All About Menstruation

Elana Pearl Ben-Joseph, MD & Neil Izenberg, MD

Menstruation (a period) represents a major stage of puberty in girls; it's one of the many physical signs that a girl is turning into a woman. And like a lot of the other changes associated with puberty, menstruation can be confusing for women. Some women can't wait to start their periods, whereas others may feel afraid or anxious. Many women don't have a complete
understanding of a woman's reproductive system or what actually happens during the menstrual cycle, making the process seem even more mysterious.

Puberty and Periods
When girls begin to go through puberty (usually starting between the ages of 8 and 13), their bodies and minds change in many ways. The hormones in their bodies stimulate new physical development, such as growth and breast development. About 2 to 2 1/2 years after a girl's breasts begin to develop, she usually gets her first menstrual period.
About 6 months or so before getting her first period, a girl might notice an increased amount of clear vaginal discharge. This discharge is common. There's no need for a girl to worry about discharge unless it has a strong odor or causes itchiness.
The start of periods is known as menarche (pronounced: meh-nar-kee) . Menarche doesn't happen until all the parts of a girl's reproductive system have matured and are working together. Baby girls are born with ovaries, fallopian tubes, and a uterus. The two ovaries are oval-shaped and sit on either side of the uterus (womb) in the lowest part of the abdomen called the pelvis. They contain thousands of eggs, or ova. The two fallopian tubes are long and thin - like hollow strands of spaghetti (only a little bit thicker). Each fallopian tube stretches from an ovary to the uterus, a pear-shaped organ that sits in the middle of the pelvis. The muscles in a female's uterus are powerful and are able to expand to allow the uterus to accommodate a growing fetus and then help push the baby out during labor.
As a girl matures and enters puberty, the pituitary gland releases hormones that stimulate the ovaries to produce other hormones called estrogen and progesterone. These hormones have many effects on a girl's body, including physical maturation, growth, and emotions.
About once a month, a tiny egg leaves one of the ovaries - a process called ovulation - and travels down one of the fallopian tubes toward the uterus. In the days before ovulation, the hormone estrogen stimulates the uterus to build up its lining with extra blood and tissue, making the walls of the uterus thick and cushioned. This happens to prepare the uterus for
pregnancy: If the egg reaches the uterus and is fertilized by a sperm cell, it attaches to the cushiony wall of the uterus, where it slowly develops into a baby.
If the egg isn't fertilized, though - which is the case during most of a girl's monthly cycles - it doesn't attach to the wall of the uterus. When this happens, the uterus sheds the extra tissue lining. The blood, tissue, and unfertilized egg leave the uterus, going through the vagina on the way out of the body. This is a menstrual period. This cycle happens almost every month for several more decades (except, of course, when a female is pregnant) until a woman reaches menopause and no longer releases eggs from her ovaries. A menstrual cycle is counted from the first day of bleeding in one month to the first day of bleeding in the next month.

How Often Does a Woman Get Her Period?
Just as some girls begin puberty earlier or later than others, the same applies to periods. Some girls may start menstruating as early as age 9 or 10, but others may not get their first period until later in their teens. The amount of time between a woman's periods is called her menstrual cycle (the cycle is counted from the start of one period to the start of the next). Some women will find that their menstrual cycle lasts 28 days, whereas others might have a 24-day cycle, a 30-day cycle, or even a 35-day cycle.
Irregular periods are common in girls who are just beginning to menstruate. It may take the body a while to sort out all the changes going on, so a girl may have a 28-day cycle for 2 months, then miss a month or have two periods with hardly any time in between them, for example. Usually, after a number of months, the menstrual cycle will become more regular. Many women continue to have irregular periods into adulthood, though. As a girl gets older and her periods settle down - or she gets more used to her own unique cycle - she will probably find that she can predict when her period will come.

How Long and How Much?
The amount of time that a woman has her period also can vary. Some women have periods that last just 2 or 3 days; other women may have periods that last 7 days or longer. The menstrual flow - meaning how much blood comes out of the vagina - can vary widely from person to person, too. Some women have such light blood flow that they wonder if they even have their period at all.
Other women may be concerned that they're losing too much blood. It can be a shock to see all that blood, but it's highly unlikely that a woman will lose too much: For most women an entire period consists of anywhere from a few spoonfuls to less than 1/2 cup (118 milliliters) of blood - it just looks like a lot! It is possible for a woman to lose an excessive amount of blood during her period, but it's not at all common. (In some cases, a woman can bleed too much because she has a medical condition - such as von Willebrand disease.) The amount of blood a woman loses and how long her period lasts can differ from month to month.
If you're worried about your blood flow or whether your period is normal in other ways, talk to a doctor or nurse. Some changes in menstrual periods can be normal - but only a doctor can help determine the cause of irregular, heavy, painful periods, or no periods at all.

