The fallopian tubes are conduits for moving ovulated eggs from the ovaries to the uterus, where, if fertilized, they implant and grow for 9 months. Many diseases can cause scarring of the fallopian tubes, decreasing the chances of pregnancy and increasing the possibility of ectopic pregnancy, pregnancy that attaches to the inside of the tubes instead of the uterus. Scar tissue, also called adhesions, in the tubes can also lead to swollen, dilated tubes, called hydrosalpinx.
Infertility
Sexually transmitted diseases such as chlamydia and gonorrhea can cause infection within the tubes known as pelvic inflammatory disease (PID). Approximately 10 percent of women who have PID will have infertility issues from blocked or partially blocked tubes, according to the Center for Disease Control (CDC). An egg can't pass the blockage to be fertilized and implant. A partially blocked tube may lead to implantation of the fertilized egg in the fallopian tube, an ectopic pregnancy. Scarring leading to infertility can also be caused by endometriosis, tissue that normally lines the lines the uterus but migrates out and invades the fallopian tubes and other parts of the pelvis.
Hydrosalpinx
Scarring in the tube, especially near the end of the tube closest to the ovary, can lead to large, dilated tortuous tubes filled with infected, debris filled fluid. A swollen tube is called a hydrosalpinx. According to a meta-analysis of 11 different studies involving 6,700 treatment cycles reported by the American Society for Reproductive Medicine in the November 2008 issue of "Fertility and Sterility", women who have hydrosalpinx have a pregnancy rate 49 percent lower than women with tubal damage but no hydrosalpinges. Hydrosalpinx are filled with infected fluid that may be chemically toxic to embryos and interfere with implantation.
Ectopic Pregnancy
Scar tissue in the fallopian tube can keep the fertilized egg from reaching the uterus. The embryo instead implants in the fallopian tube, but the tube isn't big enough for an embryo to grow for 9 months. If the tube ruptures before the pregnancy is surgically removed or chemically dissolved, a woman can bleed to death quickly. Ruptured ectopic pregnancy is a medical emergency. According to the Mayo Clinic, 50 percent of women who have ectopic pregnancies have tubal damage, either from previous infection or from endometriosis.
Pain
Scar tissue in or around the fallopian tubes can cause the tubes to twist or to stick to other structures in the pelvis, causing pelvic pain that becomes chronic over time, according to the CDC.
