Infertility
Discussion
Infertility is all too common. Studies show that approximately 15% of American couples struggle with infertility. Approximately half of these patients seek treatment, and most significantly, about 2/3 cases will conceive with the appropriate treatment.
Infertility is typically defined as a condition in which a healthy couple of childbearing age cannot conceive after more than a year of unprotected sexual intercourse. In women over 35 years of age, the time frame may be shortened to six months. Infertility categories are further subdivided into primary infertility - patients without any prior pregnancies, and secondary infertility - couples who are experiencing infertility after having had previous conceptions.
Infertility causes are varied and complex. During the normal fertility process, a sufficient number of normal sperm must be deposited in the vagina at the appropriate time during the menstrual cycle when sperm can penetrate the cervical mucus, ascend through the uterus and fallopian tubes, and fertilize the egg.
The female must produce a healthy, mature egg that is released from the ovary. After release, the egg must travel down the fallopian tube so that the sperm may fertilize it. The fertilized egg then travels into the uterus and implants in the endometrium (the uterine lining), which will nourish the embryo's further development.
Infertility may be caused by disruption in any of these processes. Egg development and ovulation are under the control of complex hormonal interactions including FSH, LH, estradiol, progesterone, and others. Diseases of the thyroid, adrenal, pituitary, or hypothalamus glands can lead to ovulatory dysfunction. Certain conditions, such as polycystic ovarian syndrome, cause irregular or absent ovulation that leads to infertility.
Multiple Causes
In many infertility cases, patients may experience more than one of the following conditions. Accordingly, a thorough evaluation of both partners is required. Research suggests that infertility cases fall into these categories:
- Abnormal sperm parameters ( male infertility )
- Ovulation and egg quality disorders
- Pelvic adhesions
- Endometriosis
- Fallopian tube disorders
- Uterine anomalies
- Combined male and female causes (multifactorial infertility)
- Unexplained infertility - causative factors in 10-15% of infertile couples cannot be identified
- Most infertility evaluation tests must be done at particular times during the menstrual cycle. Therefore, treatment is seldom initiated until the investigation is complete, for it is necessary to rule out all potential causes.
IVF or other advanced reproductive technologies are not always the treatments of first choice. Other simpler treatments are often effective depending on the causal factors. A complete examination and diagnosis is crucial to determine the cause and timely medical treatment to insure a healthy pregnancy.
Some Causes
- Cervical Factor
- Endometriosis
- Male Factor
- Ovulation Disorders
- PCOS
- Tubal Disease
Once sperm are ejaculated into the vagina they must swim through the cervical mucus, pass the cervix, and enter the uterus. Their final destination is the end of the fallopian tube, where fertilization occurs. Sometimes there are abnormalities in the cervical mucus that can slow, damage, or destroy sperm. Some medications, notably Clomid, can cause a thickening of the mucus making sperm transport difficult.
It is possible that the female, or rarely the male, produces antibodies to the sperm. The body "mistakes" the sperm for invading pathogens and the immune system produces antibodies to destroy them. This is essentially the same reaction seen when the immune system identifies a foreign virus. The male may produce antibodies to his own sperm. There must have been "semen - blood" contact in the past for the body to produce these antibodies. This most often occurs as a result of testicular trauma.
A first line treatment for cervical factor may be intrauterine insemination (IUI). In IUI, specially prepared sperm are inserted directly into the uterus using a small catheter thus avoiding contact with the cervical mucus. If moderate male factor is present, or if there are other abnormalities in the female, IVF may be the best treatment choice.
When poor cervical mucus is the only cause of infertility treatment success rates are typically high.