Hello, Occasional abdominal discomfort is a common pregnancy complaint, and while it may be harmless, it can also be a sign of a serious problem. (Severe or persistent abdominal pain should never be ignored.).Ectopic pregnancy , placental disruption, miscarriage, Urinary tract infection are also causes for pain abdomen . It's better to consult gynaecologist and get her ultrasound addomen done to know the status of fetus.