If a patient has a high risk of Down syndrome (>1 in 150), what is the next step in management?

When a patient has a high risk of Down syndrome, indicated by a screening result of greater than 1 in 150, the most appropriate next step in management is to refer for further investigations such as chorionic villus sampling (CVS) or amniocentesis. These tests are designed to provide a definitive diagnosis by analyzing fetal cells for chromosomal abnormalities, including those associated with Down syndrome.

Choosing to conduct further investigations is crucial because it allows for a more accurate assessment of the risk of Down syndrome, enabling the expectant parents to make informed decisions regarding their pregnancy. Chorionic villus sampling is typically performed between 10 to 13 weeks of gestation, while amniocentesis can be conducted later in the pregnancy. Both procedures carry a small risk of miscarriage but are essential for clarifying the diagnosis when the risk assessment indicates a need for additional evaluation.

The other options provided do not address the immediate need for diagnostic confirmation in a high-risk situation. Immediate delivery is not warranted as the presence of a high-risk screening result does not necessitate termination or premature delivery without a confirmed diagnosis. Starting prenatal vitamins is generally recommended early in a pregnancy but does not specifically pertain to the management of a high risk for Down syndrome. Finally