Safe Period Contraception Normal women of childbearing age menstruate once a month, from the beginning of the current menstrual period to the first day of the next menstrual period, known as a menstrual cycle. For contraceptive purposes, each menstrual cycle of a woman can be divided into the menstrual period, the ovulation period and the safe period. The safe period is a method of contraception that stops sexual intercourse during the ovulation period. It is a traditional method of contraception and was one of the commonly used contraceptive methods in Japan and abroad before the introduction of the pill and the IUD.
A woman’s ovulation date is usually about 14 days before the next menstrual period. The ovum is discharged from the ovary in the fallopian tube can survive for 1-2 days to wait for fertilization; the man’s sperm in the woman’s reproductive tract can be maintained for 2-3 days of fertilization ability, so in the days before and after the discharge of the ovum sexual intercourse is easy to conceive. To be on the safe side, we will ovulate 5 days before and 4 days after the day of ovulation, together with the day of ovulation, a total of 10 days is called the ovulation period. Because intercourse during the ovulation period is easy to conceive, the ovulation period is also known as the fertile period or the risk period.
The safe period is further divided into the pre-ovulatory and post-ovulatory periods. The period from the day your period clears to the day before ovulation begins is the pre-ovulatory period. The period from the first day after the end of ovulation to the day before the next menstrual period is the post-ovulatory period. The post-ovulatory safety period is safer than the pre-ovulatory safety period because some women are sometimes affected by environmental changes and mood swings to make ovulation earlier, so that the pre-ovulatory safety period will be shortened, and they do not know it, so that the pre-ovulatory safety period is not very safe. Ovaries in a menstrual cycle in two successive ovulation opportunities are very few, that is, after ovulation to the next menstrual period before this period of time will not occur again before the second ovulation, so, the safe period after ovulation is safer.
The key to using safe period contraception is to determine the date of ovulation of women. When the ovaries ovulate, there is generally no special feeling, even though some women may have lower abdominal pain, lumbago, breast swelling and mood changes and other symptoms, but these phenomena are not unique symptoms of ovulation, so they can not be used as the basis for ovulation. Menstruation and ovulation are cyclical changes, there is a close relationship between the two, if you grasp the pattern of change of the two, you can determine the date of ovulation through indirect methods.
There are many ways of determining the date of ovulation, but the methods that women can master on their own include projecting the date of ovulation according to the menstrual cycle, measuring the basal body temperature, and observing the secretion of cervical mucus.
Estimating ovulation by menstrual cycle
The method of projecting ovulation according to the menstrual cycle is also known as the calendar method. Both menstruation and ovulation are affected by endocrine hormones from the pituitary gland and ovaries and show cyclic changes. The length of the cycle is the same for both, 1 cycle per month, and ovulation occurs in the middle of the two menstrual periods. Women’s menstrual cycles vary in length, but the interval between the day of ovulation and the start of the next menstrual period is relatively constant, usually around 14 days. Based on this relationship between ovulation and menstruation, it is possible to predict ovulation according to the menstrual cycle.
The projection method is counting from the first day of the next menstrual period, counting down 14 days or subtracting 14 days is the day of ovulation, the day of ovulation and its first 5 days and the last 4 days together is called the ovulation period. This is the theoretical basis of the safe period contraceptive method.
For example, if a woman has a 28-day menstrual cycle and the first day of the current menstrual period is on December 2, then the next menstrual period is on December 30 (December 2 plus 28 days), and then subtracting 14 days from December 30, December 16 is the day of ovulation. The day of ovulation and the 5 days before and 4 days after it, i.e., December 11-20 are the days of ovulation.
Except for menstruation and ovulation, the rest of the time is the safe period. It is not necessary to use any contraceptive pills or devices for sexual intercourse during the safe period.
To predict ovulation by this method, the length of the menstrual cycle must first be known before the start date of the next menstrual cycle and the ovulation period can be predicted, so it can only be applied to women whose menstrual cycle has always been normal. For women with irregular menstrual cycles, the date of the next menstrual cycle cannot be estimated. Therefore, it is not possible to calculate the date of ovulation and the period of ovulation.
