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New life begins when an egg from a woman is fertilised by sperm from a man. Eggs (ova) are made in the ovaries, and sperm in the testicles. The ovaries and testicles (gonads) also make sex hormones. The female reproductive systemThe female reproductive organs are the vagina, womb (uterus), fallopian tubes and ovaries:
The menstrual cycleHormones secreted by the ovaries and a small gland in the brain called the pituitary gland control the menstrual cycle. The average menstrual cycle is around 28 days. After a period, rising levels of the hormone oestrogen help to thicken the lining of the womb (the endometrium). At mid-cycle, an egg is released from one of the ovaries (ovulation). If the egg is fertilised on its journey down the fallopian tube, it lodges in the womb lining. If the egg is unfertilised, falling levels of the hormone progesterone make the womb lining come away. This is called a period, or menstruation. The cycle then repeats. When you want to have a baby you can improve your chance of getting pregnant if you know about ovulation and the ‘fertile window’ in the menstrual cycle. Read more on ovulation and the fertility . The egg (ovum)A woman’s entire egg supply is developed when she is still an unborn baby. At the start of puberty, the eggs are ripened inside the ovary and one is released every month. Each egg contains genetic material. At menopause, the ovaries stop making hormones and eggs are no longer ripened or released. Female reproductive system problemsSome reproductive health conditions women may experience include: The male reproductive systemThe male reproductive organs are the penis, the testicles, the epididymis, the vas deferens and the prostate gland:
Male reproductive hormonesHormones are chemical messengers made by glands in the body. Androgens are the hormones that make men ‘male’. Androgens are responsible for sexual functioning, fertility and secondary sexual characteristics such as muscle mass, height, deep voice and body hair (including the beard). The most important androgen is testosterone, which is manufactured in the testicles. The spermThe sperm is the male reproductive cell. Its role is to fertilise an egg. It contains the man’s genetic material. A sperm is tadpole-shaped and around 60 microns in length (one micron is a millionth of a metre). It has a lashing tail, which helps it to ‘swim’ towards a waiting egg. Sperm production continues throughout a man’s life, from puberty into old age but the quality of a man’s sperm declines from about age 45. Male reproductive system problemsSome of the reproductive health conditions men may experience include: Where to get help
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Content on this website is provided for information purposes only. Information about a therapy, service, product or treatment does not in any way endorse or support such therapy, service, product or treatment and is not intended to replace advice from your doctor or other registered health professional. The information and materials contained on this website are not intended to constitute a comprehensive guide concerning all aspects of the therapy, product or treatment described on the website. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions and to ascertain whether the particular therapy, service, product or treatment described on the website is suitable in their circumstances. The State of Victoria and the Department of Health shall not bear any liability for reliance by any user on the materials contained on this website. Overview Each month during the years between puberty and menopause, a woman’s body goes through a number of changes to get it ready for a possible pregnancy. This series of hormone-driven events is called the menstrual cycle. During each menstrual cycle, an egg develops and is released from the ovaries. The lining of the uterus builds up. If a pregnancy doesn’t happen, the uterine lining sheds during a menstrual period. Then the cycle starts again. A woman’s menstrual cycle is divided into four phases:
The length of each phase can differ from woman to woman, and it can change over time. The menstrual phase is the first stage of the menstrual cycle. It’s also when you get your period. This phase starts when an egg from the previous cycle isn’t fertilized. Because pregnancy hasn’t taken place, levels of the hormones estrogen and progesterone drop. The thickened lining of your uterus, which would support a pregnancy, is no longer needed, so it sheds through your vagina. During your period, you release a combination of blood, mucus, and tissue from your uterus. You may have period symptoms like these:
On average, women are in the menstrual phase of their cycle for 3 to 7 days. Some women have longer periods than others. The follicular phase starts on the first day of your period (so there is some overlap with the menstrual phase) and ends when you ovulate. It starts when the hypothalamus sends a signal to your pituitary gland to release follicle-stimulating hormone (FSH). This hormone stimulates your ovaries to produce around 5 to 20 small sacs called follicles. Each follicle contains an immature egg. Only the healthiest egg will eventually mature. (On rare occasions, a woman may have two eggs mature.) The rest of the follicles will be reabsorbed into your body. The maturing follicle sets off a surge in estrogen that thickens the lining of your uterus. This creates a nutrient-rich environment for an embryo to grow. The average follicular phase lasts for about 16 days. It can range from 11 to 27 days, depending on your cycle. Rising estrogen levels during the follicular phase trigger your pituitary gland to release luteinizing hormone (LH). This is what starts the process of ovulation. Ovulation is when your ovary releases a mature egg. The egg travels down the fallopian tube toward the uterus to be fertilized by sperm. The ovulation phase is the only time during your menstrual cycle when you can get pregnant. You can tell that you’re ovulating by symptoms like these: Ovulation happens at around day 14 if you have a 28-day cycle — right in the middle of your menstrual cycle. It lasts about 24 hours. After a day, the egg will die or dissolve if it isn’t fertilized. Did you know? After the follicle releases its egg, it changes into the corpus luteum. This structure releases hormones, mainly progesterone and some estrogen. The rise in hormones keeps your uterine lining thick and ready for a fertilized egg to implant. If you do get pregnant, your body will produce human chorionic gonadotropin (hCG). This is the hormone pregnancy tests detect. It helps maintain the corpus luteum and keeps the uterine lining thick. If you don’t get pregnant, the corpus luteum will shrink away and be resorbed. This leads to decreased levels of estrogen and progesterone, which causes the onset of your period. The uterine lining will shed during your period. During this phase, if you don’t get pregnant, you may experience symptoms of premenstrual syndrome (PMS). These include:
The luteal phase lasts for 11 to 17 days. The average length is 14 days. Every woman’s menstrual cycle is different. Some women get their period at the same time each month. Others are more irregular. Some women bleed more heavily or for a longer number of days than others. Your menstrual cycle can also change during certain times of your life. For example, it can get more irregular as you get close to menopause. One way to find out if you’re having any issues with your menstrual cycle is to track your periods. Write down when they start and end. Also record any changes to the amount or number of days you bleed, and whether you have spotting between periods. Any of these things can alter your menstrual cycle:
Here are a few signs of a problem with your menstrual cycle:
If you have these or other problems with your menstrual cycle or periods, talk to your healthcare provider. Every woman’s menstrual cycle is different. What’s normal for you might not be normal for someone else. It’s important to get familiar with your cycle — including when you get your periods and how long they last. Be alert for any changes, and report them to your healthcare provider. |