Final answer:
Renee's risk for having a child with Down syndrome is not significantly higher due to her young age, as the risk increases mainly with maternal age, especially for women age 35 and older.
Step-by-step explanation:
Renee became pregnant several months after her first menarche. Concerning Renee's risk factors associated with her pregnancy, the most relevant choice given the options is that she is at high risk for a spontaneous miscarriage. The risk of having a child with conditions like autism or Down syndrome is not specifically linked to the age at which a woman begins menstruation or becomes pregnant soon afterwards. Regarding Down syndrome, it is well documented that the risk increases significantly for women age 35 and older due to age-related changes that affect the likelihood of the fetus carrying the trisomy 21 genotype. Renee's youth is less commonly associated with an increased risk of having a child with Down syndrome; however, teenage mothers face other potential risks and stressors due to the substantial physical, psychological, and social changes they experience.