What causes watery vaginal discharge with stomach cramps? There are several causes for watery vaginal discharge with stomuch cramps. Few of them are as follows: Possible Causes of Lower Abdominal Pain and Vaginal Discharge 1. Bacterial Vaginosis (BV) 2. Human Papillomavirus (HPV) 3. Pelvic Inflammatory Disease (PID) 4. Trichomoniasis 5. Yeast Infection 6. Ectopic Pregnancy 7. Urethritis 8.Urinary Incontinence Pregnancy hormones can also cause an increase in vaginal discharge, but the discharge is usually clear, mucousy, non-irritant and non-smelly. Any discharge that is discoloured, irritant, bloodstained or smelly should be checked for infection. The two most common vaginal infections are thrush and bacterial vaginosis (BV). Sometimes the infections occur together, so a swab is important in order to make an accurate diagnosis. Since you have not started with your period yet, there is a possibility that you could be pregnant. So it is advisable to get your urine tested for pregnancy. Once your pregnancy is ruled out then the symptoms can be treated accordingly.