What does ovulate mean in pregnancy
Calculating, Timeline, Pain & Other Symptoms
What is ovulation?
Ovulation is a phase in the menstrual cycle when your ovary releases an egg (ovum). Once an egg leaves your ovary, it travels down your fallopian tube where it waits to be fertilized by sperm. On average, it happens on day 14 of a 28-day menstrual cycle.
Ovulation and your menstrual cycle
The process of ovulation begins when your hypothalamus (a part of your brain) releases gonadotropin-releasing hormone (GnRH). GnRH causes your pituitary gland (a gland in your brain) to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
Between days six and 14 of your menstrual cycle, FSH causes follicles (small sacs of fluid in your ovaries that contain a developing egg) in one ovary to begin to mature. During days 10 to 14 of the cycle, only one of the developing follicles forms a fully mature egg. Around day 14 in the menstrual cycle, a sudden surge in LH causes the ovary to release this egg. This is ovulation. After ovulation, the hormone progesterone rises which helps prepare your uterus for pregnancy.
Ovulation, conception and pregnancy
Once ovulation occurs, your egg travels through your fallopian tube. It’s in your fallopian tube that your egg meets sperm for fertilization. If conception occurs (sperm fertilizes your egg), the fertilized egg travels down to your uterus. After about a week, the fertilized egg (now a blastocyst) attaches to the lining of your uterus. This is called implantation. Release of the hormones estrogen and progesterone causes the endometrium to thicken, which provides the nutrients the blastocyst needs to grow and eventually develop into a baby. As cells continue to divide — some developing into the fetus, others forming the placenta — hormones signal your body that a baby is growing inside your uterus. This also signals your uterus to keep its lining, which prevents you from getting your period. Not getting a period is usually the first sign you’re pregnant.
When does ovulation occur?
In an average 28-day menstrual cycle, ovulation occurs about 14 days before the beginning of your next menstrual period. The exact timing varies — your cycle length may be longer or shorter. You may find it helpful to track your menstrual cycle using an app on your phone or a calendar. This can help you determine when ovulation is most likely to occur. Most people will have a period 14 to 16 days after ovulation, regardless of the length of their overall cycle.
How many hours does ovulation last?
An egg only survives 12 to 24 hours after ovulation. If sperm doesn’t’ fertilize the egg, your body reabsorbs it. Unlike your egg, sperm can survive for several days in your body.
How do I know I’m ovulating?
Pinpointing ovulation can be tricky. There are several methods people use to track their menstrual cycle and estimate when ovulation occurs. Since each method has its drawbacks, it’s always best to use more than one for the most accurate answer.
Menstrual cycle
Ovulation happens at around the midpoint of your cycle if you have a 28-day cycle (day 14). However, a “normal” cycle is anything between 21 and 35 days, so this means ovulation is unique to your menstrual cycle. Keep track of your cycle on paper or on an app on your phone for several months. Take note of any unusual symptoms. Most people ovulate 14 days before their period begins, regardless of cycle length.
Calendar method
People using the calendar method to predict ovulation, analyze six months of menstrual cycles to determine when they’re fertile. To calculate when you may be ovulating, you find your shortest cycle and your longest cycle in a six month period. You subtract 18 days from your shortest cycle and 11 days from your longest cycle. These two numbers give you the days in your cycle you’re most fertile. For example, if your cycle lengths are 31 and 18, your fertile time is day 10 to 20 of your cycle.
Cervical mucus
Cervical mucus is a vaginal fluid produced by your cervix. Your cervical mucus goes through stages during your menstrual cycle. Your cervical mucus is thick, white and dry before ovulation. Just before ovulation, your cervical mucus turns clear and slippery (like egg whites). This consistency makes it easy for sperm to swim up to meet your egg.
Basal body temperature
Your body temperature increases slightly during ovulation (typically about 0.5 to 1 degree). Take your temperature every morning using a digital thermometer meant specifically for measuring basal body temperature. This method only works if you take your temperature before you get out of bed and before you eat/drink. Record your results for several months and note what day of your cycle a temperature increase occurs.
Ovulation kits
Ovulation kits work similarly to at-home pregnancy tests because you pee on an indicator strip in the comfort of your own home. They work by detecting LH (luteinizing hormone) in your pee. LH is the hormone that surges before ovulation. A positive result means you’re about to ovulate (usually within 36 hours).
