The fertile period is the period of time within the menstrual cycle when the woman can get pregnant. This is because while the man produces sperm all the time, the woman releases only one or two eggs once a month.

Besides taking into account when the egg is released, usually the calculation also considers the time that the sperm has to fertilize that egg, as they survive in the body for three to five days. Therefore, the fertile period is the six-day range that ends on the day of ovulation.

The fertile period usually occurs in the middle of the menstrual cycle of 14 days before the next menstruation.

The menstrual cycle causes a lot of changes in the body throughout its duration. During the fertile period and ovulation is no different: a woman may experience some symptoms. These occur:

Mild pain in the lower abdomen

It's a little pain that causes mild twinges in the lower abdomen, although not every woman realize it. It is hardly a sharp pain, is just a nuisance. That's because the egg breaks a structure that wraps within the ovary, and it is this rupture that can cause this little discomfort. So to feel that twinge in the pelvic area, chances to be ovulating.

Secretion similar to egg white

During the breeding period, it is common to see women increased vaginal discharge, which is similar to an egg white and half is elastic without strong odor. This is because the female body is prepared to fertilize and this secretion has the role of facilitating the arrival of sperm to the egg. Although it occurs throughout the cycle, it is more evident during ovulation. After this phase, the discharge tends to decrease.

increased libido

It is in the ovulation phase that female desire increases. After all, the body is physiologically ready to fertilize and automatically it is through a sexual relationship.

Not only is the libido increases, but the production of pheromones, substances that are exhaled by the body in order to attract and excite the opposite sex. The woman is also more sensitive, with the most acute sense of smell.

Increased body temperature

The fertile period is also normal basal temperature increase woman about half a degree. This can help those who are trying to conceive to identify the most fertile days, but you need to have the help of a thermometer. Many doctors who teach the candidates to get pregnant recommend measuring the temperature by placing the thermometer under the tongue before you get up in the morning, from the first day of the menstrual cycle. When the thermometer marking a higher temperature, probably this woman is in the fertile time.

Before calculating the fertile period it is important to know when hard time your menstrual cycle. Usually the first day of the cycle is the day that menstruation down. Therefore, the time interval between the start of each period is their menstrual cycle.

Knowing this, the process of calculation is quite simple:

1. Find out how long your menstrual cycle. If this number varies each month, to monitor the intervals for three months and then try to calculate an average.

2. Having in hand the duration of the cycle, subtract 14 from this number. This will make you discover the day of ovulation.

3. As the fertile period is the six-day range that ends on the day of ovulation, take the date from step 2, count five days back and you know your fertile period.

For example, if a woman has a 30 days cycle, their ovulation to occur on the 16th day, ie, her fertile period occurs between the 11th and 16th days of the menstrual cycle.Already a woman with 28-day cycle will ovulation on the 14th day of the cycle, so it is most fertile between the 9th and 14th days.Finally, women with cycles of 26 days ovulate on the 12th day of the cycle, ie, fertility is high between the 7th and 12th days of the cycle.

Women have shorter cycles ovulate earlier. This is because the menstrual cycle is divided into two phases:

These two periods are precisely divided by ovulation and while the follicular phase may vary from woman to woman, the luteal phase always lasts 14 days (so subtract 14 this account).

If the menstrual cycle is irregular, how to calculate the fertile period?

The regular menstrual cycle lasts considered between 25 and 30 days. A woman has cycles with different durations, but ranging between these time intervals are still considered regular.

To do the calculation in this case, just reach an average length of these cycles. For example, if a woman is between 27 cycles, 28 and 29 days, the average is 28 days long

Women with very long or very short cycles should be evaluated judiciously, because they often can not be ovulating or ovulate too early or too late, when the body is not prepared for it. In these cases it is important to seek a gynecologist.

Experts answer questions on the topic:

The fertile period is before or after menstruation?

How many days the fertile period lasts?

As is the fertile period who take birth control?

If I have intercourse in the fertile period, I can get pregnant?

There is the risk of becoming pregnant if I have sex outside of fertile period?

Gynecologist Joji Ueno, Doctor of Gynecology, Faculty of Medicine at USP and director and founder of the Clinic GERA

Gynecologist Renato Tomioka, member of the American Society of Reproductive Medicine (ASRM) and the Society of Gynecology and Obstetrics São Paulo (SOGESP) and director of clinical VidaBemVinda (SP)