With a cervical factor, infertility is caused by a problems with the cervix, which is the base of the uterus. Infertility can also be due to a problem with one or both fallopian tubes (tubal factor).
Cervical Factor Infertility
The cervix is an extension of the lower part of the uterus, and it protrudes into the vagina. Sperm should be able to swim in the cervical mucus traveling from vagina through the cervix and the uterus. The glands that line the cervix produces cervical mucus, which offers nutritional support for the sperm. One cause of infertility involves sticky or thick cervical mucus, which will interfere with sperm transport. Estrogen levels increase right before ovulation, which causes increased mucus production.
Another cause of infertility is anti-sperm antibodies. Some women produce anti-sperm antibodies, which make the female’s body mistake the sperm for invading organisms. These antibodies kill the sperm, so it cannot fertilize the egg. Cervical factor infertility is also caused from medications, congenital anomalies, cervical or uterus surgery, and many unexplained factors.
Diagnosing cervical factor infertility involves a comprehensive medical history and physical examination. Transvaginal ultrasound and mock embryo transfer are both methods for assessing cervical problems. Cervical factor infertility can be successful treated with intrauterine insemination (IUI). With this procedure, sperm are inserted into the uterus through a small catheter that passes up the cervical opening.
Tubal Factor Infertility
The fallopian tubes are passageways between the ovaries and the uterus. These structures lie on each side of the uterus. When ovulation occurs, the egg is released by an ovarian follicle and picked up by the fimbriae (finger-like projections at the end of the fallopian tube). The egg is fertilized in the tube, becomes an embryo, and then progresses on to the uterus. Once the embryo makes it to the uterus, it implants into the lining (endometrium) after a few days.
The test used to diagnose tubal factor infertility is the hysterosalpingogram (HSG). With the HSG, dye is injected into the uterus and tubes. An x-ray is used to see if or not the dye can pass through the tubes. If the fallopian tubes are blocked or damaged, the sperm and egg cannot find each other.
Blocked fallopian tubes will prevent normal conception, so the fertility specialist may recommend in vitro fertilization (IVF). The ovaries can be stimulated to produce multiple eggs, which will be retrieved using a simple technique under anesthesia. In the laboratory, the eggs are fertilized with the partner’s sperm, and the resulting embryos are transported to the uterus using a small catheter.
At the end of the tube is blocked, it cannot pick up the egg. This causes the tube to collect with fluid and dilate, which is called hydrosalpinx. Fluid inside the tube will decrease chances of pregnancy with IVF by more than 50%. When hydrosalpinx is found, the doctor may recommend using a surgical procedure to remove the tube or block it. In addition, a partially open tube could lead to an ectopic pregnancy, where the fertilized embryo implants into the tubal wall.
When a woman has had a tubal ligation, it creates a definite tubal factor infertility. Women who wish to have children after a tubal ligation must undergo a procedure called tubal reanastomosis. This involves surgery to rejoin the tubes. In event reanastomosis is unsuccessful, or if the likelihood of pregnancy is low, the fertility specialist may recommend in vitro fertilization.