What are the symptoms of ovulation?
Every person is different and not everyone has signs of ovulation. In those that do, the most common symptoms are:
- Tender breasts.
- Bloating.
- Minor pelvic or abdominal pain.
- Light bleeding or spotting.
- Changes in the position and firmness of your cervix.
- Increased sex drive.
- Heightened sense of smell, taste or sight.
- Mood changes.
- Appetite changes.
How many days during ovulation can you get pregnant?
Even though your egg only lives for 24 hours, sperm can live in your uterus for between three and five days. This means you can get pregnant from having sex from about five days before ovulation to one day after ovulation. If pregnancy is your goal, it’s better to have sperm already in your body when you ovulate. The highest probability of conception occurs when intercourse takes place one to two days before ovulation and on the day of ovulation.
Is pain during ovulation normal?
Yes, many people experience ovulation pain. Ovulation pain (or mittelschmerz) is cramping or pelvic pain that happens around ovulation. You typically feel the pain in your lower abdomen and pelvis, in the middle or on one side. Ovulation pain may happen when an egg bursts from a follicle (the sacs in your ovaries that contain eggs). It can even cause light bleeding.
Pain during the time of ovulation may also be caused by a medical condition, so it’s best to contact your healthcare provider to be sure the pain isn’t something more serious.
What happens if I’m not ovulating?
Certain health conditions or life events may affect ovulation or cause you to stop ovulating. Some of these are:
- Breastfeeding (chestfeeding) or hyperprolactinemia.
- Menopause.
- PCOS (polycystic ovary syndrome).
- Primary ovarian insufficiency.
- Amenorrhea from things like high or low body fat, excessive stress or fatigue or excessive exercise.
If your period is irregular or you go months without a period, you may have not be ovulating. Contact your healthcare provider if this is the case so they can rule out any serious conditions.
Do you still ovulate if you’re on birth control?
No, if you’re taking birth control pills or other hormonal contraception as directed, you shouldn’t ovulate. Keep in mind, this is only the case if you’re using pills, patches, IUDs or other devices exactly as prescribed. The hormones in birth control work by stopping ovulation and thickening cervical mucus (which makes it harder for sperm to swim).
Can you ovulate but not get your period?
Yes. You can ovulate but not get your “period.” Technically, if you’re ovulating regularly, you should also get your period regularly. However, it’s possible to get your period without actually ovulating and to ovulate but not have a true period.
Can medicine help you ovulate?
Yes, there are fertility medications to induce ovulation. Talk to your healthcare provider about your symptoms and goals, such as if you wish to become pregnant. They can work with you on the best treatment based on your condition.
A note from Cleveland Clinic
Ovulation is a process that occurs during your menstrual cycle. The exact timing of ovulation varies from person to person and even from cycle to cycle. Without ovulation, it’s hard for you to get pregnant or have regular menstrual periods. There are many methods available to help you predict ovulation. Knowing when you ovulate can help you either achieve a pregnancy or avoid a pregnancy. There are several health conditions that affect ovulation. Contact your healthcare provider if you’re concerned that you’re not ovulating.
When do I ovulate? Ovulation Symptoms, and More
Top things to know about ovulation
Your eggs live in sacs in your ovaries, called follicles
Follicles need the right conditions to grow and release their egg: your environment, health, and behaviors all play a role
To know when you ovulate, you can track your cycle, cervical fluid, basal body temperature, and/or take ovulation tests
Ovulation is sometimes associated with ovulation bleeding or ovulation pain
What is ovulation?
Ovulation is the release of an egg from your ovary, into your fallopian tube. It typically happens about 13–15 days before the start of each period (1). Like your period, the timing of ovulation can vary cycle-to-cycle, and you may have the odd cycle where you don’t ovulate at all.
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Understanding how ovulation works can be a powerful tool for your health
It’s common that people are introduced to the topic only after they have trouble becoming pregnant. But having a grasp on the process can give you insight into more than fertility. You’ll better understand any hormonally-influenced changes to your body around that time, and learn what factors might affect the timing of your ovulation (like stress), and why.
