The calculation of ovulation is essential for the purpose of conception and the prevention of unwanted pregnancies.
The period of ovulation fertility for a woman. Knowing exactly when ovulation occurs therefore increases the chances of getting pregnant.
For this reason, it is important to be familiar with the subject at every stage of childbearing age, to put it into practice both when you want a baby and when you want to avoid unwanted pregnancy.
Because it's important?
Calculating ovulation requires knowledge of the rhythms and times of one's body; in particular, it focuses on the functioning of the menstrual cycle. This method allows, in fact, to identify the most fertile days and to understand when conception is more likely, in case of sexual intercourse.
Ovulation and fertile period
To understand the calculation of ovulation some premises are necessary.
What is ovulation?
In each menstrual cycle, the most favorable days for conception coincide with ovulation and the period preceding it.
Generally, ovulation takes place in the middle of the cycle, so - if the woman has a regular 28-day menstrual cycle - it occurs 14 days before the next menstrual flow begins.
What Happens During Ovulation?
During ovulation, the egg cell which has reached maturation is released from the follicle that contains it and expelled from the ovary towards the uterine tube (or oviduct). Here it can be fertilized by a sperm of male origin.
Every woman is born with a limited supply of egg cells, which progressively diminishes over the years. Starting from puberty, ovulation is repeated every month, until the menopause is reached, around the average age of 50.
The interval between puberty and menopause is called the fertile age.
Calculation of ovulation: times and duration
Ovulation occurs approximately every 28 days. After the onset of menstruation, the egg cell takes an average of 14 days to reach adequate maturation and exit the ovarian follicle to reach the tube; this time interval coincides with the follicular phase. True ovulation therefore corresponds to the release of the oocyte from the ovary; the most fertile days coincide with those preceding this phase and with the very moment in which the egg cell enters the oviduct and begins its journey to reach the uterus.
The "fertile window" and the calculation of ovulation
Conception is only possible on certain days of a woman's menstrual cycle.
- The moment of maximum fertility coincides with the day of ovulation itself, that is when a mature egg is released from the ovary, moves along the fallopian tube and is available to be fertilized.
- The fertile period, however, is longer, considering that the egg cell expelled from the ovary manages to survive for about 24 hours, while the spermatozoa can remain viable in the female genital system up to 72-96 hours after intercourse.
Indicatively, therefore, the "fertile window" in which it is possible for the egg to be fertilized begins 4-5 days before ovulation and ends 1-2 days later.
- It should be noted that the probability of pregnancy increases significantly especially in two days before ovulation and on the day it occurs.
Outside the "fertile window", however, conception is less likely.
What happens after ovulation
After ovulation, the menstrual cycle is completed by the luteal phase, which runs from around the 16th to the 28th day; during this phase the inner wall of the uterus (endometrium) prepares to accommodate the egg, in case conception occurs. If the egg is fertilized, the resulting cell divides (blastula) and implants itself in the endometrium 3 or 4 days after reaching the uterine cavity, i.e. 6-7 days after sexual intercourse.
Conversely, if conception does not take place, starting from about the 28th day menstruation appears, with which the remains of the endometrium are expelled from the vagina.
How to calculate the day of ovulation
Consider the rhythm and length of the menstrual cycle. A good habit to adopt to evaluate the progress of your menstrual cycle - and clearly identify the day on which ovulation will occur - is to note monthly when your period begins.
NB: to calculate the duration of your cycle, the period of time that goes from the first day on which the menstrual flow appears to the day before the start of the next menstruation must be considered.
Ovulation occurs about two weeks before the next menstruation. If the menstrual cycle is repeated regularly every 28 days, ovulation will be around the 14th day (ie 14 days before the next menstruation) and the "fertile window" will begin on the 10th day.
NB: this is an illustrative reasoning and it is not possible to know with extreme certainty if the menstrual flow following ovulation will really arrive on the 28th day (in other words, the cycle does not always occur with the same interval of days ).
Whether the menstrual cycle is longer or shorter, it is important to consider that the first phase of the menstrual cycle (estrogenic) is variable and can undergo fluctuations, while the second phase (progestin) is more constant and lasts an average of 14 days.
