Normal Menstrual Cycle - Normal Menstrual Cycle
The menstrual cycle is the
series of changes your body goes through to prepare for a possible pregnancy.
About once a month, the
uterus grows a new, thickened lining (endometrium)
that can hold a
fertilized egg
. When there is no fertilized egg to
start a pregnancy, the uterus then sheds its lining. This is the monthly
menstrual bleeding
(also called menstruation or menstrual period) that you have
from your early teen years until your menstrual periods end around age 50
(menopause).
See a picture of a
woman's reproductive system
.
The menstrual cycle is measured from the first day of menstrual bleeding, Day 1, up to Day 1 of your next menstrual bleeding. Although 28 days is often cited as the "regular" cycle length, only 15% of women actually have such a cycle.5
- A teen's cycles tend to be long (up to 45 days), growing shorter over several years.2
- Between ages 25 and 35, most women's cycles are regular, generally lasting 21 to 35 days.1
- Around ages 40 to 42, cycles tend to be the shortest and most regular. This is followed by 8 to 10 years of longer, less predictable cycles until menopause.5
Three phases of the menstrual cycle
The phases of your menstrual cycle are triggered by hormonal changes.
Menstrual period
On Day 1 of your cycle, the thickened lining (endometrium) of the uterus begins to shed. You know this as menstrual bleeding from the vagina. A normal menstrual period can last 4 to 6 days.5
Most of your menstrual blood loss happens during the first 3 days. This is also when you might have cramping pain in your pelvis, legs, and back. Cramps can range from mild to severe. The cramping is your uterus contracting, helping the endometrium shed. In general, any premenstrual symptoms that you've felt before your period will go away during these first days of your cycle.
Follicular phase
During the follicular phase, an egg follicle on an ovary gets ready to release an egg. Usually, one egg is released per cycle. This process can be short or long and plays the biggest role in how long your cycle is. At the same time, the uterus starts growing a new endometrium to prepare for pregnancy.
The last 5 days of the follicular phase, plus ovulation day, are your fertile window. This is when you are most likely to become pregnant if you have sex without using birth control.
Luteal (premenstrual) phase
This phase starts on ovulation day, the day the egg is released from the egg follicle on the ovary. It can happen any time from Day 7 to Day 22 of a normal menstrual cycle. During ovulation, some women have less than a day of red spotting or lower pelvic pain or discomfort (mittelschmerz). These signs of ovulation are normal.
- If the egg is fertilized by sperm and then implants in (attaches to) the endometrium, a pregnancy begins. (This pregnancy is dated from Day 1 of this menstrual cycle.)
- If the egg is not fertilized or does not implant, the endometrium begins to break down.
WebMD Medical Reference from Healthwise
Normal Menstrual Cycle Topics
ENABLEX is a prescription medicine used in adults to treat the following symptoms due to a condition called overactive bladder:
- · having a strong need to go to the bathroom right away (also called "urgency")
- · leaks or wetting accidents (also called "urinary incontinence")
- · having to go to the bathroom too often (also called "urinary frequency")
IMPORTANT SAFETY INFORMATION
You should not take once-daily ENABLEX if you have certain types of stomach problems, glaucoma, or have trouble emptying your bladder. Side effects of ENBLEX include blurred vision, and more commonly dry mouth, constipation, indigestion, and abdominal pain. Use caution when doing certain activities until you know how ENBALEX affects you.
VIVELLE-DOT (estradiol transdermal system) IS AVAILABLE BY PRESCRPTION ONLY.
INDICATION
Vivelle-Dot is used after menopause to: reduce moderate to severe hot flashes; treat moderate to severe dryness, itching and burning in or around the vagina; help reduce your chances of getting osteoporosis (thin weak bones); and treat certain conditions in which a young woman's ovaries do not produce enough estrogens naturally. Vivelle-Dot 0.025 mg/day is only used to prevent osteoporosis from menopause. If you use Vivelle-Dot only to treat your dryness, itching, and burning in and around your vagina or if you use Vivelle-Dot only to prevent osteoporosis from menopause, talk with your healthcare professional about whether a different treatment or medicine without estrogens might be better for you.
IMPORTANT SAFETY INFORMATION
Estrogens increase the chances of getting cancer of the uterus (womb). Report any unusual vaginal bleeding right away while you are taking estrogens. Vaginal bleeding after menopause may be a warning sign of cancer of the uterus (womb).
Do not use estrogens with or without progestins to prevent heart disease, heart attacks, or strokes. Using estrogens with or without progestins may increase your chances of getting heart attacks, strokes, breast cancer, and blood clots. Using estrogens with progestins may increase your risk of dementia (decline in memory and thinking skills).
Vivelle-Dot should not be used if you have unusual vaginal bleeding; currently have or have had certain cancers, including cancer of the breast or uterus; had a stroke or heart attack in the recent past (for example, in the past year); currently have or have had blood clots; currently have or have had liver problems; or think you may be, or know that you are, pregnant.
The most common side effects that may occur with Vivelle-Dot are headache, breast tenderness, and back pain.
You and your healthcare professional should talk regularly about whether you still need treatment with Vivelle-Dot.
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.
Please see Full Prescribing Information for Vivelle-Dot.


