Whether masturbation leads to pregnancy? or it cause any effects in periods. whether a normal blood test and urine test detect pregnancy?

No/no/no: It takes introduction of sperm into the female genital tract to trigger pregnancy. Masturbation does not & does not influence menses. Normal urine tests do not detect pregnancy. If a specific request is made to look for pregnancy urine may have hormones created by a pregnancy. Only blood tests requesting a specific pregnancy test would show one, not regular CBC's.