Which of the following is a bacterial infection that spreads through any form of unprotected sex and by skin contact? Typically, it has stages of increasingly serious symptoms. If untreated, it may affect the heart, eyes, and brain. It can be treated with antibiotics.

Choice A: Decreased production of erythrocytes

This is not the primary cause of iron deficiency anemia during pregnancy. While erythrocyte production may be affected in certain conditions, it is not directly linked to iron deficiency anemia in pregnancy¹.

Choice B: Inadequate intake of iron

This is the correct answer. During pregnancy, the body needs more iron to make hemoglobin for the increased volume of blood. If the intake of iron is not sufficient, it could lead to iron deficiency anemia¹.

Choice C: Dilution of hemoglobin concentration

While it's true that the blood volume increases during pregnancy, leading to a relative dilution of hemoglobin, this is not the primary cause of iron deficiency anemia. The main issue is the lack of sufficient iron intake¹.

Choice D: The fetus establishing iron stores

While the fetus does require iron, which it gets from the mother, this is not the primary cause of iron deficiency anemia during pregnancy. The main issue is still the mother's inadequate intake of iron¹.

Choice A reason: Gonorrhea is incorrect because it is not the infection described in the question. It is a bacterial infection that spreads through any form of unprotected sex, but it does not have stages of symptoms or affect the heart, eyes, and brain. It can cause pain, discharge, and inflammation in the genitals, anus, or throat. It can be treated with antibiotics.

Choice B reason: Syphilis is correct because it is the infection described in the question. It is a bacterial infection that spreads through any form of unprotected sex and by skin contact. It has stages of symptoms, such as sores, rashes, fever, and fatigue. If untreated, it can affect the heart, eyes, and brain, causing serious complications. It can be treated with antibiotics.

Choice C reason: Chlamydia is incorrect because it is not the infection described in the question. It is a bacterial infection that spreads through any form of unprotected sex, but it does not have stages of symptoms or affect the heart, eyes, and brain. It often causes no symptoms, but it can cause pain, discharge, and bleeding in the genitals or rectum. It can be treated with antibiotics.

Choice D reason: Trichomoniasis is incorrect because it is not the infection described in the question. It is a parasitic infection that spreads through any form of unprotected sex, but it does not have stages of symptoms or affect the heart, eyes, and brain. It can cause itching, burning, and odor in the genitals. It can be treated with antiparasitic drugs.