from the time of the last menstrual period, although ovulation and fertilization occur about 2 weeks later. In describing the progress of pregnancy, it is customary to consider the nine months of gestation in three-month intervals, or trimesters. Fetal growth progresses exponentially at a rate of about 1.5% each day until about the middle of the third trimester, when it may slow somewhat (Fig. 1). By the end of the first trimester, the fetus attains only about 2% of its size at birth. Consequently, its metabolic needs are small in the first trimester, and maternal resources are directed toward fueling the rapid growth of the placenta and establishing the infrastructure that will support fetal development in the second trimester and, especially, the third trimester, when the bulk of fetal growth takes place. Metabolic demands of the early weeks are dominated by requirements of the rapidly expanding syncytiotropho-blast and formation of the placenta, which is not complete until about the 12th week. While placental growth slows as pregnancy progresses, its biosynthetic and nutrient transfer activities persist and intensify as term approaches. Even at term, when its mass is less than 15% of that of the fetus, the placenta consumes about 40% of the oxygen extracted from the uterine circulation. Per gram of tissue, the placenta consumes oxygen at about the same rate as the adult brain. About 30% of placental oxygen uptake is consumed in maintaining the ionic gradients that support solute transport, and another 30% is consumed in protein synthesis.

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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