Endocrine Changes in pregnancy

• The endocrine system undergoes significant changes to regulate the metabolic, reproductive, and immunological functions of pregnancy



• The main endocrine changes include:
  • Increased human chorionic gonadotropin (hCG): The hormone produced by the placenta that maintains the corpus luteum (the structure that produces progesterone) and stimulates fetal growth increases during pregnancy. The hCG levels peak at 8 to 10 weeks of gestation and then decline until term. The normal range of hCG in pregnancy is based on the gestational age and varies widely among individuals.
  • Increased progesterone: The hormone produced by the corpus luteum and then by the placenta that maintains the endometrium (the lining of the uterus), inhibits uterine contractions, and prepares the breasts for lactation increases during pregnancy. The progesterone levels rise steadily throughout pregnancy and reach their highest point at term. The normal range of progesterone in pregnancy is based on the gestational age and varies widely among individuals.
  • Increased estrogen: The hormone produced by the ovaries and then by the placenta that stimulates uterine growth, increases blood flow to the uterus and breasts, and enhances fetal organ development increases during pregnancy. The estrogen levels rise steadily throughout pregnancy and reach their highest point at term. The normal range of estrogen in pregnancy is based on the gestational age and varies widely among individuals.
  • Increased thyroid hormones: The hormones produced by the thyroid gland that regulates the metabolic rate, protein synthesis, and fetal brain development increase during pregnancy. The thyroid hormones increase by 50% to 100% during pregnancy due to increased hCG levels, increased estrogen levels, and increased thyroid-binding globulin (the protein that carries thyroid hormones in the blood). The normal range of thyroid hormones in pregnancy is based on the gestational age and varies widely among individuals.
  • Increased insulin resistance: The reduced ability of the body to respond to insulin (the hormone that lowers blood glucose levels) increases during pregnancy. This is due to increased placental hormones such as human placental lactogen (hPL), cortisol, and progesterone that antagonize the action of insulin. The insulin resistance increases progressively throughout pregnancy and reaches its highest point at term. The normal range of insulin resistance in pregnancy is based on the individual’s pre-pregnancy glucose tolerance and varies widely among individuals.
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  • Increased prolactin: The hormone produced by the pituitary gland that stimulates milk production and inhibits ovulation increases during pregnancy. The prolactin levels increase by 10-fold to 20-fold during pregnancy due to increased estrogen levels and suckling stimulation. The normal range of prolactin in pregnancy is based on the gestational age and varies widely among individuals.
  • The endocrine changes may cause symptoms such as fatigue, mood swings, breast tenderness, or polyuria (increased urination) that are normal or abnormal depending on the severity, duration, and frequency
  • The endocrine changes result in increased hormonal feedback (the process by which hormones regulate their own secretion or the secretion of other hormones) and decreased hypothalamic-pituitary-ovarian axis (the system that controls the reproductive function) that regulate the metabolic, reproductive, and immunological functions of pregnancy
  • The endocrine changes may cause symptoms such as fatigue, mood swings, breast tenderness, or polyuria (increased urination) that are normal or abnormal depending on the severity, duration, and frequency