Infertility Related to the Female’s Eggs
Conditions That Can Result in Tubal Damage
Dr. Michele Evans Explains Endometriosis
Additional Causes of Tubal Damage
- Previous surgical manipulation of the uterine cavity such as D&C, fibroid or polyp surgery or to remove retained placentas after a delivery.
Ovulation Disease and Disorders
Background: The ovulatory cycle in women starts with follicular recruitment. The ovary, which is endowed with a set complement of eggs well before birth, is the organ responsible for ovulation. Inside the ovaries, hundreds of small “preantral follicles” exists, that upon adequate signals from a small gland in the brain called “the pituitary gland”, will start growing just before the initiation of menstruation. Of all the follicles that start growing, only one usually will reach maturity and ovulate. The rest will die-off in the process.
A hormone called Follicle Stimulating Hormone or FSH is secreted into the blood by the pituitary gland. Its role is to reach the ovaries and order a complement of preantral follicles to start growing. Another hormone called, Luteinizing Hormone or LH, will also assist in this process. As these follicles grow, one of them becomes Dominant. It starts secreting certain chemicals that will cause the others to die-off or stop from growing. Roughly 13-14 days after the start of the menstrual cycle, this dominant follicle will be ready to release its egg. This constitutes ovulation. Under the influence of a surge of the LH hormone by the pituitary gland, the dominant follicle will rupture and release the egg to the surface of the ovary where it will hopefully be picked-up by the fallopian tube and be transported to the tubal lumen where it will await for the sperm.
The egg, which is present inside the follicle also matures as the follicle is growing. As the egg and follicle mature, the granulose cells, which line the cavity of the follicle, start secreting a hormone called Estrogen, which can be measured with a simple blood test. The level of this hormone can provide us with valuable information regarding the number of eggs growing and their maturation stage. A typical menstrual cycle can be divided into two halves: The first half, from the start of the menstrual bleed up to day 14, is called the follicular phase and is the time during which the dominant follicle reaches maturity and is released at mid-cycle or day 14.
Conditions Associated with Abnormal Ovulation
Another common cause of female infertility is the condition referred to Polycystic Ovarian Disease or Syndrome (PCO). Many such patients also have other signs of the disease such as excess hair growth, especially on the face, inner thighs and lower abdomen. Some also suffer from excess body weight. There are other conditions associated with abnormal ovulation and the specialist will perform certain hormonal testing to try and elucidate the possible cause.
PCOS is one of the most common causes of abnormal ovulation and infertility in women. The exact cause of the disease is not well known but recent studies have demonstrated a clear link between PCO and Insulin resistance. Hence the link between PCO and Diabetes. Women with PCO suffer from an abnormal Insulin metabolism which leads to higher levels of this hormone in blood to keep normal blood sugar levels. The higher Insulin level leads to increase male hormones which in turn lead to a disturbance of the whole ovulatory process and in some patients to hirsutism or excess body hair.
Poor Quality Eggs
It is also thought that some patients with PCO have poor quality eggs secondary to exposure to elevated male hormone levels and some suffer from an increased miscarriage rate. Some reports actually show a doubling of the rate. The Insulin is also the reason that PCO patients are at an increased risk of Diabetes later in life and should have periodic testing every 1-2 years to check for it.
Treatment of PCO involves ovulation induction. Initially the simpler oral medications are used such as Clomiphene citrate or Letrozole. In cases of failure, more aggressive treatment is used with injectable forms of ovulation inducing medications. For some, In Vitro Fertilization is needed as the ultimate therapy.