How early do cramps occur in pregnancy?

Mild cramping in early pregnancy is common and usually harmless. It can start as early as implantation, which occurs about 6-12 days after conception, and can continue throughout the first trimester. These early cramps are often described as a pulling or pinching sensation in the lower abdomen or back. Some women also experience mild cramping during ovulation, which occurs about 14 days before the start of a woman's period.