The second day of intercourse on the day of ovulation, abdominal distension and pain may be caused by ovulation pain. When ovulation, the surface of the ovary to break a small opening, and then release the follicular fluid, follicular fluid into the abdominal cavity, stimulating the surrounding peritoneum, will lead to abdominal distension and pain, falling feeling, this is a normal phenomenon, usually last 1-2 days, the abdominal pain will disappear. There is also a possibility that the follicles are not expelled and continue to grow, forming unruptured follicles luteinized, the enlarged follicles may involve the ovarian envelope, thus causing abdominal distension and pain. For those who do ovulation monitoring to guide intercourse, you must go to the hospital after ovulation to do monitoring to see if the follicles are discharged normally. This is because there are some people who will have mature follicles, but the follicles do not break and ovulation is not normal, and in this case they cannot get pregnant.