A nurse is providing instruction to a client about diagnostic tests during their first prenatal visit at 12 weeks of gestation. Which of the following diagnostic tests should the nurse include in the teaching?

Choice A rationale Group B Streptococcus (GBS) screening is typically performed much later in pregnancy, usually between 35 and 37 weeks of gestation. This screening is crucial for identifying carriers and administering prophylactic antibiotics during labor to prevent vertical transmission to the newborn, which can cause severe infections like sepsis or meningitis. Choice B rationale Human immunodeficiency virus (HIV) screening is a standard diagnostic test offered to all pregnant clients during their first prenatal visit, typically around 12 weeks of gestation. Early detection allows for timely interventions, such as antiretroviral therapy, to reduce the risk of mother-to-child transmission and improve maternal health outcomes. Choice C rationale Chorionic villus sampling (CVS) is an invasive diagnostic procedure performed earlier in pregnancy, usually between 10 and 13 weeks of gestation, but it is not a routine screening test. It is typically offered to clients at high risk for genetic disorders due to family history, advanced maternal age, or abnormal prenatal screening results. Choice D rationale Cervical cone biopsy is a diagnostic and therapeutic procedure used to remove a cone-shaped piece of tissue from the cervix, typically to evaluate or treat abnormal cervical cells. It is not a routine diagnostic test during a normal prenatal visit and is usually performed prior to pregnancy or if there are specific gynecological concerns.