Understanding Infertility Causes
Traditionally, infertility is defined as the inability to conceive, despite one year of unprotected intercourse. At the Los Angeles Reproductive Center (LARC), we recognize that the traditional definition of infertility does not reflect all of those individuals and couples who may benefit from fertility treatment. For so many people, one year of “trying to conceive” doesn’t make any sense. For others, a year of trying may actually diminish their chance of conception. Those with irregular periods, age greater than 35, low sperm count, single individuals, same sex couples, endometriosis, those seeking fertility preservation and many more, can benefit from our expertise without waiting for a certain amount of time to pass.
To understand the factors that can contribute to infertility, one must first understand the normal process of conception.
The process of natural conception actually begins when a female embryo is approximately five weeks gestation. At that time, the embryo begins producing cells that will eventually become eggs (oocytes). For the next 15 weeks, egg production is a top priority for the embryo, and the process continues in earnest. By 20 weeks gestation, the embryo has produced a lifetime supply of eggs, approximately 6 million. At this point, egg production permanently stops.
Those eggs are stored in the ovaries for the next 9-13 years, until that embryo becomes a pubescent girl. By this time, significant portions of the eggs have already absorbed back into the ovaries. Most girls have approximately 500,000 eggs remaining in their ovaries at the time of their first menstrual cycle.
At the beginning of each menstrual cycle, the brain sends a signal down to the ovaries instructing them to select a group of eggs, which will potentially be available for ovulation that month. The size of this group is very important and is known as the ovarian reserve. The larger the ovarian reserve, the greater chance that any of the eggs will be able to become a baby. When we are younger, the reserve is greatest. As we age, the reserve decreases. This diminishment of ovarian reserve is the basis for the age-related natural decline in fertility.
Once the group of eggs is selected, the brain and ovary communicate over the next two weeks, until one egg has been designated for ovulation. Next, the brain sends a final signal to the ovary, instructing it to release the designated egg; this is called ovulation.
Once released, the egg must be “picked up” by the finger like extensions protruding from the end of the fallopian tubes. These projections are called fimbria. The fimbria usher the egg into the lumen of the fallopian tube where, if intercourse was properly timed, it will meet sperm. If egg and sperm meet within the appropriate segment of fallopian tube, fertilization can occur.
Once fertilized, the embryo travels through the fallopian tube for the next five to six days until it enters the body of the uterus.
In the uterus, the embryo makes contact with the specialized tissue lining the cavity, the endometrium, where it implants and grows for the next nine months Next thing you know…out comes the baby
Drs. Nurit Winkler and Marc Kalan of Los Angeles Reproductive Center are a unique fertility clinic focused on treating patients like family and built upon the principles of communication, compassion, warmth, openness, and service that accompanies an exceptional pregnancy rate. Contact us today to schedule an appointment.