FAQ: The Menstrual Cycle

Detailed Question: 

Common Questions About The Menstrual Cycle



Why Is My Period Late?

First and foremost a late period can signal the onset pregnancy. For some women, this is an exciting time if they have been trying to become pregnant. For others who are not intending pregnancy, a late period is a very stressful time. If a female has engaged in unprotected sex, sex during which the condom broke, activities where sperm have come into contact with her vagina, and her period has not come on its normal date, then there is a chance she may be pregnant. The only sure way to find this out is by taking a pregnancy test, either at home or at the doctor's office.


A second cause for a late period could be an STI, such as Pelvic Inflammatory Disease, which can cause such symptoms as "disruptions of menstrual periods." Because of this, it is important to also get tested for STIs. People who are sexually active should get tested after every new partner, unless they used sufficient protection.

Many people want to know just how late a period can be before they should worry, but this is not an easy question to answer, since there is so much variation among women. One suggestion is for females to get in touch with their bodies by keeping track of their menstrual cycle lengths for a long period of time. This involves writing down on a calendar their start and stop dates each month. This way, when the question of a late period arises, women can refer to what their cycles have been like in the past and see if there really is a reason to be concerned.

A final thought to keep in mind is that stress can often delay a period, so stressing out over a late period is a real catch-22. If a woman's period is late, she should calmly consider the fluctuation of her past start dates, what behaviors she has engaged in, and then decide if she needs to take a pregnancy test or get examined for STIs. In either case, these simple tests can be done at a doctor's office, where women can also get more specific information for their personal situations.



Why Is My Period Irregular?

Just like a late period, an irregular period may also be an indicator of an STI, pregnancy, or other changes in a female's body.

One important thing to keep in mind - for young women especially - is that it may take a significant amount of time after menarche (first menstruation) before menstruation is regular. One quote from a female SexInfo reader portrays exactly how erratic and even frustrating this process can be:

"I am 19 years old. When I was 13, I got my first period. Then I did not get another period until I was 15. Then my period was regular until I was 16, when I began to miss it for months at a time. Most recently, I missed it for about a year, but I got it a week ago. I have had at most, 15 periods in my life! The doctors say that there is nothing wrong with me, and that I just need to eat better and exercise. My question is, if there is nothing wrong with me, then why do I miss my period so often?"

Understanding how common this situation is may help some women to quell their own worries. This is an ordinary - granted annoying - aspect of being a woman. However, it must be stated that for sexually active females, an irregular period may not always be ordinary, as this type of change can be an indication of pregnancy. 

Some women are so bothered by an irregular period that they may consider talking with a doctor about ways to achieve a regular cycle. There are several ways to shorten (or even completely stop) your period. Some women like getting their period every month, as proof that they are not pregnant. However, they would prefer it to be shorter than the typical seven day cycle. Some studies have shown that masturbating during your period may make it shorter, while also relieving cramping and discomfort. Most hormonal contraceptive methods, such as birth control pills or IUDs will give you a steady cycle, while reducing the amount of time that each period lasts.

If a woman is interested in completely stopping her period, there are several options available. First of all, there are brands of birth control pills that can be taken for months at a time without having a period. The most popular version of this type of pill is Seasonale; but a health care provider will be able to prescribe generic brands as well. Another option is using a low-dose or progestin only birth control method, such as Implanon or Depro-Provera. Although there are no guarantees that your period will disappear completely, menstruation is usually very minimal on this type of birth control, and it often becomes nonexistent. Keep in mind that these methods only temporarily eliminate your period, and once you stop taking the birth control, your cycle will regulate again. We recommend seeing a doctor to go over the various options. This allows each woman to decide which method would be best for her.


How Are Sexual Activity and the Menstrual Cycle Related?

Sometimes people are curious about the ways that menstruation might either inhibit or enhance sexual activity, and/or whether or not sexual activity is possible during menstruation. While some women find that they are more sexually excited during their menstrual periods, this is not true for most women; and in fact there is considerable variability in women's sex drives across the span of the menstrual cycle. The relationship between female sex drive and menstruation is a popular area of research, and yet there have not been conclusive findings about when women are most sexually excited.


Some evidence suggests that women are more sexually excited during the time of ovulation, which is the most fertile phase of the menstrual cycle: It is the time at which the ovary releases an egg - about 14 days before the start of the next menstrual period. At this time, hormone levels of estrogen and testosterone are at their highest peak of the cycle, and it is this surge of hormones that may lead many women to report higher interest in - and frequency of - sexual activity. From an evolutionary standpoint, this finding seems to make sense, since an increased sex drive at the time of ovulation would promote the chances for conception and reproduction.


However, many women feel most sexually excited just before, during, or just after their period, which could possibly be attributed to varying social, cultural, and psychological factors. For some females, menstruation is a time when they may not care to engage in sexual activity for reasons such as cleanliness or discomfort. Consequently, a woman may feel more excited right before her period, in anticipation of the upcoming period of sexual inactivity, or especially interested just after, having not engaged in sexual activity for a time. Along this same line of thought, people have speculated that when women are sexually excited during menstruation, it is because the time of sexual inactivity that often accompanies their period makes them desire or miss being sexually active even more so than normal.


It is still up for debate whether a woman's sexual excitement is most influenced by hormone levels, psychological processes, or other factors. Although there are certain times during the cycle when a woman may be more likely to engage in sexual activity, it is ultimately individual preference that determines when a woman feels most sexually excited. It is crucial to keep in mind that even though pregnancy is least likely to happen when a woman is menstruating, it is still possible; and this is why a form of contraception should always be used.


A second issue concerning sexual activity and menstruation is the confusion between menstrual bleeding and bleeding for other reasons, such as rough manual stimulation or intercourse. To avoid bleeding from sexual activity, women should encourage their partner to be very gentle, use sufficient lubrication, and do any necessary nail trimming to avoid scratching the sensitive vaginal tissue.


How Are Weight and the Menstrual Cycle Related?

Sudden changes in a woman's body, including changes in diet, exercise, weight and stress, may lead to changes in her menstrual cycle. If a woman has a variation in her normal diet and/or exercise, and then added stress on top of that, she might miss her period, get it early, or get it for longer. Typically, weight loss can cause the menstrual flow to lighten; however, fluctuations from cycle to cycle are normal throughout a woman's life. Weight gain is one of the symptoms of Premenstrual Syndrome (PMS) as defined by the Food and Drug Administration. This type of weight gain - sometimes referred to as "bloating" - usually occurs during the second half of the menstrual cycle (14 days or more after the first day of the period), and is absent for about 7 days after a menstrual period ends (during the first half of the menstrual cycle). It is also normal for women to gain a little weight as they grow older, especially after menopause. Maintaining a weight that is within the Body Mass Index via exercise and proper diet can not only help women maintain a positive body image, but keep her body, mind and menstrual cycle healthy and regular as well.





Last Updated: 6 June 2012


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