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 Chapter 2.

The Causes of Infertility: Facts and Fallacies

Under exceptional and relentless pressure from all quarters of society to find a cure for infertility and to ensure the well-being of unborn children, medical science has learned a great deal in the past two centuries about human reproduction. For the most part, however, the subject remains a miraculous mystery.

We know many of the basic mechanisms that assist conception, pregnancy, and birth but very few of the fine points regarding how and why these mechanisms function the way they do. In the absence of such knowledge, we operate on theories. By following these theories, we can frequently influence reproductive processes to function the way we want them to. Nevertheless, we seldom know for certain how or why this happens.

At best, any therapy or procedure to facilitate healthy reproduction is imprecise and partial, although it may turn out to be successful. Given the incredible intricacy of the natural reproductive process, there is no such thing as a sure cure when it malfunctions. There are only degrees to which certain problems can be minimized. Most infertility patients assume modern science has more answers than, in fact, it does. Essentially, the best that doctors can offer their infertility patients is informed strategies for navigating their way through largely unknown and unpredictable territory.

Before I go into specific detail about how antibiotic therapy has helped my patients reach their goals, I'd like to set some parameters for that discussion. This chapter will briefly explore what we can say, with some certainty, about what makes a couple infertile. It will also look into the more widespread and damaging misconceptions about infertility I've encountered in talking with my patients. These discussions will establish the basic rationale behind my theory that at least 50 percent of infertility problems are due to bacterial infection.



Definitions of infertility vary greatly even within the medical profession. According to William D. Mosher of the National Centre for Health Statistics, which sets the standard for many medical specialists, a couple is considered infertile "if they are not surgically sterile [that is, rendered sterile by a surgical operation] and have not been able to conceive after a year or more of unprotected intercourse."

I define infertility much more strictly, adding two other conditions. First, I don't consider a couple fertile unless the female partner has been able to carry a baby full term to a live birth. Second, I don't consider a couple fertile unless the baby they produce is healthy-that is, not underdeveloped, colicky, or unusually vulnerable to infectious illnesses.

Many doctors would agree with my first additional condition. Very few would extend their definition of infertility to include my second additional condition. Be that as it may, I believe human reproductive systems-male and female-are wondrously well designed to produce healthy babies. If, instead, a couple produces a baby whose health has been adversely affected by the poor quality or shortened duration of the pregnancy, then I would say without hesitation that the couple has an infertility problem-and one that might easily worsen with time.

For fourteen years, I continued to be a practicing obstetrician despite strong temptations to devote myself entirely to my research and therapy in reproductive health. I retained my role as an obstetrician because I insisted on superintending the final results of that research and therapy. In other words, I felt my mission to reverse a couple's infertility was not complete until I had done everything I could to deliver a healthy baby on or near the date he or she was due to be born. In most of my cases, thankfully, that is what happens.

There is yet another aspect to the basic distinction between fertility and infertility-an aspect to which I referred in Chapter 1. A couple can be either primarily infertile or secondarily infertile. In cases of primary infertility, the couple has never been able to conceive (or, by my definition, produce) a child. In cases of secondary infertility, a couple has managed to conceive-or produce-one or more children in the past but no longer appears capable of doing so (again, after a year or more of unprotected intercourse).

As I will explain in more detail later, many cases of secondary infertility in particular can be attributed to bacterial infection. The logic behind such a pattern is easy to follow. Harmful bacteria first gain entry into the female partner's genital tract at the time of her previous successful conception. The pregnancy resulting from that conception does produce a live baby, but it's quite likely the pregnancy itself is troubled, or the delivery is premature, or the baby is somewhat sickly. By the time the couple tries for another pregnancy, the bacterial infection in the woman's genital tract has spread, and the damage is sufficient to prevent conception or cause a miscarriage.

So far, I have discussed only the infertile couple. I prefer to define fertility or infertility in terms of couples rather than individuals because it is only in the context of the couple that an individual demonstrates his or her fertility or infertility. Someone who is infertile with one partner may be fertile with another partner for reasons medical science may not be able to ascertain.