Research has found that in the global north, we ovulate roughly 400 times throughout our lifespan (2). This number is influenced by the use of contraceptives (many of which block ovulation), time spent pregnant and breastfeeding, and any behaviors or health conditions that affect the reproductive hormones (e. g. eating disorders, PCOS). Prehistorically, women would have ovulated less than half as often (3).
If conditions aren’t right, ovulation won’t happen
The development and release of an egg each cycle occurs in response to the intricate ups and downs of your reproductive hormones. Ovulation (and the menstrual cycle as a whole) is impacted by energetic, nutritional, emotional, and socioeconomic factors.
Short-term factors like jet lag, seasonal changes, stress, and smoking can have an effect, as well as longer-term factors like PCOS and thyroid disorders (4–8).
The basics of how ovulation works
Tiny eggs develop in sacs called follicles in your ovaries. Follicles develop for several months before they are ready to release their egg, (estimated at >175 days, or >~6 cycles) (9, 10). At any given time, there are follicles at several stages of development in your ovaries (10).
Early scientists once mistook the follicle for the egg itself
Follicles undergo incredible changes leading up to ovulation, developing many parts and layers, each with their own functions. Most follicles, though, will never reach ovulation, dying off at different phases of development or pre-development.
At the beginning of each menstrual cycle, a few (around 10) developing follicles are considered candidates for that cycle’s ovulation (11). By about midway through the follicular phase, one follicle becomes dominant.
Just like a superstar athlete being selected from the pack, all resources then go to preparing that single follicle, and the other potentials die off.
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When the follicle is ready, it releases its egg. The egg travels out of the ovary and is taken up by the fallopian tube (the two aren’t actually attached—think of the end of the fallopian tube collecting the egg from the abdominal cavity). After its release, the egg has about 12–24 hours to be fertilized by sperm in the fallopian tube. If the egg isn’t fertilized within this short window, it begins to degrade. If it is fertilized, it travels to the uterus over the following 6-12 days, to possibly implant for pregnancy (12, 13).
All of these events are driven forward by the cyclical changes in your reproductive hormones. Hormones control the selection and development of your follicles, the release of each egg, and the preparation of your uterus for possible implantation.
This first part of the cycle is called the follicular phase (now you know where it gets its name).
How do your brain and hormones interact with ovulation?
The brain-ovarian connection that controls follicle development and ovulation is called the hypothalamic-pituitary-ovarian axis, or HPO Axis.
Before ovulation
The brain produces continuous bursts of follicle-stimulating hormone, or FSH, throughout your cycle. FSH does exactly what it’s named for—it stimulates follicles to develop (2). As follicles grow, they produce estrogen.
As a dominant follicle is selected and grows (days 6–9 of the cycle), estrogen begins to spike (10).
A follicle becomes dominant at about 10mm in diameter, and typically grows to be about two centimeters in diameter (and up to about 3.3cm) (14–17). That’s about the size of a grape, or a hazelnut with its shell on.
Ready for release
When the amount of estrogen reaches its upper threshold, the egg is ready for release. The brain then produces a surge of luteinizing hormone (LH), triggering ovulation. The release of the egg from the follicle and ovary happens about 24 hours later (10–12 hours after LH peaks) (13, 17). The follicle uses enzymes to degrade its own wall and form an opening, allowing the release of the tiny egg from its center (18).
At the end of the fallopian tube, a finger-like structure swells with blood to grab and usher the egg in. Meanwhile, the egg has been undergoing its own changes to prepare for possible fertilization.
The pre-ovulatory follicle is the primary source of estrogen in the body. The dominant follicle is the source of more than 90% of the estrogen production in the pre-ovulatory period (19).
Take a look at the hormones graph. You’ll see estrogen, in blue, starts low and begins to spike midway through the follicular phase.
After ovulation
The egg may be on its way, but the follicle’s job is far from over. Luteinizing hormone transforms the large estrogen-making follicle into a progesterone-making machine (10).
This new progesterone producer (which also produces estrogen) is called the corpus luteum, or “yellow body” in Latin (because it’s yellowish in color). A new corpus luteum is made every cycle in which ovulation occurs. If ovulation doesn’t happen, you won’t get that surge in progesterone at all.
