Ovarian Cysts Causes

Xenoestrogens are Suspected of Causing Ovarian Cysts

Ovarian Cysts are products of failed or disordered ovulation. A functional ovarian cyst is formed when the follicle does NOT release its egg, and the follicle continues to grow forming a cyst.  An ovarian cyst can also be formed even if the follicle releases the egg, the hole where the egg is released closes up, the corpus luteum is NOT formed, and the cyst continues to grow.

It is now believed that xenoestrogens may contribute to ovarian cysts.

Normal Cycle

Let us review how a normal menstrual cycle occurs.  The hypothalamus is a portion of the brain in the lower portion of the brain.  The pituitary gland is even lower and underneath the brain.  

1. Low levels of estrogen and progesterone stimulate the hypothalamus to send slow pulses of gonadatropin-releasing hormone (GnRH) to the pituitary gland.

2. Stimulated by slow pulses of GnRH, the pituitary sends follicle-stimulating hormone (FSH) to the ovary, which initiates the maturation of ova in follicles.  The follicles then produce estrogen. 

3. In about 10 days, the high estrogen level signals the hypothalamus to produce fast pulses GnRH.  These fast pulses of GnRH tell the pituitary gland to produce luteinizing hormone (LH).  Luteinizing hormone (LH) promotes ovulation.  The follicle after ovulating turns into the corpus luteum.  The corpus luteum produces progesterone. After midcycle, the luteal phase GnRH pulse rate slows dramatically, to levels below that of the follicular phase.

4. The maturing ovarian follicles produce estrogen, which promotes proliferation of ovarian cells.  After ovulation, the follicle becomes the corpus luteum (yellow body) and produces progesterone, which becomes the dominant gonadal hormone during the second half of the cycle and converts the proliferative endometrium (lining of the uterus) into secretory endometrium.

5. If pregnancy does NOT occur, the corpus luteum involutes (atrophies) and the production of both estrogen and progesterone falls, a signal for menstruation, and the shedding of the endometrium.

6. Serum levels of estrogen and progesterone fall as they are metabolized and excreted.

7. The fall of estrogen and progesterone stimulates slow pulses of GnRH, starting the cycle anew.

Disordered Ovulation and an Ovarian Cyst is Formed

Your ovaries normally grow cyst like structures called follicles each month. Follicles are little "chemical factories" that produce the hormones estrogen and progesterone and release an egg when you ovulate.

Sometimes a normal monthly follicle just keeps growing. When that happens, it becomes known as a functional cyst. This means it started during the normal function of your menstrual cycle. There are two types of functional cysts:

• Follicular ovarian cyst. Ovulation initiates a complex chain reaction. The follicle holding your egg takes its cue from your brain's pituitary gland via a hormone called luteinizing hormone (LH), which is necessary for conception. When everything goes according to plan, your egg is released and begins its journey down the fallopian tube in search of fertilization. A follicular cyst begins when LH doesn't surge and the chain reaction doesn't start. The result is a follicle that doesn't rupture or release its egg. Instead, it grows and grows until it becomes a cyst. Follicular cysts are usually harmless, rarely cause pain and often disappear on their own within two or three menstrual cycles.
• Corpus luteum ovarian cyst. If LH does surge and your egg is released, another chain of events starts. The follicle then responds to LH by producing large quantities of estrogen and progesterone in preparation for conception. This change in the follicle is called the corpus luteum. However, sometimes after the egg's release, its escape hole seals off and tissues accumulate inside, causing the corpus luteum to expand into a cyst. Although this cyst usually disappears on its own in a few weeks, it can grow to almost 4 inches in diameter and has the potential to bleed into itself or twist the ovary, causing pelvic or abdominal pain. If it fills with blood, the cyst may rupture, causing internal bleeding and sudden, sharp pain.