Can you get pregnant with positive opk but no ecwm in a given cycle?

See below: Pregnancy is possible from having unprotected sex on any and all days of the menstrual cycle. If you are trying to get pregnant, time sex for a day or so before the expected day of ovulation. If you do not wish to be pregnant, use contraception all the time, every time.

Yes: If you have unprotected intercourse during the time of a positive OPK, you may get pregnant even though you did not see any EWCM. The amount of mucus you see can vary, it can be present even though you don't notice discharge, etc.