If the egg isn’t fertilized by sperm and then implanted in the uterine lining (after traveling down the fallopian tube, which takes several days), the corpus luteum begins to degrade, and hormone levels drop, triggering your period (20). If pregnancy does happen, the corpus luteum provides enough progesterone for your pregnancy to develop, until the placenta can take over (21).
Look at the hormones just after ovulation. Levels of estrogen drop slightly, and then progesterone (and estrogen) start to rise. If there is no hormonal signal that pregnancy has begun, they begin to drop again midway through the luteal phase, eventually triggering the period.
Your ovulation is not a clock
Any factors that influence the hormonal pulsing in your brain can influence your ovulation. Environmental and internal factors like stress, diet, and exercise changes can lead your ovulation to happen slightly earlier, or later, or not at all. Your period may then come earlier or later as well, and be lighter or heavier.
Your follicular phase is considered “plastic," compared to your luteal phase
That means it can commonly change in length, from cycle to cycle. If you know the length of your typical luteal phase (most often 13–15 days) you can count backward to get an idea of when you ovulated. Changes in the length of your cycle are usually pinpointed in the follicular phase—the time it takes a follicle to reach the point of ovulation.
It’s common not to ovulate on a regular basis when you first start menstruating. It’s also common to have irregular ovulation just after pregnancy and breastfeeding, and during the years approaching menopause.
Why does ovulation matter?
Not ovulating every once in a while may not be a concern, but if it becomes common, or if you stop ovulating altogether (and aren’t getting hormones in another way), serious health concerns can arise as a result.
The process of ovulation provides your body with much-needed levels of estrogen and progesterone—hormones that play a role well beyond fertility. They impact your bone density, heart health, metabolism, sleep quality, mental health, and beyond. Getting enough of them is important.
Anovulation during the fertile years is associated with osteoporosis, cardiovascular disease, and certain cancers later in life (22–25). Athletes with menstrual dysfunctions, for example, are significantly more likely to suffer from stress fractures (26).
How do I know if I’m ovulating?
As an adult, you are probably ovulating most of the time if your cycle is generally within range (that’s 24–38 days for adults, with fewer than 7–9 variance cycle-to-cycle, and a menstrual period of 2–7 days) (27). Cycles that are consistently outside of those ranges (they are long, short, or very irregular) can be an indication of anovulation, and a reason to talk to your healthcare provider.
To know if you’re ovulating (and when in your cycle it happens), you might try:Tracking your cycle length and regularity in Clue
Using ovulation urine tests, bought at your pharmacy
Tracking your physical signs of fertility for a few cycles, including your basal body temperature and cervical fluid
Have your healthcare provider check your hormonal profile (by testing a sample of your blood, taken during your mid-luteal phase)
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When do I take an ovulation test?You can test any time of the day, but it’s best to do it at the same time each day.
Ovulation test kits recommend picking a time when you haven’t urinated for 4 hours before testing or had excessive fluid intake. LH typically rises in the morning, between 4–8 am (29). If you test before it first rises, you may get a negative result that day, but you should still get a positive result the next day. If you’re trying to detect the earliest rise of LH, or if you're having trouble getting a positive result, try testing at different times throughout the day and see what works best for your body.
Article was originally published Nov. 23, 2017
Ovulation and pregnancy - methods for determining the relationship
Ovulation is the process of release of a mature egg from the follicle in the ovary. This phenomenon occurs once a month, around the middle of the menstrual cycle. The beginning of the cycle itself is counted from the first day of menstruation to the beginning of the next. And if we take the average menstrual cycle equal to 28 days, then ovulation with it will fall on about 13-15 days.
How to determine the onset of ovulation when planning a pregnancy
The physiological and hormonal cycles of each woman are strictly individual. In addition, many factors can influence the duration of a single menstrual cycle: stress, colds and other diseases, nutrition, taking various medications, etc. Therefore, at the very beginning of the cycle, it is impossible to say with certainty exactly when ovulation will occur. But there are several methods that can help you determine the exact start date.
- Special diagnostic complexes , which measure the content of a certain type of hormone (luteinizing hormone) in the urine. Such kits can be purchased at almost any pharmacy, and they always contain detailed instructions for use. A positive result with such a diagnosis usually indicates that ovulation will occur within the next 48 hours. But such complexes have not too high reliability, so a false positive result is possible.
