Sunita Kulshrestha, MD, FACOG
Sometimes, men and women who conceived one or more children without medical assistance are surprised to find that they are having difficulty conceiving again. This kind of infertility is called secondary infertility, and is defined as the inability to achieve pregnancy after having had a previous pregnancy. The previous pregnancy(ies) may have ended in a miscarriage, abortion or a delivery.
A woman who is under the age of thirty-five, should consult a specialist if she fails to conceive within the first twelve months of trying to conceive. If she is over age thirty-five or if she needed fertility treatment for her first pregnancy, she should seek help if she has not conceived within the first 6 months, or earlier if she or her partner have a known fertility problem.
Secondary infertility is often unexplained. Sometimes, all of the historical factors and testing are normal and there is no identifiable cause of infertility. Although a previous pregnancy implies that at one point in time, egg quality, sperm quality, ovulation, timing of egg-sperm exposure, uterine factors and tubal status (with at least one open tube) were all normal, all of these factors can change. A new partner may have a fertility problem or the female may have previously had her tubes tied or the male may have had a vasectomy.
As a woman ages, the quality of her eggs declines. This decline accelerates after the age of thirty-five and becomes even more rapid after the age of forty. Older women also have eggs that are more likely to have chromosomal abnormalities. Both of these factors can decrease the chance of achieving pregnancy and increase the chance of early miscarriage.
Ovulatory patterns can change with time. Ovulation may be affected by extremes of stress, weight, diet and exercise. Other hormonal abnormalities may develop, including abnormalities of the thyroid gland, an overproduction of the hormone prolactin and exacerbation of polycystic ovary syndrome.
With time, some women develop fibroids (nodules of benign smooth muscle in the uterus) or their existing fibroids enlarge. Women can also have endometrial polyps. Fibroids or polyps may affect fertility if they involve the uterine cavity. If a woman has had any instrumentation or surgery involving the uterus (including a dilation and curettage for a miscarriage or an abortion), or a complicated delivery, she may develop intrauterine adhesions (scar tissue) inside the uterus. The chance of developing scarring in the uterus from any of these procedures, however, is quite low.
Fallopian tubes can become blocked if any inflammatory process involves the pelvis. This primarily occurs in the setting of a pelvic infection (most often chlamydia, gonorrhea or PID (pelvic inflammatory disease). Any surgical procedure in the abdomen or pelvis (including appendectomies, myomectomies (removal of fibroids), and tubal surgery can cause pelvic adhesions (scarring) and these adhesions can cause tubal obstruction. Some women have endometriosis, a progressive condition which can also be a cause of new adhesions in the pelvis.
At the same ages, the male does not have a comparable decline in sperm quality. However, some men as they age can develop varicoceles (dilated blood vessels on the scrotum). This may affect sperm quality. Additionally, sperm is far more sensitive than eggs are to environmental factors and these factors may have changed. Sperm can be affected negatively by certain medications, medical problems, fever, viral illnesses, excessive alcohol consumption and exposure to heat.
A woman who believes she has secondary infertility should consult a physician who is an expert in fertility. Based on the situation, the physician may order tests to include an assessment of ovarian reserve (egg quality), a semen analysis, a hormonal evaluation, and an evaluation of the anatomy (uterus and/or fallopian tubes).
The treatment is based on first identifying the cause and trying to correct it. Possible treatments may be as simple as lifestyle changes (appropriate weight loss, reducing excessive alcohol intake , smoking cessation and/or, stress management).
If testing reveals a hormonal problem, oral medications can be taken to help restore normal hormonal balance and to induce ovulation.
If a woman is of advanced reproductive age or has decreased ovarian reserve (problems with egg quality or response to medications), she may wish to be aggressive and consider IVF (if possible) or use a donor egg and have the embryos transferred into her own uterus. IVF with the use of donor eggs is a highly effective tool to bypass the issue of ovarian aging.
If a woman has tubal disease or has had a tubal ligation in the past, IVF will bypass the need for open tubes. The role of the tube is to collect the eggs and fertilize them. In IVF, the eggs are collected in a procedure called an egg retrieval and fertilization occurs in a dish in the lab. Surgical correction of tubal disease may also be an option in select cases. Fibroids, polyps and intrauterine adhesions can all be managed surgically.
For unexplained infertility, the goal is to improve the efficiency of the conception process. This can be accomplished by 1) Superovulation, a technique to enable the release of more than one egg; 2) Intrauterine insemination in which a higher concentration of sperm is delivered closer to the egg, and 3) In-vitro fertilization (IVF), in which normally fertilized eggs (embryos) are directly replaced into a receptive uterus. Of all these techniques, IVF offers the best success rates.
Conversely, if a problem with the sperm is identified, modalities used may include a urological evaluation and intrauterine inseminations (IUI) if it is a mild problem or in-vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI) for moderate to severe problems. If the male has had a vasectomy then IVF/ICSI can be performed with an NSA (non-surgical testicular sperm aspiration). In IVF/ICSI, only one normal sperm is needed for each egg.
If you have any questions about this or other infertility topics, consult a board-certified reproductive endocrinologist.