Fertility

Female Fertility

The inability to conceive a child can be stressful and frustrating, and although infertility affects almost 6.7 million couples in the United States (a staggering 10-11% of reproductive aged couples in the United States),12 it is highly treatable in many cases. 

The highly specialized field of female fertility involves a wide range of medical, environmental, and lifestyle causes which also includes many very specific risk factors.3 However, now that the genetic causes of female infertility are more commonly diagnosed, and several female infertility treatments are readily available, couples having difficulty conceiving, or carrying to term, can often have success with the use of fertility medications.4

Infertility is defined as a couples' inability to conceive a child even though they've had frequent, unprotected sexual intercourse for a year or longer.5 According to the Mayo Clinic, infertility results from male infertility factors about one-third of the time, female infertility factors about one-third of the time, and unknown or a combination of male and female factors about one-third of the time.4

Female Infertility Symptoms

As would be expected the main symptom of infertility (male or female) is the inability to conceive. However, if you are a woman age 30 or older, who has had unprotected intercourse for six months to year without getting pregnant, you should have an infertility evaluation. Other symptoms may include:6

  • an absent menstrual cycle indicating lack of ovulation an irregular menstrual cycle that's too long (35 days or more) or too short (less than 21 days)
  • an abnormal menstrual cycle that's heavier or lighter than usual
  • history of irregular or painful periods, or pelvic inflammatory disease
  • repeated miscarriages
  • prior cancer treatment
  • endometriosis

Most physicians agree that when you seek medical attention should be age-dependent, and that if you’re:7

  • in your early 30s or younger, try to get pregnant for at least a year
  • between 35 and 40, six months of trying
  • if you're older than 40, a couple of months

Understanding Female Infertility

Prior to discussing the causes of infertility, let's examine the complex process of fertility from the female perspective. This process begins with functioning ovaries that produce and release a healthy egg (ovulation), and regular sexual intercourse during your fertile time. Then for pregnancy to occur, every step in the complex human reproduction process has to be just right:8

  • one of the two ovaries releases a mature egg
  • the egg is picked up by the fallopian tube
  • sperm swim up the cervix, through the uterus and into the fallopian tube to reach the egg for fertilization
  • the fertilized egg travels down the fallopian tube to the uterus
  • the fertilized egg implants and grows within the uterus

Female Infertility Causes

As you can imagine a number of female factors can disrupt any step of this process, and female infertility may be caused by one or more disruptive factors. More specifically, infertility causes are traditionally grouped into categories among which are: ovulation disorders; damage to fallopian tubes (tubal infertility); endometriosis; and uterine or cervical causes.9101112

Ovulation disorders represent ovulating that is infrequent or non-existent, and can be caused by flaws in the regulation of reproductive hormones, the hypothalamus, the pituitary gland, or by problems within the ovary itself. Ovulation disorders account for infertility in approximately 25% of infertile couples,13 and includes:13

  • Polycystic ovary syndrome (PCOS) – complex changes occur in the hypothalamus, pituitary gland and ovaries, resulting in a hormone imbalance, which affects ovulation; most common cause of female infertility.
  • Hypothalamic dysfunction – disruption in the release of the two pituitary gland produced hormones responsible for stimulating ovulation each month, i.e., follicle-stimulating hormone (FSH) and luteinizing hormone (LH); main sign of this problem is irregular or absent periods.
  • Premature ovarian insufficiency – a disorder usually caused by an autoimmune response wherein your body mistakenly attacks ovarian tissues or by the premature loss of eggs from your ovaries due to genetic problems or environmental complications like chemotherapy.
  • Excessive prolactin – rarely the pituitary gland (or medication contraindications) can induce the excessive production of prolactin (hyperprolactinemia), which reduces estrogen production and may cause infertility.
  • Damage to fallopian tubes (tubal infertility) or blockage, prevents sperm from getting to the uterus and egg for fertilization, causes include:
  • Pelvic inflammatory disease – an infection of the uterus and fallopian tubes due to chlamydia, gonorrhea, or other sexually transmitted infections.
  • Previous surgery in the abdomen or pelvis, including surgery for ectopic pregnancy – a fertilized egg becomes implanted and starts to develop within a fallopian tube instead of the uterus.
  • Pelvic tuberculosis – a major cause of tubal infertility worldwide, although uncommon in the United States.

