I could lend you some money for the STD treatment, if you're hard up.
I got a sexually transmitted disease at the most inconvenient time.
Thank you very much for giving me an STD. It means a lot to me.
A gender sickness is one you catch from *ahem* doing things with those of another or the same gender. You only catch these sicknesses this way, meaning they're sexually transmitted diseases (save yourself some typing and just answer with STD).
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.