Where conception really begins: hormones.
Most of us are familiar with many of the words -- testosterone, progesterone, estrogen -- but some may be very new. While a lot of folks can certainly become pregnant without ever knowing a thing about the hormonal relay system in their body, if you're really into conceiving, this information is the foundation of everything else you'll learn.
Interestingly, the hormones which control reproduction are the same chemicals for both women and men. Here, we'll list them all, and discuss the role of each as they pertain to a woman's fertility. Follow along...
Secreted by the hypothalamus, part of your brain, into the pituitary gland. As an interesting aside, the hypothalamus also secretes substances such as endorphins, which can control our moods to some extent. It also acts as the body's thermostat, assuring that our body becomes neither too hot nor too cold to function.
Secreted by the pituitary gland, located behind your nose, after receiving the GnRH signal from the hypothalamus. FSH is responsible for taking immature follicles (sort of, ovulation wannabe's) to a more mature state.
As the FSH generated into the bloodstream by the pituitary (in your head) is causing immature follicles (in your ovaries) to mature, the growing follicles are secreting estrogen. Estrogen is crucial to the development of a healthy endometrial lining (in preparation to support a pregnancy).
(There are actually two forms of estrogen (estradiol and estrone), with estradiol being the form that is important to conception. Most people are more familiar with the generic term "estrogen.")
Once your pituitary gland senses the growing amount of estrogen in the bloodstream, it cuts back on producing FSH and releases a surge of LH.
LH runs back down to your ovaries and tells the follicles to start making use of the progesterone that is being secreted by the ovary. Progesterone is used by a woman's body to sustain pregnancy from fertilization through delivery.
This completes what is known as your ovulatory cycle's follicular phase.
About 36 hours after the LH surge, ovulation occurs when the chosen egg is released from its follicle. The follicle now becomes the corpus luteum, which begins producing more progesterone in an attempt to prepare the female body for pregnancy.
If conception does not occur, progesterone levels fall naturally, which signal the hypothalamus again to pulsate GnRH.
© Tracy Morris