Blocked fallopian tubes. Coloured hystero- salpinogram (X-ray) of the reproductive tract of a woman with blocked fallopian tubes, a condition known as hydrosalpinges. At centre is the uterus (womb). The fallopian tubes lead off either side of the top of the uterus. Part of the left fallopian tube (at upper right) shows a large accumulation of fluid (white) and there are smaller dilations in both tubes. Hydrosalpinx is the accumulation of fluid in, and dilation of, a damaged fallopian tube. The damage is a result of pelvic inflammation, most often caused by sexually transmitted diseases. Blocked fallopian tubes are a cause of infertility. Treatment is either with surgical unblocking or removal of the tubes.