Which client profile in a prenatal clinic presents the highest risk for HIV infection?

The client profile that presents the highest risk for HIV infection is the adolescent with multiple heterosexual contacts. Adolescents are often considered at higher risk due to several factors, including a lack of consistent use of protection, potential engagement in high-risk behaviors, and biological vulnerabilities associated with younger age, particularly females. Having multiple sexual partners raises the likelihood of exposure to sexually transmitted infections (STIs), including HIV, as each additional partner increases the cumulative risk of exposure.

In contrast, a woman with a single sexual partner may have a lower risk if that partner is known to be HIV-negative. A pregnant client over the age of 35 and a long-term monogamous partner would not inherently indicate a higher likelihood of HIV infection compared to the adolescent with multiple partners, especially if those individuals have been in stable and trusted monogamous relationships. Hence, the highest risk for HIV infection is associated with the adolescent with multiple sexual contacts.