Endometriosis – occurs when extra tissue growth occurs within the uterus requiring surgical removal which can cause scarring that may obstruct the tube and can:

  • Prevent egg fertilization
  • Affect the lining of the uterus, disrupting implantation of the fertilized egg
  • Affect fertility indirectly by damaging the sperm or egg

Uterine or cervical causes – can impact fertility by interfering with egg implantation or increasing the likelihood of a miscarriage through:

  • Benign polyps or tumors (fibroids or myomas) are common in the uterus.14
  • Endometriosis scarring or inflammation.15
  • Uterine abnormalities present from birth, such as an abnormally shaped uterus.14
  • Cervical stenosis, a cervical narrowing, can be caused by an inherited malformation or damage to the cervix.1416
  • Cervix inability to produce the best type of mucus to allow the sperm to travel through the cervix into the uterus.1517
  • Unexplained infertility – possible combinations of minor factors in both partners underlie unexplained fertility problems. Although it's frustrating to not get a specific answer, this problem may correct itself with time.15

Proper Diagnosis of Female Infertility

Infertility evaluations are usually scheduled with a reproductive endocrinologist, a specialist in treating conception disorders. In preparation for your appointment you should:18

  • Chart your menstrual cycles and associated symptoms for a few months.
  • Make a list of any medications, vitamins, herbs or other supplements you take.
  • Bring previous medical records.
  • Think about what questions you'll ask. List the most important questions first in case time runs out.
  • Note basic information like how long have you been trying to become pregnant; intercourse frequency; gynecological conditions; number of days between menstrual cycle start dates; and types of premenstrual symptoms.

In most cases, both partners are tested and may undergo a number of varied and gender specific tests to determine the cause of infertility. Female fertility tests may include:19

  • Ovulation testing with an at-home OTC ovulation a test detects the surge in luteinizing hormone (LH) that occurs before ovulation. Doctors perform blood tests for prolactin and progesterone (a hormone produced after ovulation).
  • Hysterosalpingography (his-tur-o-sal-ping-GOG-ruh-fee) is an interuterine X-ray which looks for abnormalities.
  • Ovarian reserve testing helps determine the quality and quantity of eggs available for ovulation.
  • Other hormone testing checks levels of ovulatory hormones as well as thyroid and pituitary hormones that control reproductive processes.
  • Imaging ultrasound tests look for uterine or fallopian tube disease.
  • Laparoscopy is a minimally invasive, small incision beneath your navel for inserting a thin viewing device to examine your fallopian tubes, ovaries and uterus. May identify endometriosis, scarring, blockages or irregularities of the fallopian tubes, and problems with the ovaries and uterus.
  • Genetic testing for fertility causing genetic disorders.

The Clinical Rational For Treating Female Infertility

The cause, your age, how long you've been infertile, and your personal preferences all largely determine how your infertility is treated. The complexities of infertility constitute significant time, psychological, physical, and financial commitments. Although some women need just one or two therapies to restore fertility, it's possible that several different types of treatment may be needed before you're able to conceive.

Treatments attempt to restore fertility in three primary ways:2021222324252627

  • Although rarely used now due to the overwhelming success rates of other fertility treatments, several surgical procedures can correct problems or otherwise improve female fertility, including laparoscopic or hysteroscopic surgery, tubal ligation reversal surgery (microscopic), and basic tubal surgeries.
  • The most commonly used method is reproductive assistance intrauterine insemination (IUI), and assisted reproductive technology also known as in vitro fertilization (IVF).
  • The primary treatment for women who are infertile due to ovulation disorders is fertility restoration, or stimulating ovulation with fertility drugs which regulate or induce ovulation. In general, they work like the natural hormones, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), to trigger ovulation. They are also used in women who ovulate to try to stimulate a better egg or an extra egg or eggs.

