A pregnant woman undergoes a triple/quadruple screen at 16 to 18 weeks' gestation. What would the nurse suspect if the woman's alpha-fetoprotein (AFP) level is decreased?

Choice A: Hemodilution of pregnancy is a normal physiological phenomenon that occurs when the plasma volume increases more than the red blood cell mass, resulting in a lower hemoglobin concentration. The normal hemoglobin range for pregnant women in the second trimester is 10.5 to 14 g/dL.

Choice B: A multiple gestation pregnancy may cause a higher hemoglobin level due to increased erythropoietin production by the placenta. The normal hemoglobin range for pregnant women with twins in the second trimester is 12 to 16 g/dL.

Choice C: Greater-than-expected weight gain is not related to hemoglobin level. Weight gain during pregnancy depends on various factors such as pre-pregnancy weight, nutrition, activity level, and fetal growth.

Choice D: Iron-deficiency anemia is a condition where the hemoglobin level is below the normal range due to inadequate iron intake or absorption, blood loss, or increased iron demand. The signs and symptoms of iron-deficiency anemia include fatigue, pallor, weakness, shortness of breath, and pica.

Choice A Reason: This is incorrect because cervical insufficiency is a condition where the cervix dilates prematurely and painlessly during pregnancy, leading to preterm delivery or second trimester abortion. It is not a common cause of first trimester abortion, which occurs before 12 weeks of gestation.

Choice B Reason: This is incorrect because uterine fibroids are benign tumors that grow in or on the uterus. They may cause heavy bleeding, pain, or infertility, but they are not a common cause of first trimester abortion. They may increase the risk of miscarriage in later stages of pregnancy.

Choice C Reason: This is correct because fetal genetic abnormalities are the most common cause of first trimester abortion, accounting for up to 70% of cases. Fetal genetic abnormalities are errors in the number or structure of chromosomes that occur during fertilization or cell division. They can cause developmental defects or fetal demise that result in spontaneous abortion.

Choice D Reason: This is incorrect because maternal disease is not a common cause of first trimester abortion. Maternal disease refers to any medical condition that affects the mother's health or pregnancy outcome, such as diabetes, hypertension, thyroid disorders, or infections. Maternal disease may increase the risk of miscarriage in later stages of pregnancy or cause other complications such as preterm labor or preeclampsia.