The calendar method of contraception is prone to failure. This is because some women can sometimes delay or advance ovulation due to health conditions, environmental changes and mood swings, and so on, so that the ovulation period projected according to the menstrual cycle is not correct.
According to foreign statistics, the failure rate of the calendar method of contraception is 14.4-47%. Therefore, this method is only suitable for people who have normal menstrual cycles, live together for a long time, and can correctly grasp the projected safe period. It is unreliable for people with irregular menstrual cycles, couples who are visiting relatives, and women whose living environment has changed.
Determination of ovulation using basal body temperature measurement
Basal body temperature is the temperature of the body measured before the body wakes up after a longer period of sleep and before any activity has taken place.
The basal body temperature of normal women of childbearing age varies cyclically, as does the menstrual cycle. This temperature change is related to ovulation. Under normal circumstances, a woman’s basal body temperature is low before ovulation and rises after ovulation. This is because the formation of the corpus luteum and the secretion of more progesterone after ovulation stimulate the thermoregulatory center of the hypothalamus, resulting in an increase in basal body temperature that lasts until the next menstrual period before it begins to fall. This change is repeated in the next menstrual cycle.
Record the daily measured basal body temperature on a temperature record sheet, and connected to the curve, it can be seen in the first half of menstruation body temperature is low, the second half of menstruation body temperature rise, this low before and high after the temperature curve is called biphasic temperature curve, indicating that the ovary has ovulation, and ovulation generally occurs in the process of body temperature rise before or from low to high rise. It has been suggested that the lowest point before the rise in temperature is the day of ovulation, but this is not the case in the majority of cases and is only seen in about 20% of women. Within 3 days of the rise in basal body temperature is the fertile period, and from the 4th day until the next menstrual period is the “safe period after ovulation”.
Basal body temperature measurement can only indicate that ovulation has occurred, but cannot predict when it will occur, so it can only determine the safe period after ovulation, not the safe period before ovulation. This problem can be solved if it can be combined with the calendar method and the cervical mucus observation method.
In most cases, basal body temperature measurement is very reliable for determining the safe period after ovulation, but sometimes irregular temperature curves are encountered, so the exact time of ovulation cannot be determined, in which case safe period contraception cannot be utilized.
How to measure basal body temperature correctly
A person’s body temperature is affected by the external environment and the body’s internal activities and fluctuations, in order to exclude these external and internal influences, so often 6-7 a.m. wake up before getting up the body temperature as the basal body temperature. Basal body temperature is the lowest body temperature in the human body during the day and night.
The method of measuring basal body temperature is simple, but the requirements are strict and need to be adhered to over a long period of time. Before measurement, you should prepare a thermometer and a record sheet to record the basal body temperature (if there is no such record sheet, you can also use a small square of paper instead), starting from the menstrual period, in the early hours of the morning before getting up every day, in the absence of speech and without any activity, put the thermometer in the mouth for 5 minutes, and then record the measured temperature on the temperature record sheet.
In order to improve the correctness of the measurement of basal body temperature, the mercury column on the thermometer should be dumped below 35℃ every night before going to bed, and it should be placed on the bedside table or next to the pillow, so that it can be taken at hand when it is used to minimize the activities. If you get up to get the thermometer, you will raise the basal body temperature and make the temperature value for the day meaningless.
For women who work mid-shift or night shifts, time your basal body temperature measurements to coincide with your first awakening 4-6 hours after each sleep.
Basal body temperature usually needs to be measured for more than 3 consecutive menstrual cycles to indicate the problem. If your menstrual cycle is regular, you will basically know the date of your ovulation after measuring your basal body temperature for several cycles.
In order to minimize the trouble, you can choose to start testing your temperature 3-4 days before the day of ovulation, and then just continue to test for another 3-4 days after the temperature rises, which means that you only need to measure your basal body temperature during the ovulation period for contraception purposes.
How to Record Basal Body Temperature Correctly
Correct recording of the measured basal body temperature on a temperature recording sheet can reflect the functioning of the ovaries.
