Hi, and thanks for your medical question on eHealth forum!
There is no contraindication to sex during pregnancy. The sex drive of females decrease during pregnancy but many still enjoy it a lot. At times in case of a low lying placenta or a highly precious pregnancy achieved by IVF etc, or if the mother has very high BP, then the gynecologists advise against having sex during pregnancy.
Hence even though it is safe to have sex unless specified by gynecologist, it would be wise to have a checkup once before you resume sex. Hope this helps. Take care!