What you need to know
There are many factors involved in achieving a successful pregnancy. These factors include:
- The production of healthy sperm by the man and healthy eggs by the woman
- Unblocked fallopian tubes that allow the sperm to reach the egg
- The sperm's ability to fertilise the egg when they meet
- A genetically healthy embryo
- The ability of the embryo to implant in the uterus.
Repeatedly encountering difficulty at any of these steps can lead to infertility.
Ovulation and the Menstrual Cycle
Every month, your body goes through normal and natural changes that assist your ovaries in releasing an egg, which may or may not get fertilised during the month. This process is known as the menstrual cycle. Day one of your cycle is the first day of menstruation; this is the first day that you bleed during your period. The length of your cycle can vary every month. To determine your cycle's length, simply count the days from the first day of your period up to, but not including, the first day of your next period. The average woman's menstrual cycle lasts about 28 days but it is perfectly normal for your cycle to last anywhere from 24 to 34 days.
The typical menstrual cycle begins with your period during which time your low hormone levels signal to your body to begin producing more hormones. Although your egg follicles will begin to develop as many as 20 eggs, only one will mature and be released into your fallopian tube about halfway through your menstrual cycle. The process of your egg follicles releasing the egg is known as ovulation. On average, ovulation occurs 14 days before the start your period. However, it is normal for a woman to ovulate anywhere from 12 to 18 days before menstruation.
This increase in hormones not only helps to develop an egg but also your endometrium (the lining of the uterus), which becomes thicker and more suitable for implantation of a fertilised egg. Your cervical mucus also changes as your cycle progresses, going from dry and thick at the start of your cycle to thin and slippery around the time of ovulation. This thinner cervical mucus will make it easier for sperm to swim towards the fallopian tubes and the released egg.
Once an egg has been released, the sides of the fallopian tube periodically spasm aiding the egg in travelling down the tube towards the uterus. If the egg fails to be fertilised during this time, it will break up once it reaches the uterus. Additionally, since your thickened endometrium is also no longer needed as there is no fertilised egg to implant itself into the lining, the lining will shed over a period of three to eight days. This discharge is what makes up your menstrual flow.
The female reproductive organs
The female reproductive organs are comprised of a vagina, a cervix, a uterus, fallopian tubes and ovaries. All of these organs work together to help a woman menstruate, conceive and carry a baby to term.
Vagina: This tube like structure connects your internal reproductive organs with your external genitalia.
Cervix: This part of your reproductive organs is situated between the vagina and uterus. It secretes mucus that can help or obstruct sperm from fertilising an egg.
Uterus: Also known as the womb, the uterus is a muscular organ made up of three layers: the peritoneum (outer layer), myometrium (middle layer) and endometrium (inner lining). An egg that has been fertilised will implant itself into the endometrium lining and will continue to develop in the uterus throughout the pregnancy.
Fallopian Tubes: The fallopian tubes extend off the upper sides of the uterus and lead up to the ovaries. They have 20 to 25 finger-like structures on their ends that hover just above the ovaries and work to collect the mature egg when it is released. It is in the fallopian tubes that fertilisation of the egg will take place.
Ovaries: Ovaries are the storing house for your egg follicles; every month, one of these egg follicles will mature and release an egg into the fallopian tubes. The ovaries are also responsible for producing estrogen and progesterone, which are vital for proper reproductive function. The eggs in each ovary are made before a woman is born. The most eggs a woman will ever have - about 7 million - is when there's still 20 weeks to go before birth. From this time on, the number of eggs will diminish in number, and none will be replaced. A girl is born with about 2 million eggs. At the time she has her first period there are about 400,000.
The Male Reproductive Organs
The testes lie in the scrotum, the pouch of skin located beneath the man's penis. The testes are the organs that produce sperm and testosterone.
From the testes, sperm pass slowly through the coiled channels of the epididymis, where they mature.
Once sperm are mature, they move into the vas deferens, a tube that connects the epididymis with the urethra via a common ejaculatory duct. The entire process of sperm formation takes approximately 72 days.
Once an egg has been released from the ovaries, it will begin to travel down the fallopian tubes towards the uterus. As it advances towards the uterus, it begins to produce an enzyme that helps to attract and guide any sperm that may have been ejaculated into the female reproductive system during sex.
Although a man releases millions of sperm when he ejaculates during orgasm, only a few hundred will be able to make it all the way from the cervix up into the uterus and then into the correct fallopian tube. Just one sperm will then be able to make its way through the eggs tough coating to fertilise the egg. The fertilised egg will then continue travelling down the fallopian tube to the uterus. Once in the uterus, the egg will implant itself into the endometrial lining and officially become an embryo.