A hysterosalpingogram (HSG) is a test done to determine the potential of female fertility and shows if and where the fallopian tubes are blocked.
During a hysterosalpingogram, x-ray pictures are taken as contrast dye is slowly injected through a thin tube or catheter through the cervical opening into the uterus and fallopian tubes. The pictures can show problems such as an injury or abnormal structure of the uterus or fallopian tubes, or a blockage that would prevent an egg from moving through the fallopian tube to the uterus. A blockage also could prevent sperm from moving into a fallopian tube and joining (fertilizing) an egg. A hysterosalpingogram may also find problems on the inside of the uterus that prevent a fertilized egg from attaching (implanting) to the uterine wall.
If a permanent birth control device such as Essure has been placed, a modified HSG can also be performed to verify the positioning and check proper function of the device.