Cramps, PMS, and Pimples
Some women may notice physical or emotional changes around the time of their periods. Menstrual cramps are pretty common - in fact, more than half of all women who menstruate say they have cramps during the first few days of their periods. Doctors think that cramps are caused by prostaglandin, a chemical that causes the muscles of the uterus to contract.
Depending on the woman, menstrual cramps can be dull and achy or sharp and intense, and they can sometimes be felt in the back or the thighs as well as the abdomen. These cramps often become less uncomfortable and sometimes even disappear completely as a girl gets older. In the meantime, many girls and women find that over-the-counter pain medications (like acetaminophen or ibuprofen) can relieve cramps, as can taking a warm bath or applying a warm
heating pad to the lower abdomen. Exercising regularly throughout the monthly cycle may help lessen cramps, too. If these things don't help, ask your doctor for advice.
Some girls and women find that they feel depressed or easily irritated during the few days or week before their periods. Others may get angry more quickly than normal or cry more than usual. Some women crave certain foods.
These types of emotional changes may be the result of premenstrual syndrome (PMS). PMS is related to changes in the body's hormones. As hormone levels rise and fall during a woman's menstrual cycle, they can affect the way she feels, both emotionally and physically. Some women, in addition to feeling more intense emotions than they usually do, notice physical changes along with their periods - some feel bloated or puffy because of water retention, others notice swollen and sore breasts, and some get headaches. PMS usually goes away soon after a period begins, but it can come back month after month. Doctors recommend that women with PMS try to exercise to help feel better. And some women notice that restricting caffeine intake may help relieve PMS.
It's not uncommon for women to have an acne flare-up during certain times of their cycle; again, this is due to hormones. Fortunately, the pimples associated with periods tend to become less of a problem as girls get older.
Periods shouldn't get in the way of exercising, having fun, and enjoying life. If you have questions about pads, or coping with periods, ask your family physician. You also can search online for health-related websites with answers to some of your most personal questions. (AAFP)
---

Detecting and Dating a Pregnancy

If a menstrual period is a week or more late in a woman who usually has regular menstrual periods, she may be pregnant. Sometimes a woman may guess she is pregnant because she has typical symptoms. They include enlarged and tender breasts, nausea with occasional vomiting, a need to urinate frequently, unusual fatigue, and changes in appetite.
When a menstrual period is late, a woman may wish to use a home pregnancy test to determine whether she is pregnant. Home pregnancy tests detect human chorionic gonadotropin (HCG) in the urine. Human chorionic gonadotropin is a hormone produced by the placenta. Results of home pregnancy tests are accurate about 97% of the time. If results are negative but the woman still suspects she is pregnant, she should repeat the home pregnancy test a few
days later. The first test may have been performed too early (before the next menstrual period is expected to start). If results are positive, the woman should contact her doctor, who may perform another pregnancy test to confirm the results.
Doctors test a sample of blood or urine from the woman to determine whether she is pregnant. These tests are very accurate. One of these tests, called an enzyme-linked immunosorbent assay (ELISA), can quickly and easily detect a low level of human chorionic gonadotropin in the urine. Some tests can detect the very low level that is present about 1� weeks after fertilization
(before a menstrual period is missed). Results may be available in about half an hour. During the first 60 days of a normal pregnancy with one fetus, the level of human chorionic gonadotropin in the blood approximately doubles about every 2 days. Measurement of these levels during the pregnancy can be used to determine whether the pregnancy is progressing normally. After pregnancy is confirmed, the doctor asks the woman when her last menstrual period was. Pregnancies are conventionally dated in weeks, starting from the first day of the last menstrual period. The doctor calculates the approximate date of delivery by counting back 3 calendar months from the first day of the last menstrual period and adding 1 year and 7 days. Only 10% or fewer of pregnant women give birth on the calculated date, but 50% give birth within 1 week and almost 90% give birth within 2 weeks (before or after the date). Delivery between 3 weeks before and 2 weeks after the calculated date is considered normal.
Ovulation usually occurs about 2 weeks after a woman's menstrual period starts, and fertilization usually occurs shortly after ovulation. Consequently, the embryo is about 2 weeks younger than the number of weeks traditionally assigned to the pregnancy. In other words, a woman who is 4 weeks pregnant is carrying a 2-week-old embryo. If a woman's periods are
irregular, the actual difference may be more or less than 2 weeks. Pregnancy lasts an average of 266 days (38 weeks) from the date of fertilization (conception) or 280 days (40 weeks) from the first day of the last menstrual period if the woman has regular 28-day periods. Pregnancy is divided into three 3-month periods, based on the date of the last menstrual period. They are called the 1st trimester (0 to 12 weeks of pregnancy), 2nd trimester (13 to 24 weeks), and 3rd trimester (25 weeks to delivery).
If a woman and her doctor cannot confidently calculate when she became pregnant based on her menstrual period, ultrasonography may be performed to measure the fetus and thus establish the date. For the most accurate measurements, ultrasonography is performed during the first 12 weeks of a pregnancy. An accurate date helps doctors determine whether the pregnancy is progressing normally.
(AAFP)