Can Periods Be Regulated Without Tablets?

i'm married having letoval past 2 months .......i got periods i have baby soon ..... day13-18 we have sex which day we stop sex .. 20 th age i got married .......... age 23; height 5, weight65, i have irregular periods after getting marriage.........having tablet i get my periods otherwise it wont . but know past 6 months i got my periods regularly