by Alan Penzias, MD

Introduction

Infertility is a common but frequently treatable condition. It affects one couple out of six and becomes more common with increasing age. Traditionally, infertility has been defined as one year of unprotected intercourse without conception. However, there are many exceptions to this rule. In order to maximize your chances of becoming pregnant you need to know when it is time to seek help. To be your own best advocate, it is helpful to have a basic knowledge of the comprehensive infertility evaluation before even going to the doctor.

The Basics of Reproduction

The truth about eggs
Every woman is born with all of the eggs that she will ever have. Once the eggs are gone, they can't be replaced. At birth, a girl has approximately one million eggs in her ovaries, but by the time she has her first period only about 400,000 remain. Throughout her reproductive lifetime, a woman will ovulate (release an egg from her ovary) approximately 400 times. This means that roughly 1000 eggs are stimulated to develop each month but only one survives and is released from the ovaries. The other 999 eggs simply wither away.

The hormones that control your ovaries
In order for an egg to be released each month, a woman's body produces and releases the hormones luteinizing hormone (LH) and follicles stimulating hormone (FSH) in a very precise and well-controlled way. Just before the egg is released, the LH rises to a level of three or four times its baseline value. This temporary rise of LH causes the ovary to produce the hormone progesterone. At the same time, the egg, which has grown inside a small pouch of cells on the ovary called a follicle, completes its maturation and is released.

Production of progesterone in the ovary is an important event because progesterone causes a rise in a woman's body temperature. The rise in temperature is small (often less than one degree farenheit) but may be detected using a sensitive thermometer that is available in most pharmacies. This is important because it means that most women have a tool available to help them determine when an egg has been released. It may be helpful to use an online chart such as Pregnancy.org's BBT.

Where do the eggs go?
Once the egg has been released by the ovary it is picked up by the fimbria or "fingers" of the fallopian tube. Although the right fallopian tube commonly picks up an egg from the right ovary and the left fallopian tube commonly picks up an egg from the left ovary, either tube can pick up an egg from either ovary.

The story of fertilization
In order for a woman to become pregnant, the egg must meet sperm inside the fallopian tube. Sperm begin their journey to the fallopian tube in the vagina following ejaculation from sexual intercourse. The sperm are carried into the vagina in a complex liquid called semen. The semen contains proteins and buffers that nourish and protect the sperm.

However, the proteins and buffers present in the semen are not meant to enter a woman's uterus (womb). The cervix (which is the entrance to the uterus) is filled with mucous which acts as a filter. This mucous allows only the sperm to enter and keeps the proteins and buffers of the semen in the vagina. From the cervix, the sperm swim through the uterus and into the fallopian tubes.

When sperm and egg meet in the fallopian tube fertilization occurs. The egg is covered by a protective shell called the zona pellucida. Many thousands of sperm attach to the outside of the zona pellucida but only one ultimately enters. When that single sperm gains access to the egg, the zona pellucida hardens preventing additional sperm from entering. After the sperm and the egg are joined, the new cell is called an embryo.

After fertilization, the embryo begins to divide. It goes from one cell to two cells, then from two cells to four cells, and so on as cell division continues. The embryo also begins to migrate down the fallopian to the uterus. The hormonal changes that occurred prior to the release of the egg from the ovary also affect the lining of the uterus (endometrium). These hormonal changes prepare the uterine lining for the arrival of the embryo.

Detecting pregnancy
Once the embryo arrives in the uterus it sheds its shell and implants into the uterine lining. The newly implanted embryo begins producing a hormone called human chorionic gonadotropin (hCG). The hCG produced by the tiny embryo is first detectable in a woman's bloodstream. As the hCG level rises, some of it passes through a woman's kidneys and ends up in her urine. Testing for hCG in the blood or urine is the basis for blood and urine pregnancy tests.

Who Should Have an Infertility Evaluation?

Every couple who has had one year or more of unprotected intercourse without conceiving should seek help. However, if you have one or more of the following symptoms or conditions you should speak with your doctor and not wait for one full year.

If you are a woman...

• Irregular periods or no periods
• Bleeding between periods
• Pain with sexual intercourse
• History of pelvic infection (other than vaginal yeast infections)
• History of a ruptured appendix or other abdominal surgery
• Age is greater than 35 years old

If you are a man...

• Difficulty achieving or maintaining an erection
• Inability to ejaculate during intercourse
• History of injury to the testicles
• History of infection in the prostate gland, epididymus, or testicles
• History of mumps as a teenager
• History of an undescended testicle

Tests That Couples Can Do at Home

You can begin your fertility tests at home before you even see your doctor. One of the most important questions that your doctor will ask is, "Do you produce an egg every month?" There are two simple tests that you can do at home to help answer this question. Each test will require a trip to your local pharmacy and a modest investment of a few dollars.

Basal Body Temperature Chart
First, you need to purchase a basal body temperature thermometer.  To determine if you are releasing an egg each month, begin taking your temperature with this special sensitive thermometer before you get out of bed each morning. Start taking your temperature on the first day of your period. Chart the results of your temperature on the special graph paper that accompanies your thermometer. Also mark the chart each time you have intercourse. At the end of he month, examine the pattern of your chart. If you notice that the temperature in the morning is lower in the first 10 to 14 days of the month than in the last 10 to 14 days, then it is likely that you are producing an egg. I recommend to my patients that they keep a basal body temperature chart for approximately three months.

Next, look at the chart and see where you have marked the chart for intercourse. Do the marks correspond to the time around the temperature change? If they do, then you are timing intercourse to the release of the egg in an appropriate manner.

Whether or not your temperature chart matches the above description, the information that you have gathered will be very useful to your doctor.

Ovulation Predictor Kits
Another test for ovulation that you can do at home is generally called an ovulation predictor kit. There are many brands to choose from at your local pharmacy. These kits allow you to test your urine for the presence of the hormone LH. Since LH rises temporarily just before ovulation, the indicator stick in the test kit will change color just before the egg is released. I recommend that you begin testing your urine on cycle day 10 (cycle day 1 is the first day of full menstrual flow). Continue testing your urine daily until you detect a color change on the indicator stick.

When your indicator stick changes color, plan to have intercourse that day and/or the following day. Also, keep a record of the cycle day number when the indicator stick changes color. Whether or not the ovulation predictor kit changes color, the information that you have gathered will be very useful to your doctor.

There are two tests that every infertile couple needs to have.