Assessment of a pregnant woman reveals oligohydramnios. The nurse would be alert for the development of which condition?

Choice A: Striae gravidarum are stretch marks that appear on the abdomen, breasts, or thighs during pregnancy. They are caused by the tearing of the connective tissue in the dermis due to rapid growth or weight gain.

Choice B: Linea nigra is a dark vertical line that runs from the umbilicus to the pubic area. It is caused by increased melanin production due to hormonal changes during pregnancy. This is the correct choice because it matches the description in the question.

Choice C: Vascular spiders are dilated blood vessels that appear on the skin as red or purple spider-like lesions. They are caused by increased estrogen levels and blood volume during pregnancy. They are usually found on the face, neck, chest, or arms.

Choice D: Melasma is a condition that causes brown or gray patches on the face, especially on the forehead, cheeks, nose, or upper lip. It is caused by increased melanin production due to sun exposure and hormonal changes during pregnancy. It is also known as chloasma or the mask of pregnancy.

Choice A Reason: This is incorrect because hemoconcentration by hypertension is a condition where the blood volume decreases and the blood pressure increases, leading to a higher hemoglobin level. A normal hemoglobin level for a pregnant woman in her second trimester is 10.5 to 14 g/dL. A hemoglobin level of 11 g/dL is within the normal range, not indicative of hemoconcentration.

Choice B Reason: This is incorrect because a multiple gestation pregnancy is a pregnancy with more than one fetus, such as twins or triplets. A multiple gestation pregnancy can cause a lower hemoglobin level due to increased blood volume and increased demand for iron. A hemoglobin level of 11 g/dL is not suggestive of a multiple gestation pregnancy.

Choice C Reason: This is incorrect because greater-than-expected weight gain is not directly related to the hemoglobin level. Weight gain during pregnancy depends on various factors such as pre-pregnancy weight, nutrition, physical activity, and genetics. A hemoglobin level of 11 g/dL does not reflect the weight status of the pregnant client.

Choice D Reason: This is correct because iron-deficiency anemia is a common type of anemia that occurs when the body does not have enough iron to produce enough red blood cells. Iron-deficiency anemia can cause a low hemoglobin level and affect the oxygen delivery to the tissues and the fetus. A hemoglobin level of 11 g/dL may indicate iron-deficiency anemia, especially if the client has other symptoms such as fatigue, weakness, pale skin, or cravings for non-food items. The nurse should confirm the diagnosis with further tests and recommend iron supplements and dietary changes to treat the condition.