If you are wondering this thought, you are not alone. While half of couples achieve a pregnancy by three months without using a contraceptive method, one out of eight couples fails to conceive a successful pregnancy despite trying for an entire year. These couples are advised to seek medical attention to search for a reason for their troubles. In most cases there are treatments available that can increase the couple’s chances for a successful pregnancy. To understand why fertility tests are done, it is best to review the basic components of human conception.
A woman is born with as many eggs as she will ever have. After puberty one egg typically will ripen each month. Only ripened eggs can fertilize. Every day a number of eggs wither away rather than ripen. Eventually a woman runs low on eggs. When the reserve of eggs is nearing exhaustion, the ratio of “good” eggs is outnumbered by “bad” eggs that don’t make viable babies. The ovary releases a matured egg in a process called ovulation, which typically occurs 14 days before her next period is due. Menstrual cycle lengths of 25-34 days are considered normal.
Sperm are produced in the male’s testicles beginning at puberty. New sperm are constantly being made throughout the man’s life. The mature sperm are stored in the epididymis (a tube near the testicle) until ejaculation, when they mix with glandular secretions to form what is semen. Normally there are at least 20 million moving sperm in the ejaculate. The sperm in the epididymis are usually sufficiently replenished around 24 hours after ejaculation.
A woman’s cervical mucus should get more plentiful a few days before ovulation so that it can help direct the ejaculated sperm to swim into the uterus. The sperm in the cervical mucus lose a bit of their vigor after 48 hours so timing of intercourse is important. The guy’s forward swimming soldiers travel up both fallopian tubes where they await the arrival of the woman’s egg. The ovulated egg is picked up by the end of one of the fallopian tubes. For the process to work, a single sperm cell must penetrate the shell around the egg within 24 hours after ovulation. Next the DNA (the genetic material contained within the chromosomes) from the sperm enters the egg nucleus. Now the full double set of genes are together. Implantation.
The fertilized egg must divide into many cells as it develops. Typically this embryo reaches the interior cavity of the uterus four days after fertilization. The lining of the uterus has been made into “fertile ground” by two ovarian hormones (estrogen and progesterone). If the embryo has the stamina to implant in the lining of the uterus and keep growing, then the woman misses her period and a positive pregnancy test is detectable by 14 days after ovulation.What can go wrong and how can it be corrected?
Obviously there are many steps in the process where things can go awry. At least 5 % of men in the population have insufficient numbers of moving sperm in their ejaculate. Semen can lack sperm if there is an obstruction in the tube that transports the sperm from the testicle to the prostate. Most of the time low sperm concentrations are due to a problem in the manufacturing of the sperm. Excessive heat to the testes from a scrotal varicose vein may sometimes be the culprit. Often no clear cause is found. Men should avoid the use of anabolic steroids, smoking, and excessive alcohol consumption. When sperm parameters are only mildly impaired, pregnancy rates are improved by intrauterine insemination (IUI) — which is simply the placement of the washed semen into the uterus, giving them a head start toward the egg. The more severe sperm deficiencies require a more labor-intensive process called in-vitro fertilization (IVF). For IVF, eggs are retrieved directly from the woman’s ovaries so that an individual sperm can be injected straight in to each egg to achieve fertilization. In the most severe cases, where no sperm can be found even with a biopsy of the testicle, donor sperm from a sperm bank can be inseminated into the uterus.
The most common fertility problem encountered in women
is inconsistent ripening of the egg. Ovulation can be induced with the correct use of various fertility medications (pills and or injections). If a woman has nearly run out of eggs then her chance to carry a pregnancy is much improved if she uses donated eggs. If the fallopian tubes are blocked, then sperm and egg are unable to meet. Treatments to overcome this problem include surgical correction of the tubes or the use of IVF. There are conditions that can cause more subtle defects in the ability of the egg to reach the tube. Scar tissue surrounding the ovary is one such condition, and endometriosis – which can set up a hostile environment to the ovulated egg – is another. Minimally invasive surgery such as laparoscopy is sometimes used to search for and to eradicate endometriosis or scar tissue, especially in women who have pelvic pain, worsening menstrual cramps, or ovarian endometriotic cysts.
Armed with this basic knowledge of human reproduction, potential parents who are having trouble making a baby can better negotiate through the medical evaluation and treatment of infertility to achieve the dream of building their family. For more information, please call South Jersey Fertility Center at (856) 596-2233 or visit www.sjfert.com.
As seen in Camden County Woman and Burlington County Woman