You must think very carefully about this. It is not something to be decided in a hurry. Firstly, take the medical advice about any risks to yourself or your unbron child. STDs in pregnancy can harm you and your developing baby; this depends upon which kind of infection you have contracted. Some are less serious but a Caesarian section may be necessary to avoid harm to the baby.
For instance, genital herpes in a pregnant woman is not much of a problem until she gets ready to deliver. Then, if they are active lesions on the genitals they are highly contagious and can infect the baby as it is being born. Therefore, a cesarean section to prevent the transmission of herpes to the newborn. Other STDs present different risks: do take all medical advice seriously and take your decisions carefully. A baby is forever.