The correct answer is choice A.Increased progesterone levels are primarily responsible for fatigue and mood swings during pregnancy.Progesterone is a hormone that relaxes the muscles and causes sleepiness and tearfulness.

Choice B is wrong because estrogen levels actually increase during pregnancy, especially in the first 12 weeks.

Estrogen is associated with serotonin, a brain chemical that regulates mood.Changes in estrogen levels can cause anxiety and irritability.

Choice C is wrong because thyroid hormone levels usually decrease during pregnancy, not increase.Low thyroid hormone levels can cause symptoms such as weight gain, constipation, and cold intolerance.

Choice D is wrong because insulin resistance usually occurs later in pregnancy, not early on.Insulin resistance can cause high blood sugar levels and increase the risk of gestational diabetes.

Normal ranges for pregnancy hormones vary depending on the stage of pregnancy and the laboratory methods used.

However, some general ranges are:

• Progesterone: 9 to 47 ng/mL in the first trimester, 17 to 147 ng/mL in the second trimester, and 55 to 200 ng/mL in the third trimester

• Estrogen: 15 to 60 pg/mL in the first trimester, 150 to 1,300 pg/mL in the second trimester, and 1,500 to 6,000 pg/mL in the third trimester

• Thyroid stimulating hormone (TSH): 0.1 to 2.5 mIU/L in the first trimester, 0.2 to 3.0 mIU/L in the second trimester, and 0.3 to 3.0 mIU/L in the third trimester

• Insulin: less than 25 mIU/mL before meals and less than 120 mIU/mL one hour after meals

The correct answer is choice A. Maintaining the endometrium.HCG is a hormone produced by the placenta during pregnancy that helps thicken the uterine lining and tells the body to stop menstruating.

This supports the implantation and growth of the embryo.

Choice B is wrong because hCG does not stimulate milk production.

That is the role of another hormone called prolactin.

Choice C is wrong because hCG does not inhibit uterine contractions.

That is the role of another hormone called progesterone.

Choice D is wrong because hCG does not regulate the metabolic rate.

That is the role of another hormone called thyroid-stimulating hormone (TSH)

. Increased insulin resistance.This is because during pregnancy, the placenta produces hormones such as human placental lactogen (hPL) and placental growth hormone that increase the mother’s blood glucose levels and decrease her sensitivity to insulin.This causes increased urination and fatigue as the body tries to eliminate excess glucose and cope with the higher energy demands of pregnancy.

Choice A is wrong because increased estrogen levels do not cause increased urination and fatigue.Estrogen is a hormone that helps develop the female sexual traits and maintain a healthy pregnancy.

It does not affect blood glucose levels or insulin sensitivity.

Choice C is wrong because decreased progesterone levels do not cause increased urination and fatigue.Progesterone is a hormone that stimulates the thickening of the uterine lining for implantation of a fertilized egg and prevents uterine contractions during pregnancy.

It does not affect blood glucose levels or insulin sensitivity.

Choice D is wrong because increased thyroid hormone levels do not cause increased urination and fatigue.Thyroid hormones are responsible for regulating the metabolism, growth and development of the body.

They do not affect blood glucose levels or insulin sensitivity.

The correct answer is choice C. Estrogen.Estrogen is a hormone that is normally formed in the ovaries and is also made by the placenta during pregnancy to help maintain a healthy pregnancy.Estrogen helps the uterus grow to accommodate the growing baby and maintains a well-functioning uterine lining and placenta.Estrogen also plays a role in regulating other essential pregnancy hormones and in developing fetal organs such as the lungs, liver, and endocrine glands.

Choice A is wrong because hCG (human chorionic gonadotropin) is a hormone that is only made during pregnancy and is mainly responsible for maintaining the corpus luteum, which produces progesterone.hCG levels rise a lot during the first trimester and may cause nausea and vomiting, but it does not directly stimulate uterine growth or fetal organ development.

Choice B is wrong because progesterone is a hormone that is made by the ovaries and by the placenta during pregnancy.It stimulates the thickening of the uterine lining for implantation of a fertilized egg and prevents uterine contractions during pregnancy.

Progesterone also supports fetal growth and development, but it is not the main hormone for stimulating