During pregnancy, they do some STD testing. What she's had done depends on how far along she is in her pregnancy, what kind of prenatal care she's had, and her doctor, and where she lives.
It is routine to do syphilis testing probably twice during pregnancy. She will likely be tested at least once for gonorrhea and chlamydia, maybe more depending on her risk levels. Some doctors will test for herpes, but that depends heavily on where you live. In Canada, the UK, and some other places, the blood test for herpes is rarely done.
Is she currently pregnant? Recently pregnant?
If she gave you oral sex, the only things you're at risk for is gonorrhea, syphilis and genital hsv1.
Syphilis is uncommon, depending on where you live. You can test for that at 6 weeks. If you develop any sores, see your doctor when that happens.
If she has gonorrhea in her throat, you can get gonorrhea genitally. They may not test her for oral gonorrhea during pregnancy. It's not that common to get it in your throat, but it is possible. You can test for this at about 5 days.
If you don't already have hav1 orally (think cold sores or fever blisters), then you can get it genitally from someone who has it orally when they perform oral sex on you. Even if you've never had a cold sore that you remember, you could still have it. About half the adult population has it, and 90% will never get an outbreak.
If you live in a place that does blood tests, you can ask for a type specific IgG herpes blood test. If it's positive now for hsv1, it's a pre-existing infection. If it's negative now, and positive later, it's a new infection. If she didn't have any sores, chances are low that you'd be infected from this. It's not impossible, though.