Of course, there are specifically male-related and female-related infertility problems that can work singly or in tandem to prevent a couple from having a child. In subsequent chapters of this book, I'll examine these major infertility problems in terms of the different therapies used to address them, concentrating mainly on antibiotic treatment. But for now, let me simply identify these problems.

Problems Associated with Infertility. Female (arranged, approximately, from most common to least common):

  • Damaged fallopian tubes - blockage or scarring prevents the egg and sperm from uniting or prevents the united egg and sperm from descending to the uterus for maturation (resulting in an ectopic pregnancy).
  • Abnormal ovulation - the egg-production cycle is not functioning normally due to hormonal deficiencies or imbalances.
  • Pelvic inflammatory disease (PID) - this umbrella term refers to an inflammation of any of the pelvic organs, including the reproductive organs, which can impede their ability to foster conception or support a pregnancy.
  • Endometriosis - the uterine lining (or endometrium) grows outside the uterus, resulting in excess bleeding, blockage, or scarring in the surrounding reproductive structures, which can interfere with conception or pregnancy.
  • Damaged ovaries - scarring prevents proper egg development, fertilization, or release.
  • Hostile cervical mucus - excess acidity or antibodies in the milieu of the cervix (situated between the vagina and the uterus) kills the sperm before they can reach the eggs.
  • Incidental causes - this category includes damage inflicted on any part of the reproductive system by a major abdominal disease, surgery, therapy (such as chemotherapy), tumor (such as fibroid tumor), physical trauma, or drug exposure.

Problems Associated with Infertility. Male (arranged, approximately, from most common to least common):

  • Idiopathic low sperm count (unknown cause of a reduced sperm count) - this is the most commonly observed fertility abnormality in the male, probably caused by an unknown intrauterine factor that adversely affected the development of the testes during the male's embryonic life. Unfortunately, if bacterial cultures are negative, and the hormones are normal, and there is no varicocele, this particular abnormality resists all currently available treatments.
  • Dilated veins around the testicle -this condition, known as varicocele, increases the temperature in the scrotum, which can result in fewer sperm as well as malformed or malfunctioning sperm (that is, poor swimmers).
  • Damaged sperm ducts - blockage or scarring in the sperm ducts (or vas deferens) prevents the sperm from reaching the seminal fluid.
  • Hormone deficiency - there is an insufficient or too-erratic release of the hormones that stimulate sperm production.
  • Impotence - the man is unable to ejaculate inside the vagina due to disease (such as hardening of the arteries, high blood pressure, diabetes, or kidney disease), environmental factors (such as substance abuse or certain medication regimens), or psychological factors (such as performance anxiety or premature ejaculation).
  • Sperm antibodies - in rare cases (for example, among a small fraction of men who have undergone vasectomy reversals), the immune system develops antibodies to the sperm that kill the sperm as soon as they are produced.
  • Incidental causes - this category includes any damage caused by a major abdominal disease, surgery, therapy (such as chemotherapy), tumor, drug exposure, or physical trauma.



I did not single out bacterial infection as a problem leading to infertility in either of the above lists. This is because I'm convinced bacterial infection is a probable underlying or aggravating cause of virtually all these problems. This is not to say a bacterial infection by itself isn't a problem that can lead to infertility-the rest of the book will make this clear.

In a woman, harmful bacteria can give rise to disasters anywhere in the genital tract. They can form adhesions that block or scar the Fallopian tubes and/or the ovaries. They can spur the development of endometriosis or PID. They can offset natural hormone cycles. And they can trigger adverse chemical changes in the cervical mucus.

In a man, the same kinds of harmful bacteria (and, no doubt, others we haven't yet isolated) are similarly far-reaching. They can have a directly negative impact on the volume, morphology, or motility of the sperm wherever the sperm may go. They can also have an indirectly negative impact on sperm production by damaging the testicles. And they can generate adhesions that block or scar the sperm ducts.

