Until I was 21 I didn’t really know what my body was doing during my cycle. I got my period and moved on. I had heard that women ovulated 2 weeks after their period starting, but that was it. In the summer after my oldest was born I had had it with my Mirena IUD. I had been having cramps that ranged from mild, to putting me on the floor. It also effected my mood in a negative way. So I decided on a hormone free birth control. I was skeptical about the copper IUD. After my experience with my Mirena, I did not really want something that sat in my uterus.
I stumbled upon natural family planning. I read a lot of material online. My friend Melissa was very helpful when I was first figuring it out, by providing me materials to read, answering questions, and has answered questions I have randomly asked since.
I use the sympto-thermal method of Natural Family Planning. It uses cervical fluid, and your basal body temperature (your temperature right upon waking) to determine fertility. How does it determine fertility? Science. Women’s bodies are so cool. When a woman ovulates her temperature rises.When you collect this data, you can get some really useful information from it.
So why does a woman’s temperature change when she ovulates? Hormones. There are 4 different hormones involved in a woman’s menstrual cycle. The first is the Follicle Stimulating Hormone, which is released by the pituitary gland. (Which is in the brain.) Girls are born with the number of eggs in their ovaries they will have for their lifetime.
The eggs are housed in a follicle. When FSH is released during a woman’s cycle it causes about 15 eggs in each ovary to mature. The follicles of these maturing eggs begin to produce estrogen. When a woman’s body reaches an estrogen threshold, the pituitary gland produces the third hormone, Luteinizing Hormone. The surge of this hormone causes whichever of the maturing eggs that has become the largest to be released from the ovary. At this point, the follicle that housed that egg caves in on itself and becomes a corpus luteum.
This image was taken from Encyclopedia Britanica for more information about the Corpus Luteum visit their site here.
This then produces the fourth hormone progesterone. It is this hormone that is responsible for the temperature shift. One cannot tell whether or not you are fertile from your temperature. One cannot get any information from just a single temperature reading. It is a pattern in which one can tell if ovulation occurred. This separates a woman's cycle into two parts. The Follicular Phase before ovulation, and the Luteal Phase after ovulation.
This is where other signs of fertility come into play. The main one is cervical fluid. Unlike men, women are not fertile all the time, just the days around ovulation. During this time a woman’s body will produce a fluid so that sperm can easily reach the egg. Throughout the month cervical fluid will change from dry, sticky, creamy, wet/slippery/egg-white. It is his sign accompanied by the thermal shift that indicates that ovulation occurred. Another sign of fertility in cervical position. A woman’s cervix changes position throughout your cycle that a woman could feel with her fingers.. There are other secondary signs as well. Some women feel cramping, others breast tenderness. Some feel an increased sexual desire around the time they ovulate.
So, now that we know what is happening, why is knowing this cool? Check out Part Two!