Male Fertility

The inability to conceive a child can be stressful and frustrating, and although infertility affects almost 6.7 million couples in the United States (a staggering 10-11% of reproductive aged couples in the United States),128 it is highly treatable in many cases. 

The highly specialized field of male fertility involves a wide range of medical, environmental, and lifestyle causes which also includes many very specific risk factors. However, now that the genetic causes of male infertility are more commonly diagnosed, and several male infertility treatments are readily available, couples having difficulty conceiving, or carrying to term, can often have success with the use of fertility medications.29

Male Infertility Symptoms

As would be expected the main symptom of infertility (male or female) is the inability to conceive. Although there may be no other obvious symptoms, underlying problems such as hormonal imbalances, inherited disorders, or certain medical conditions in which the passage of sperm may result in telltale signs which include:3031

  • Ejaculation difficulty
  • Difficulty maintaining an erection (erectile dysfunction)
  • Pain, swelling, or a lump in the testicle area
  • Decreased facial or body hair or other signs of a chromosomal or hormonal abnormality
  • A lower than normal sperm count
  • A history of testicle, prostate, or sexual problems
  • Groin, testicle, penis, or scrotum surgery
  • Specific, and/or repeated trauma to the groin area

Understanding Male Infertility

Prior to discussing the causes of infertility, let's examine the complex process of fertility from the male perspective. This process begins with properly functioning testicles,32 and the ability to produce testosterone as well as the supporting hormones which trigger and maintain sperm production.33 Once produced, delicate tubes transport sperm cells until they mix with semen and are ejaculated out of the penis.34 If the number of sperm in your semen (sperm count) is low, it decreases fertilization odds.35 Most authorities consider low sperm count to be fewer than 15 million sperm per milliliter of semen, or fewer than 39 million per ejaculate.36 In addition to production and volume, sperm cells must be shaped correctly and able to move freely.3735 If the movement (motility) and shape (morphology) of your sperm is abnormal, it will experience difficulty reaching and penetrating the egg to complete fertilization.35

Male Infertility Causes

Male infertility is most often due to three factors: 1) blockages that prevent the delivery of sperm; 2) low sperm count; and 3) misshapen or immobile sperm cells. However, because the process is so delicate, many related factors can also contribute to the overall problem including injuries, poor lifestyle habits, illnesses, and chronic health problems. More specifically, infertility causes are traditionally grouped into medical, environmental, and lifestyle categories among which are:38163940414243449454647

Medical Causes:

  • Hormone imbalances can result from disorders of the testicles or an abnormality affecting the hypothalamus, pituitary, thyroid and adrenal glands causing a deficiency in testosterone production.48
  • Sperm duct defects - tubes that carry sperm can be damaged by illness or injury. Other transport problems include a blockage near the epididymis, cystic fibrosis, and genetic conditions which cause males to be born without sperm ducts.49
  • Bacterial and viral infections can cause scarring that blocks the passage of sperm, and may result from STDs including chlamydia and gonorrhea, or from inflammation prostatitis and mumps orchitis.50
  • Chromosome defects can cause abnormal development of the male reproductive organs and infertility. They include Klinefelter's, Kallmann's, Young's, and Kartagener syndromes.51
  • Antibodies that attack sperm are immune system cells that mistake sperm for harmful invaders and attempt to eliminate them.52
  • Tumors can affect the male reproductive organs or the glands that release hormones related to reproduction.535049
  • Undescended testicles49
  • Problems with sexual intercourse such as painful intercourse, anatomical abnormalities like hypospadias, difficulty maintaining an erection (erectile dysfunction), premature ejaculation, and psychological or relationship problems.54
  • Certain medications which include anabolic steroids, testosterone replacement therapy, chemotherapy, and certain antifungal medications.55
  • Varicocele - a swelling of the veins that drain the testicle, and may prevent normal testicular cooling, resulting in sperm abnormalities and lowered sperm count.56
  • Ejaculation issues - retrograde ejaculation occurs when semen enters the bladder during orgasm instead of emerging out the tip of the penis. Various health conditions can cause retrograde ejaculation including diabetes, spinal injuries, medications, and surgery of the bladder, prostate or urethra. Some men with spinal cord injuries or certain diseases can't ejaculate semen, even though they still produce sperm.49

