This patient should receive intravenous fluids and narcotic analgesics. She is experiencing a vaso-occlusive pain episode that does not differ greatly from those she typically experiences. Because no reliable physical findings or laboratory markers can objectively establish the vaso-occlusion, the diagnosis of vaso-occlusive pain is based on subjective reports by the patient. She has no signs of acute chest syndrome (ACS) (no fever or hypoxia [oxygen saturation >90% breathing room air]) or other end-organ damage (her creatinine and aminotransferase levels are normal). No randomized studies have been conducted on the effectiveness or harms of standard therapy for vaso-occlusive crisis during pregnancy. Expert opinion recommends this patient should receive the same treatment as nonpregnant patients with sickle cell disease, which includes rest, relaxation, warmth, NSAIDs (which are considered safe before 30 weeks' gestation), oral and intravenous hydration, and narcotic analgesia. Narcotics are safe to use during pregnancy, and she will benefit from hydration, which will theoretically correct any dehydration contributing to the vaso-occlusive episode.

Because neither the patient nor the fetus is displaying symptoms of anemia (significant shortness of breath, dizziness, and chest pain in the mother or fetal distress), transfusion is not indicated. The patient's hemoglobin level is slightly lower now than her prepregnancy baseline; however, neither transfusion nor exchange transfusion is indicated in asymptomatic patients without signs of end-organ damage. Neither has been shown to decrease maternal morbidity or mortality during pregnancy, but both would predispose the patient to iron overload and erythrocyte antibody production. Transfusion would be appropriate to treat symptomatic anemia or signs of end-organ involvement (stroke symptoms, kidney failure, ACS, hepatic involvement).

Hydroxyurea therapy results in decreased mortality in hemoglobin SS sickle cell anemia and is indicated in patients with recurrent painful episodes, ACS, and symptomatic anemia. However, because of its potential teratogenicity, hydroxyurea should not be administered during pregnancy. Proper contraception before hydroxyurea initiation should be discussed with the nonpregnant patient.