Because bacteria are so small, so elusive, and so often asymptomatic, it is extremely difficult to prove the exact nature of their contribution to any given case of infertility. That is why most lists of problems leading to infertility - like the two lists above - are organized according to grosser, more observable phenomena that manifestly distinguish one particular infertility case from another. The special challenge of my career has been not just to accumulate evidence that bacterial infection does, in fact, lie at the root of most infertility problems but to identify and classify the specific bacteria that can be troublesome.

Among all the bacteria that can be found in human reproductive systems, mycoplasma, chlamydia, and certain anaerobic bacteria are potentially harmful. How did I go about determining this? Basically, I approached the problem by creating good-guy versus bad-guy criteria for judging individual bacteria.

Good guys are any bacteria I can determine were present in a woman's genital tract during two successful reproductive processes (that is, from conception to birth on two different occasions). Given such circumstances, I can reasonably assume the bacteria in question are not likely to cause any interference with reproductive health. I insist on two successful reproductive processes to reduce the odds that I may be dealing with a sample from a woman who is, in fact, developing secondary infertility.

Bad guys, by contrast, are any bacteria that appear in the genital tracts of only those women who have had reproductive problems-for example, conception hasn't occurred, or there was a miscarriage, or there was an overly long period of labor. Through meticulous record keeping and repeated studies of cultures from couples whose reproductive histories fit either the former or the latter category, I have been able to identify mypoplasma, chlamydia, and certain anaerobic bacteria as bad guys.

My work is far from over. Besides these three unmasked bad guys, there are hundreds of bacteria for which I'm not (and, to my knowledge, no one else is) yet able to test, including other anaerobes, aerobes, viruses, yeasts, and parasites.

Frankly, anaerobes interest me the most of all these types of bacteria because, like the worst villains in any scenario, they are so charismatic. According to what science has been able to discover to date, not only do anaerobes possess all sorts of capacities to toy unpredictably with the human immune system, but they can also act as co-culprits with other bacteria.

And they are numerous. The ratio between anaerobic bacteria and other bacteria in the average person's genital tract is somewhere between ten to one and twenty to one. This fact more than any other indicates that anaerobic bacteria are the most important ones for me to study in order to isolate any more bad guys. Meanwhile, it's only logical to assume my broad-spectrum antibiotic therapy is killing some of these unknown villains at the same time it is killing the known ones.

When I culture specimens from a couple suffering from infertility and find suspect bacteria in both the male and the female samples, there is always at least one harmful kind of bacterium that both samples have in common. This pattern further corroborates my theory that bacterial infections are sexually transmitted. In most cases of sexual transmission (as I discussed in Chapter 1), the male sperm carries the harmful bacteria into the female genital tract, although it's also possible, to a lesser degree, for a bacterially contaminated woman to infect her bacteria-free male sex partner.

Such officially recognized STDs as gonorrhea and syphilis can spur the infectious activity of other harmful bacteria, like mycoplasma, chlamydia, and certain anaerobes, that are already present but dormant in a person's genital tract. They can also bring these other harmful bacteria with them. During the latter half of the 1980s, chlamydia finally earned widespread acknowledgment as a full-fledged STD. In my opinion, all bacterial infections should be officially recognized as STDs, an issue I'll pursue further in Chapters 5 and 6.

Another way in which bacteria can spread deep into a woman's genital tract (that is, beyond the cervix into the uterus, Fallopian tubes, and ovaries) is through the use of certain types of birth control methods. Intrauterine devices (IUDS) offer the greatest potential risk.

The IUD prevents pregnancy by triggering an inflammation inside the uterus, which makes it impossible for an embryo to implant itself there. The user's normal hormonal cycle continues unchanged, however. The cervix undergoes its monthly estrogen-dominated phase, in which the mucus is favorable for sperm migration, and the sperm have no barrier to prevent them-along with any harmful bacteria they may be carrying from traveling into the woman's upper genital tract. In addition, sperm can penetrate the cervix during the actual menstrual bleeding, and the bleeding time is typically much longer for IUD users. All these factors put together could well explain the marked increase in the rate of PID and other reproductive health problems among IUD users.