If it is not recorded correctly, it loses its significance. The following is a graph of the basal body temperature of a normal woman of childbearing age during a menstrual cycle. As seen in the graph, the first half of the body temperature is low, and the second half of the body temperature rises, showing a typical biphasic body temperature curve. This type of temperature curve indicates that the ovary has the function of ovulation, and the junction of the high and low temperature curves is the ovulation date of the ovary. The coordinates of the vertical axis of the graph indicate the degree of body temperature, and each small frame is 0.1℃.
The horizontal axis coordinates indicate the date and the day of the menstrual cycle, and each small grid is 1 day. Starting from the first day of menstruation, the body temperature measured every day will be drawn with dots in the grid of the corresponding temperature record sheet until the day before the next menstruation, and finally the dots will be connected with a straight line in sequence, which will become the basal body temperature curve of one menstrual cycle.
The blacked-out part of the chart indicates the menstrual period. In case of cold, fever, diarrhea, insomnia, alcohol consumption, use of electric blankets, etc., the basal body temperature tends to be easily affected, which should be explained at the bottom of the table.
What is the purpose of measuring basal body temperature
Measuring the basal body temperature of normal women of childbearing age has an important use in medicine, it is a simple, practical, easy to learn and relatively reliable method of self-monitoring ovarian function. According to the change of basal body temperature, it can indirectly know the ovarian function of women, understand whether there is ovulation or not, predict the date of ovulation and luteal function. Measuring basal body temperature is generally used for the following purposes.
(1) Observation of ovarian function
In normal women of childbearing age, the basal body temperature curve is biphasic, i.e., it is low in the first half of the menstrual cycle and high in the second half, which indicates that the ovaries have a normal ovulatory function. If the basal body temperature shows a monophasic curve (no low in the first half of the menstrual cycle and high in the second half), this indicates that the ovaries are not ovulating.
(2) Diagnosis of early pregnancy
Measuring basal body temperature is one of the simplest and quickest ways to diagnose pregnancy. If a woman with a regular menstrual cycle suddenly stops menstruating and her basal body temperature rises and then does not fall again for more than 18 days, pregnancy can usually be diagnosed. This is because after ovulation, the follicle forms the corpus luteum, which secretes progesterone, which raises the body temperature. If the egg is fertilized and pregnancy occurs, the corpus luteum will continue to secrete progesterone, and so the body temperature will remain at a high level.
(3) Guidance on contraception
Measuring basal body temperature can tell a woman’s date of ovulation, allowing the use of safe-period contraception.
(4) Guidance on childbirth
Contrary to contraception, if one wants to have children, one should choose to have intercourse at the time of ovulation. Because the measurement of basal body temperature can determine a woman’s date of ovulation, it can be used to guide fertility. In particular, certain women who are less likely to become pregnant can increase their chances of conception by scheduling intercourse during ovulation.
Use of cervical mucus observation to determine ovulation
In the 1970s, two Australian doctors, Dr. John and Dr. Evelyn Billings, pioneered the cervical mucus observation method for determining ovulation, which is used as a guide for contraception, in accordance with the characteristics of cyclical physiological changes in women’s reproductive systems.
This method is known as the “Billings Method” and has been recommended by the World Health Organization. In recent years, the Billings Method has been widely used in more than 100 countries.
In September 1987, Mrs. Wilson of the American Family Foundation led a team to our country to promote this method and held a training course for teachers. Subsequently, the Tianjin Institute of Family Planning selected 300 women of childbearing age to use the Billings Method for contraception, and they observed more than 2,000 menstrual cycles of the subjects, with only three of them failing to use contraception.
Cervical mucus is produced by specialized cells in the cervical canal of the uterus, and the amount and nature of its secretion changes with ovulation and the menstrual cycle. During a menstrual cycle, there are three types of cervical mucus: non-fertile, fertile and highly fertile.
Infertile cervical mucus: This is the early mucus in the menstrual cycle, appearing after menstruation and lasting for about 3 days. At this time, the cervical mucus is small and thick, and the vulva is dry without wetness, and the mucus is not stained on the underwear.
