Ovulation can occur three weeks after child birth. Hence any unprotected relationship beyond three weeks can lead to pregnancy
. It is advisable to use a barrier contraception
and do weekly urine pregnancy test for next three weeks. It is good to use a proper contraception on regular basis now as due to lactation
, the periods may remain irregular or absent for couple of months. In some cases, an emergency intrauterine contraceptive
devise can be inserted. For which, you will need to meet with local Gynaecologist.