Birth control pills are somewhat safer when it comes to avoiding bacterial infection. The pill disrupts the normal hormonal cycle, thus creating a cervical mucus that is sticky and unfavorable to sperm. Nevertheless, pill users are vulnerable to sperm migration and, hence, the spread of bacterial infection beyond the cervix during their menstrual bleeding time.

The ideal birth control method for avoiding the risk of bacterial infection is the condom. When they use a condom, both partners are relatively safe from any contact with foreign body fluids that are bacteria-infected. Failing condom use, the female partner can protect herself by using a barrier-type device (like a diaphragm) for birth control.



No medical condition provokes in its sufferers quite such a complicated mixture of anger, fear, shame, guilt, and hysteria as infertility. It is little wonder, therefore, that so many myths have arisen regarding the causes and cures of infertility-myths that presumably help infertile individuals vent their frustration, shield their embarrassment, assign blame, or simply account for the unaccountable.

Before moving on to examine in more detail what I believe is a woefully under-acknowledged truth about infertility-that is, the major role bacterial infection can play-let me briefly expose the major fallacies associated with infertility, based on what many of my patients have said to me.

The female partner is usually responsible for a couple's infertility.
This is the most prevalent of all myths having to do with infertility. As statistics now stand, the two genders are equally responsible. About 35 percent of infertility cases in America are due to female related problems, about 35 percent are due to male related problems, about 20 percent are due to a combination of male and female related problems, and about 10 percent are inexplicable.

Given my belief that the majority of infertility cases originate in bacterial infection, and given my belief that sperm are the major vehicles for sexually transmitting such infections, I'd be inclined to say the male partner is usually responsible for a couple's infertility. I prefer, however, to treat all cases of infertility as a couple's-and not an individual's-problem and responsibility.

The myth that the female partner is usually responsible for a couple's infertility-which, to my mind, is the most damaging of all infertility myths-can be attributed almost entirely to sexism. For centuries, male-dominated medical science has insisted that women carry the burden of making reproduction work. Not only have men decided that making children is what a woman does, but they've also maintained a willful blindness toward the possibility that their ability to impregnate a woman successfully may be just as fragile as a woman's ability to achieve a successful pregnancy.

Women in developed nations are expected to perform the yearly ritual of going to a gynecologist (usually male) for a checkup. It may be a nuisance, it may be embarrassing, but it's something that has to be done. But how often do you hear men saying to each other, "What did your urologist say the last time you saw him [or her!]?" or "Can you give me the name of a good urologist?" or "I'm considering changing urologists."

I've never overheard such a conversation among men, although I frequently overhear the equivalent among women about their gynecologists. Until I do routinely hear men exchanging such remarks, I won't be satisfied that male partners are assuming the responsibility they should for the reproductive health of the couple.

Psychological problems are a major cause of infertility. 
In fact, psychological problems are seldom a cause of infertility, although they can frequently be a serious effect of infertility. While it is true that cortical events (that is, strong emotions, such as depression) are capable of causing changes in male or female hormonal levels that can, in turn, adversely influence the reproductive system, this situation is very rare. People who have been in prison for years may suffer "psychologically induced" infertility, but under less extreme circumstances, it's highly unlikely such a thing will happen.

Certainly, psychological problems can have a negative impact on spontaneous sexual performance, often resulting in fewer instances of sexual intercourse than the affected man or woman might otherwise have. But the times when they do have sexual intercourse are not at all likely to be compromised by any infertility problems of a psychological nature.

It is not true that "just getting away from it all for a while" enhances a person's-or a couple's-chances of conceiving. What it does enhance are the chances that the couple will engage in sexual intercourse more frequently, which can be beneficial if the couple is otherwise having sexual intercourse only two or three times a month.