Environmental Causes:55

  • Radiation or X-ray exposure can permanently reduce sperm production.
  • Excessive heat from continuous hot tub, sauna, or laptop computer usage.
  • Industrial chemical exposure to pesticides, herbicides, toluene, xylene, paint and varnish products, organic solvents, and benzenes.
  • Heavy metal exposure to lead or other heavy metals.

Health, Lifestyle, and Other Risk Factors:55

  • Prolonged bicycle seat pressure
  • Excessive amounts of body fat and obesity (a BMI of 30 or greater).
  • Tobacco smoking and secondhand smoke exposure.5755
  • Emotional stress can interfere with sperm producing hormone production.55
  • Recreational drug use including anabolic steroids, cocaine, and marijuana can have temporarily adverse effects on sperm production.5755
  • Alcohol use and liver disease caused by excessive drinking can lower testosterone levels, cause erectile dysfunction, and decrease sperm production.5755
  • Certain occupations can increase your risk of infertility, including those associated with toxins, extended use of computers or video display monitors, shift work, and work-related stress.55

Proper Diagnosis of Male Infertility

The first step in addressing suspected infertility is to visit your family doctor or a general practitioner, after which you will likely be referred to a fertility specialist who will perform an extensive evaluation, which includes a lot of routine present and past medical information.58 Although the scheduling receptionist may or may not request that you to do so, you can gather much of the necessary data prior to your visit, such as:58

Any atypical symptoms you're experiencing, including any that may seem unrelated to infertility.
All surgeries and dates, whether unrelated or directly related, e.g., a vasectomy or vasectomy reversal.
Key personal information, including all recent major life changing events, and stressors.
Investigate your family history for fertility problems, especially male relatives (grandfather, father, and brothers).
A list of all medications, vitamins and supplements including herbs, remedies, and topicals (specialty shampoos, lotions, etc.) that you currently take.

In most cases, both partners are tested and may undergo a number of varied and gender specific tests to determine the cause of infertility. Such infertility tests can be expensive and may not be covered by insurance, so find out what your medical plan covers ahead of time. Testing usually involves a general physical examination of your genitals,59 followed by questions that could affect fertility about:59 surgeries and injuries; chronic health problems and illnesses; sexual habits; sexual development during puberty; and possibly inherited conditions.

Also standard during testing is the semen analysis wherein you'll submit semen at the doctor's office, which is sent to a laboratory to measure the number of sperm present, look for abnormalities in the morphology and motility, and signs of infections.60 Since sperm counts fluctuate from one specimen to the next, several semen analysis tests are done over a period of time to ensure accurate results.36 If your sperm analysis is normal, your doctor will likely recommend thorough testing of your female partner before conducting any more male infertility tests.61

If deemed appropriate, your doctor may recommend additional tests to help identify the cause of your infertility which may include: testicular biopsy;62 anti-sperm antibody tests;63 specialized sperm function tests;36 scrotal or transrectal ultrasounds;64 hormone testing;65 post-ejaculation urinalysis;36 and/or genetic tests.66

The Clinical Rational For Treating Male Infertility

Fertility is improved by either correcting an underlying problem, though sometimes an exact cause of infertility can't be identified, or by trying treatments that may be helpful which may include:67686970

  • Varicocele surgery to correct an obstructed vas deferens.
  • Antibiotic treatments that may cure an infection of the reproductive tract.
  • Assisted reproductive technology (ART) treatments involve obtaining sperm through normal ejaculation, surgical extraction or from donor individuals, then inserted into the female genital tract, or using sperm to perform in vitro fertilization or intracytoplasmic sperm injection.
  • Hormone treatments and medications
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