- Basal temperature measurement . This method must be applied over several menstrual cycles in order to subsequently plot changes in basal temperature. It must be measured immediately after a night's sleep, at about the same time every day. Based on your individual schedule, it is possible to determine the onset of ovulation with a high degree of probability. Usually, about a day before ovulation, the basal body temperature decreases slightly, and the immediate release of the egg is accompanied by an increase in basal temperature by 0.3-0.6 ° C.
The relationship between ovulation and pregnancy
The period of release of the egg from the follicle and the following 24 hours is the optimal time for its fertilization and conception of a child. But, of course, not every ovulation ends in pregnancy. After all, a woman's body contains approximately 450 to 550 eggs, and all of them are already in her ovaries at the birth of a girl. This number determines the number of ovulations for her entire life, since once a month one of the eggs matures and becomes ready for fertilization.
An ovum that has left the ovary remains capable of fertilization for no more than a day, and spermatozoa retain this possibility for up to 72 hours. And it is during this period, that is, approximately 2-3 days before the onset of ovulation, that the efforts made by the couple have the highest probability of successful fertilization and the onset of pregnancy.
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Signs of ovulation
Women blink about 2 times more often than men.
OVULATION (from lat. ovum - egg) - release of a mature egg capable of fertilization from the ovarian follicle into the abdominal cavity; stage of the menstrual cycle (ovarian cycle). Ovulation in women of childbearing age occurs periodically (every 21-35 days). The frequency of ovulation is regulated by neurohumoral mechanisms, mainly gonadotropic hormones of the anterior pituitary gland and ovarian follicular hormone. Ovulation contributes to the accumulation of follicular fluid and thinning of the ovarian tissue located above the protruding pole of the follicle. The rhythm of ovulation , which is constant for every woman, undergoes changes within 3 months after an abortion, within a year after childbirth, and also after 40 years, when the body is preparing for the premenopausal period. Stops ovulation with the onset of pregnancy and after the extinction of menstrual function. Setting a deadline ovulation is important when choosing the most effective time for fertilization, artificial insemination and in vitro fertilization.
Signs of ovulation
Subjective signs of ovulation may be short-term pain in the lower abdomen. objective signs of ovulation are an increase in mucous discharge from the vagina and a decrease in rectal (basal) temperature on the day of ovulation with an increase in it the next day, an increase in the content of progesterone in the blood plasma, etc. Violation of ovulation is due to dysfunction of the hypothalamic-pituitary-ovarian system and can be caused by inflammation of the genitals, dysfunction of the adrenal cortex or thyroid gland, systemic diseases, tumors of the pituitary and hypothalamus , stressful situations. Lack of ovulation at childbearing age (anovulation) is manifested by a violation of the rhythm of menstruation by the type of oligomenorrhea (menstruation lasting 1-2 days), amenorrhea, dysfunctional uterine bleeding. Absence ovulation (anovulation) is always the cause of a woman's infertility. Methods for restoring ovulation are determined by the cause that caused anovulation, and require an appointment with a gynecologist and special treatment.
Some women experience peak sexual arousal on days 90,003 of ovulation 90,004. However, the use of a physiological method of contraception against pregnancy, based on sexual abstinence during ovulation , is especially difficult for young spouses, whose frequency of sexual intercourse reaches a fairly high level. In addition, with strong love excitement and nervous stress, additional ovulation can occur (especially with episodic, irregular intercourse), and then not one, but two eggs mature in one menstrual cycle. This should be remembered when choosing one or another method of contraception.
As soon as every healthy girl aged 11-15 years begins to menstruate, which is an indicator of her body's readiness for childbearing, then there are problems associated with counting the days of the menstrual cycle and the legitimate question why menstruation does not occur, or vice versa, why does not occur long-awaited pregnancy.
This makes a woman think and wait all the time, be in the dark about what happens to her every month. And so every month for decadesLength of menstruation and cycle
Ideal menstruation lasts 3-5 days and repeats every 28 days. However, for some women, this cycle takes 19 days or even less, while for others it lasts from 35 to 45 days, which is a feature of their body, and not a violation of menstrual function. The duration of menstruation also, depending on the organism, can vary within a week. All this should not cause alarm in a woman, but a delay of more than two months, called opsometry or more than six months - amenorrhea, should alert the woman and make sure to find out the cause with a gynecologist.