Even if the duration of the menstrual cycle is different from the average of 28 days, therefore, the fertile period will always be 14 days before the arrival of menstruation and in the 4-5 days preceding it.
- The day of ovulation and the two days preceding it are the most fertile. In general, the most favorable days for conception are six: the day of ovulation and the 5 days preceding it. The likelihood of pregnancy increases, however, in the two days immediately preceding ovulation and on the day it occurs.
NOTE: : it should be remembered that the calculation of ovulation based on the date on which menstruation appeared is susceptible to error, even for women with regular menstrual cycles. In fact, in some months ovulation can be unexpectedly anticipated or delayed compared to the expected day, making the simple numerical calculation useless.
When to have sex
Menstrual cycles can vary and are not always as regular as clockwork; therefore, it can be difficult to predict exactly when ovulation should occur. In addition, the chances of getting pregnant depend on many variables that can "offset" the "fertile window", such as age, general health and lifestyle.
Therefore, regular sexual activity is important for conception. In particular, having intercourse every 2 or 3 days, allows you to cover as much as possible the entire presumed fertile period and increases the probability of becoming pregnant.
Signals not to be underestimated
Women with an irregular menstrual cycle, which varies from month to month, cannot rely solely on calculating days to figure out when ovulation will occur.
In these cases, it is important to combine other methods to recognize the fertile period, such as recognizing the signals of your body.
In fact, during the ovulatory phase, changes occur that can act as indicators (see ovulation symptoms):
- The breasts become tense and sometimes painful;
- The lower abdomen hurts and swells;
- Sexual desire increases;
- The senses and reflexes become more active;
- Vaginal secretions become more abundant, transparent and stringy.
Other methods of recognizing ovulation
In addition to the calculation of ovulation, to understand when the "fertile window" is approaching, it is possible to resort to other methods, which include:
Observation of changes in cervical mucus. A system for recognizing when ovulation is about to occur is based on observing the quantity and appearance of vaginal secretions.
Due to the effect of estrogens, in the pre-ovulatory period the production of cervical mucus increases, which becomes evident with transparent losses. When ovulation is imminent, the secretions become very abundant and viscous and elastic in consistency, similar to egg white. From this change, ovulation could occur on the same day or within approximately 24-36 hours. In practice, the cervical mucus "prepares the ground" for the eventual fertilization of the mature egg cell, as it facilitates the passage of spermatozoa through the vaginal canal and promotes their survival. The secretions retain these characteristics until ovulation is complete, then they become thick, sticky and diminish or disappear.
NB: it is necessary to consider that there are some conditions, such as the presence of infections or polycystic ovary syndrome, which can alter the consistency of the mucus and make it difficult to observe for procreative purposes.
- Record your basal temperature daily. To identify fertile days, you can use the daily measurement of the basal temperature in the morning, when you are just awake. It will be observed that, every month, there is a morning when this parameter increases by about 0,2-0,5 ° C and remains constant for a few days until the next menstruation. This is explained by the fact that the basal temperature tends to increase immediately after ovulation due to the effect of progesterone. The rise in basal temperature is also preceded by a slight decrease in it; the last value, recorded before the increase in basal temperature, corresponds to the day of ovulation. By recording these data on a graph or on a table and observing the similarities in the trend of the basal temperature, therefore, it is possible to determine in which period of each month ovulation occurs. However, it should be remembered that basal temperature can rise due to other factors, such as restless sleep, alcohol or hot drink, hormonal imbalances, severe stress and fever.
- Use ovulation tests. Ovulatory sticks warn you when you are going through the fertile phase by measuring hormone levels in the urine. The test should be repeated for a few days, starting from the date on which ovulation is most likely to occur. When a positive result is found, it means that the luteinizing hormone (LH) has reached a high concentration, so the ovulatory phase is imminent and you are in the most fertile moment of your cycle. Therefore, if you want to become pregnant, it is possible to have unprotected intercourse starting from the same day in which the test is positive.
Other articles on 'Ovulation Calculator'
- Ovulation and Conception
- Ovulation and Fertility: Symptoms, Calculation, Ovulation Test
- Ovulation Disorders and Ovulation Control
- Painful ovulation - Mittelschmerz