General Virtues , that affect you physically or mentally , should be possible through Momentary Creo Rituals.
The usual suggestions would be a Minor Mystery or Minor Breakthrough.
Minor , because you can already increase characteristics.
There are no guidelines for adding Virtues , but would be minimum level 20 for a ritual.
The Fertility Ritual on page 56 in Ancient Magic might be worth a look.
You would have to research a version that worked other than during conception.