It does sometimes happen that couples who are unable to conceive and who finally decide to adopt a child do, in fact, conceive shortly after the adoption. This is not because a change in certain psychological factors has rendered conception possible, however. It is probably because the couple had been undergoing therapy for a long time to reverse infertility, and that therapy finally paid off. Otherwise, as far as science is concerned, it's simply fortuitous.

Infertility is a frequent aftereffect of abortion or rape.
I've had many patients who believe the physical or emotional trauma of an abortion or a rape has rendered them infertile. Some women who have had an abortion believe God is punishing them by not letting them have another baby. Scientifically speaking, there is no evidence that an abortion or a rape will adversely affect one's fertility any more than a miscarriage or an act of consensual intercourse will, unless the abortion or rape involves some gross structural damage to the reproductive system.

Any conception, whether it occurs via rape or consensual intercourse can, of course, spread deleterious bacteria through the woman's genital tract. In the case of an abortion, especially if the woman has never given birth to a child or has previously given birth to only one child, secondary infertility may be the result of such an infection, but it will remain undetected until a subsequent attempt at pregnancy. The chances are high that any such condition can be reversed with the help of antibiotic therapy at that later date. In the case of rape, the victim may have been infected with bacteria-laden sperm, but this, too, can be treated.

Infertility has a negative impact on sexual performance or enjoyment.
There is no reason that an asymptomatic infertility condition should have any effect on one's sexual performance or enjoyment, including a woman's ability to have an orgasm or a man's ability to ejaculate. In cases where an infection in the male or female partner's genital tract is painful, sexual intercourse will, of course, be less enjoyable. For the partner who experiences this symptom, sexual relations may be merely a bit irritating or altogether too painful to endure. If one or both partners suffer anxiety over infertility, then sexual relations may also be less pleasurable, but this is not due to any physical cause.

If a person is infertile, he or she can sense it.
Most cases of infertility are asymptomatic. In other words, there is no way the infertile individual would be able physically to sense his or her infertility. The same situation applies to an infertile couple.

One way to overcome infertility is to have frequent intercourse.
Assuming a couple has sexual intercourse the "average" number of times-twice a week (or three times one week and one time the next week)-then a pregnancy should occur within a year. If not, then the couple is most likely suffering from an infertility problem or combination of problems, and such a problem or combination of problems is not likely to be overcome by having sexual intercourse more frequently. For possible exceptions, see below.

Carefully timing sexual intercourse to occur during the right time of the month is crucial to overcoming infertility.
Again, if a couple has sexual intercourse roughly two times a week and no specific infertility problems are involved, then coordinating sexual activity precisely with the optimum time in the female partner's monthly menstrual cycle doesn't really boost the chances of conceiving. If they're having sexual relations only twice a month, then it does make sense to time intercourse to coincide with the female partner's optimum days for conception each month.

Another situation in which timing may matter is when age is a factor-that is, when the female partner is over thirty-six. A couple perceiving a biological deadline may not want to wait as long as a year for a conception to occur. Instead, they may attempt to maximize their chances each month by timing sexual intercourse to occur on the best days. In cases where several factors come into play-for example, a low sperm count, a female partner over thirty-six and a history of bacterial infections in either partner-then timing can make a critical difference.

Infertility can be inherited.
Infertility per se cannot be inherited, except in extremely rare cases involving structural or hormonal problems that are genetic in nature. In these cases, the problems are almost always manifestly apparent to the person who has them.

Unlike many of my colleagues, however, I do believe there is one respect in which this myth is not far from the truth. My experience with numerous patients has convinced me that harmful bacteria can be transmitted during the birthing process from a mother's reproductive system to her child's reproductive system. And abnormalities in a pregnancy (which will be clarified later) can make the offspring even more vulnerable to contamination in his or her genital tract. But this is a matter to be explored in the next chapter, where I discuss how I diagnose and treat specific cases in my practice.

To Chapter 3: How Antibiotic Therapy Works to Ensure Fertility