Easily fertile cervical mucus: this mucus appears after the 9th-10th day of the menstrual cycle, with the development of follicles in the ovaries, estrogen levels rise, the cervical mucus gradually increases, thin, milky white. At this time, there is a wet feeling in the vulva.
Very fertile cervical mucus: a few days before ovulation, estrogen further increase, the cervical mucus contains more water, but also more clear like egg white, the viscosity of the smallest, smooth and elastic, with the thumb and forefinger can pull the mucus into a very long filament (up to 10 centimeters or more), when the vulva feels a clear sense of wetness. It is generally believed that the secretion is clear and transparent as egg white, and the day with the longest pulling degree is likely to be the day of ovulation, and 3 days before and after this day is the period of ovulation.
After ovulation, the corpus luteum forms and produces progesterone, which inhibits the cervical cells from secreting mucus, so the cervical mucus becomes less viscous and thicker again, and becomes the infertile type of cervical mucus until the next menstrual period. This change occurs again in the next menstrual cycle.
The cervical mucus method is used as a contraceptive for women with normal menstruation, as well as for women with irregular menstruation, menopausal women and breastfeeding women. If a woman with an IUD combines it with the cervical mucus method of contraception, it can reduce pregnancies with and without the IUD, thus providing a double insurance policy.
How do I observe changes in cervical mucus?
The application of the cervical mucus observation method to determine ovulation begins with training and guidance for contraceptive users. Observation of cervical mucus is required several times a day. Generally, one can use the opportunity after waking up, before taking a bath or before urinating to take mucus from the vaginal opening with a finger for examination, observe the appearance of the mucus on the finger, the degree of consistency as well as do a pulling reaction with the finger and other aspects of the examination. In this way, after more than 3 menstrual cycles of observation, you can grasp their own cervical mucus secretion pattern and ovulation period. Once the vulva is found to have a wet feeling and thick mucus has a tendency to become thinner, mucus can be drawn up to a few centimeters, should be considered to be in the fertile period (ovulation), until thin, transparent, can be drawn up to the peak of the mucus day after the fourth day, to enter the safety of the period after ovulation.
Changes in intravaginal cervical mucus are influenced by a variety of factors, such as severe intravaginal sensory leakage, douching the vagina, vaginal secretions during sexual arousal and postcoital mucus, and the use of intravaginal spermicidal drugs. If you are not sure about the nature of the intravaginal cervical mucus, it should always be regarded as ovulation and should not be taken for granted.
The use of cervical mucus observation method of contraception must be mastered after the change pattern of cervical mucus change can be used.
What you need to be aware of when using safe period contraception
Safe period contraception is a physiological contraceptive method, sex is carried out in a normal state, you can get satisfied with the sexy. But if you can not strictly master or improper use, it is easy to lead to failure.
The first step in using safe period contraception is to accurately determine the period of ovulation. At present, the three methods used to determine the ovulation period have their own advantages and disadvantages: the calendar method can be used to estimate the ovulation period and the safe period before and after ovulation. However, it is only applicable to women with normal menstruation, sometimes due to environmental changes and emotional changes to make ovulation early or delayed, so it is not accurate enough; measurement of basal body temperature method can determine the date of ovulation and the safe period after ovulation, can not be determined in advance of the safe period before ovulation, the method is more troublesome, the requirements are stringent, such as not in accordance with the provisions of the measurement of body temperature, can not be accurately determined the date of ovulation; the cervical mucus observation method can be determined and the safe period before and after ovulation, but not in advance. The cervical mucus observation method can determine the ovulation period and the safe period before and after ovulation, with higher correctness, but users must be trained and fully mastered before use. If these three methods are used in combination, they can maximize their strengths and avoid their weaknesses and achieve greater results.
At least one of the spouses can master the method of determining the ovulation period, and if they cannot master this method, they cannot use safe period contraception.
Safe-period contraception means stopping sexual intercourse during ovulation, which requires the close cooperation of the male partner, otherwise it cannot be used. Of course, the use of topical contraceptives during ovulation is also possible.