Final answer:
During pregnancy, a mother requires additional nutrients, including calories, proteins, lipids, vitamins, and minerals, to support fetal development and accommodate the physiological changes happening in her body.
Step-by-step explanation:
Pregnancy is a time of increased nutrient needs because the mother must consume enough nutrients for the fetus as well as for herself.
There is a need for additional calories, proteins, lipids, vitamins and minerals to support the various physiological changes and growth occurring during this period.
A pregnant woman typically needs an extra 300-400 calories per day, particularly in the last trimester when fetal growth is most rapid.
Specifically, during pregnancy, there is an increase in maternal blood volume by 30%, respiratory minute volume by 50%, and significant weight gain, which is essential for the various bodily changes that support the fetus.
Hormone changes also lead to increases in thyrotropin, prolactin, and ACTH that affect metabolism and prepare the body for breastfeeding.
Fat storage during pregnancy, which is approximately 2.3 kg (5 lbs), serves as a reserve for the increased metabolic demand during breastfeeding.