Infertility is a sensitive and challenging concern for the nearly one in six couples who have trouble conceiving a child. 40-50% of cases are caused by female factors and 40-50% are attributed to male factors, so infertility affects both sexes equally. The remaining cases fall into the unexplained infertility category. Please keep in mind that even if the cause cannot be diagnosed, treatments can still be successful. There are effective courses of treatment for most causes of infertility.
If you are experience trouble conceiving, there are a few things you should know:
- You are not alone. Fertility issues are more common than you may think.
- Treatments are available. In recent years we have seen tremendous advances in reproductive diagnostic procedures and treatments.
- The chance of conception decreases as you age. If you are in your late 20s or older and have not been successful in conceiving a child, we encourage you to seek help. The sooner your infertility is diagnosed and treated, the better chance you will be able to conceive a child.
Female Fertility Overview
Women are born with all the eggs they will ever have. When a woman reaches puberty, the number of eggs is about 450,000. At this point, your body begins to generate hormones that will cause the eggs to mature and be released. The average menstrual cycle is 28 days. At the beginning of each cycle a group of follicles (most containing an egg) begins to grow and develop with the help of Follicle Stimulating Hormone (FSH). Only one of the many follicles reaches a dominant stage. The others undergo the natural process of atresia (they die off).
During the second week of your cycle, the follicles produce estrogen, this stimulates the brain to release Luteinizing Hormone (LH). Estrogen helps thicken the uterine lining (endometrium). It also stimulates the cervix to produce a thin, slippery mucus through which sperm can swim. Ovulation occurs when the LH surge causes the dominant follicle to release the egg. At this stage of the process, the follicle is known as the corpus luteum. The corpus luteum creates yet another hormone, progesterone, which prepares the uterus to receive the fertilized egg.
If the egg does not get fertilized by a sperm, or if a fertilized egg does not implant, then the corpus luteum shrinks, the progesterone level declines and the uterus will begin to shed as menstruation starts and the cycle starts over.
Causes of Infertility
The most common causes of reduced fertility in women include:
Fertility declines as women age. Commonly, this decline begins slowly in the late 20’s and drops off more steeply by age 37. It is very rare for women in their late 40’s and older to conceive a child naturally because aging eggs do not fertilize, implant or respond to stimulation medications as well as younger eggs. Older eggs also present an increased risk of pregnancy loss and babies with chromosomal abnormalities.
Amenorrhea means the absence of periods. There are two types: primary and secondary. Primary is often diagnosed when a woman does not have any menstrual periods before she is 16 years old. Secondary can occur when a woman has previously menstruated, but then stops menstruating for 3-6 months or more.
Endometriosis is a common disorder that occurs when endometrial tissue, which lines the uterus, grows outside the uterine cavity. This misplaced tissue may implant and grow anywhere in the body, most commonly within the abdominal cavity.
Endometriosis affects everyone differently. Some women experience no symptoms; others have severe menstrual cramps, abnormal uterine bleeding, painful intercourse and other symptoms. Women with very little endometriosis may endure severe pain, while those with extensive endometriosis may not feel a thing.
Endometriosis can hinder conception by producing scar tissue or adhesions which bind the ovaries, fallopian tubes and intestines together. These adhesions can interfere with the release of eggs from the ovaries or the pick-up of eggs by the fallopian tube, thereby reducing the chance of pregnancy.
Your physician may suspect endometriosis based on your history and pelvic exam, but additional tests are necessary to confirm a diagnosis. The only valid diagnostic tool is often a laparoscopy. Ultrasound and blood tests may also be used to confirm a diagnosis.
A series of complex steps must occur to produce a fertilizable egg each month. If one thing goes awry, you won’t be able to get pregnant. A number of conditions can interfere with, or prevent, ovulation including:
- Polycystic Ovarian Syndrome
- Thyroid disease
- Hyperprolactinemia, a hormone that stimulates milk production and suppresses ovulation
- Low levels of fertility hormones (FSH and LH)
- Premature Ovarian Failure
- Extreme weight loss or weight gain
- Excessive exercise
- Eating disorders
A decline in both egg quantity and quality make it challenging for a woman to conceive. Some women experience ovarian dysfunction well before menopause. Known as Premature Ovarian Failure (POF), or early menopause, it occurs when a woman under the age of 40 stops producing eggs capable of fertilization. On average, the age for natural menopause is about 51, but women with POF go into menopause much sooner.
Ovulatory disorders are the most common cause of female infertility. The good news is that many of these issues are treatable.
Polycystic Ovary Syndrome
Polycystic ovary syndrome (PCOS), or polycystic ovary disease (PCOD), is an endocrine disorder. It is one of the most common hormone problems women of reproductive age face. Despite the name, ovarian cysts are not usually present, although some women have many small follicles visible on ultrasound. Egg production is affected by the hormone imbalance. Some women with PCOS experience irregular ovulation, often having less than eight menstrual cycles per year. Other women with PCOS can have more than one period of bleeding per month and each episode can be lengthy.
PCOS is sometimes associated with a resistance to insulin. Elevated insulin levels stimulate the ovaries to produce androgens (male hormone). Women with PCOS are also at increased risk for diabetes, heart disease and high cholesterol. Proper diet and exercise are very important in managing this condition.
Recurrent Pregnancy Loss
When a pregnancy is lost prior to 20 weeks gestation it’s called a miscarriage. It occurs in 15-20% of pregnancies and the risk increases with age. Most miscarriages, also known as spontaneous abortions or pregnancy losses, occur within the first trimester. If a viable fetus (heart activity is seen by ultrasound) is detected in the first 12 weeks of gestation, there is a less than 5% chance pregnancy loss will occur. If vaginal bleeding occurs after a viable fetus is detected, the chance of miscarriage rises to approximately 20%.
The chances of experiencing recurrent pregnancy loss vary widely. Women who have had at least one full-term normal delivery have a better chance of a subsequent healthy pregnancy, despite having a miscarriage. Extensive evaluation usually only occurs after two-three consecutive miscarriages. Half the couples who have recurrent pregnancy loss will find out the cause, and can be treated. An abnormal chromosome pattern in the embryo is the cause of most miscarriages. The cause is almost always unrelated to the health of the mother, although the risk of miscarriage increases for women 35 years of age and older. By age 40, the risk is 35-40% and by 45 years of age it is more than 50%.
Recurrent pregnancy loss may be due to some of the following factors:
- Abnormalities in the shape of the uterus
- Uterine fibroids
- Genetic abnormalities
- Hormonal disorders
- Immunological factors
Unexplained infertility is defined as more than three years of infertility with normal semen analysis, normal ovulation by basal body temperature charting or serum progesterone and normal tubes and pelvic cavity on laparoscopy, with or without a hysterosalpingogram (HSG). Patients with normal studies and less than three years infertility have a 60% chance of conceiving within 18 months without therapy. After three years, however, the chances are 30%, or lower, of ever conceiving depending on the woman’s age and the length of infertility. This number breaks down to approximately 3%, or less, per month .
With unexplained infertility, or when traditional treatments have failed, advanced infertility treatments may be recommended. These include HS/IUI and IVF/ICSI.
Tubal Factor Infertility
The fallopian tubes are an important piece of successful fertilization and pregnancy. As many as 25% of infertile women find that damaged tubes are the cause. Modern techniques, however, have enabled many women with tubal damage to have healthy pregnancies.