Metabolism

■ Metabolic modifications begin soon after conception and are most marked in the second half of pregnancy when fetal growth requirements increase.

■ The uterus and placenta require carbohydrate, fat, and amino acids. Carbohydrate

The placenta is freely permeable to glucose, which increases availability to fetus.

First 20 Weeks

Insulin sensitivity increases in first half of pregnancy.

■ Fasting glucose levels are lower.

■ This favors glycogen synthesis and storage, fat deposition, and amino acid transport into cells.

After 20 weeks

After 20 weeks, insulin resistance develops and plasma insulin levels rise.

■ A carbohydrate load produces a rise in plasma insulin 3 to 4 times greater than in the nonpregnant state, but glucose levels also are higher.

■ This reduces maternal utilization of glucose and induces glycogenolysis, gluconeogenesis, and maternal utilization of lipids as energy source.

■ Despite these high and prolonged rises in postprandial plasma glucose, the fasting level in late pregnancy remains less than nonpregnant levels.

Amino Acids

■ Plasma concentration of amino acids falls during pregnancy due to he-modilution.

■ Urea synthesis is reduced.

Lipids

Goal in pregnancy is to increase the availability of glucose for the fetus, while the mother utilizes lipids.

Pregnancy is an anabolic state.

The optimal time to screen for glucose intolerance/ diabetes mellitus (DM) in the pregnant female is at 26 to 28 weeks' GA.

■ All lipid levels are raised, with the greatest increases being in the triglyceride-rich component.

■ Lipids cross the placenta.

■ Hyperlipidemia of pregnancy is not atherogenic, but may unmask a pathologic hyperlipidemia.

■ Early in pregnancy, fat is deposited.

■ By midpregnancy, fat is the primary source of maternal energy.

■ Postpartum, lipid levels return to normal.

Cholesterol

■ There is an increased turnover of cholesterol from lipoproteins, creating an increased supply to most tissues and increased supply for steroid production.

■ Total cholesterol is raised postpartum in all mothers, but can be reduced by dieting after delivery.

Triglycerides, very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) increase during pregnancy.

Normal pregnancy is a hyperlipemic, as well as a glucosuric, state.

The increase in cholesterol excretion results in increased risk of gallstones.

Drugs/Other Substances

■ Plasma levels of phenytoin fall during pregnancy.

■ The half-life of caffeine is doubled.

■ Antibiotics are cleared more rapidly by the kidney.

Get Pregnant - Cure Infertility Naturally

Get Pregnant - Cure Infertility Naturally

Far too many people struggle to fall pregnant and conceive a child naturally. This book looks at the reasons for infertility and how using a natural, holistic approach can greatly improve your chances of conceiving a child of your own without surgery and without drugs!

Get My Free Ebook


Post a comment