Length of menstrual cycle
The menstrual cycle is a complex physiological process that continues in women up to 45-55 years. It is regulated by the so-called sex centers located in the middle part of the diencephalon - the hypothalamus. The changes that occur during the menstrual cycle are most pronounced in the uterus and ovaries. In the ovary, under the influence of hormones produced by the ovarian follicles, partly by the adrenal cortex and testes, the main follicle, which contains the egg, grows and matures. The mature follicle ruptures and the egg, together with the follicular fluid, enters the abdominal cavity, and then into the fallopian tube. The process of rupture of the follicle and the release of a mature (suitable for fertilization) egg from its cavity is called ovulation , which, with a 28-day cycle, occurs most often between the 13th and 15th days.
Corpus luteum, estrogen, progesterone
A corpus luteum forms at the site of the ruptured follicle. These morphological changes in the ovary are accompanied by the release of sex steroid hormones - estrogens and progesterone. Estrogens are secreted by the maturing follicle, and progesterone by the corpus luteum.
The release of estrogen has two maxima - during ovulation and during the period of maximum activity of the corpus luteum. So, for example, if the normal estrogen content is about 10 µg/l, then during ovulation it is about 50 µg/l, and during pregnancy, especially towards the end of it, the estrogen content in the blood increases to 70-80 µg/l per due to a sharp increase in the biosynthesis of estrogens in the placenta.
Together with progesterone, estrogens promote the implantation (introduction) of a fertilized egg, maintain pregnancy and promote childbirth. Estrogens play an important role in the regulation of many biochemical processes, are involved in carbohydrate metabolism, lipid distribution, stimulate the synthesis of amino acids, nucleic acids and proteins. Estrogens contribute to the deposition of calcium in bone tissue, delay the release of sodium, potassium, phosphorus and water from the body, that is, increase their concentration both in the blood and in electrolytes (urine, saliva, nasal secretions, tears) of the body.
The secretion of estrogens is controlled by the anterior pituitary gland and its genadotropic hormones: follicle-stimulating (FSH) and luteinizing (LH).
Under the influence of estrogens in the first phase of the menstrual cycle, called folliculin, regeneration occurs in the uterus, that is, the restoration and growth of its mucous membrane - the endometrium, the growth of glands that stretch in length and become convoluted. The mucous membrane of the uterus thickens 4-5 times. In the glands of the cervix, the secretion of mucous secretion increases, the cervical canal expands, and becomes easily passable for spermatozoa. In the mammary glands, the epithelium grows inside the milk ducts.
In the second phase, called luteal (from the Latin word luteus - yellow), under the influence of progesterone, the intensity of metabolic processes in the body decreases. The growth of the mucous membrane of the body of the uterus stops, it becomes loose, edematous, a secret appears in the glands, which creates favorable conditions for attaching a fertilized egg to the mucous membrane and developing the embryo. The glands stop secreting mucus, the cervical canal closes. In the mammary glands, from the overgrown epithelium of the end sections of the milk ducts, alveoli arise, capable of producing and secreting milk.
If pregnancy does not occur, the corpus luteum dies, the functional layer of the endometrium is rejected, and menstruation occurs. Monthly bleeding varies from three to seven days, the amount of blood lost is from 40 to 150 g.
It should be noted that different women have a noticeable difference in the timing of ovulation . And even for the same woman, the exact timing of the onset fluctuates in different months. In some women, cycles are characterized by exceptional irregularity. In other cases, cycles may be longer or shorter than the average - 14 days. In rare cases, it happens that in women with a very short cycle ovulation occurs around the end of the period of menstrual bleeding, but still, in most cases, ovulation occurs quite regularly.
If, for one reason or another, ovulation does not occur , the endometrial layer in the uterus is thrown out during menstruation. If the fusion of the egg and sperm has occurred, then the cytoplasm of the egg begins to vibrate very strongly, as if the egg is experiencing an orgasm. Sperm penetration is the final stages of egg maturation. All that remains of a spermatozoon is its nucleus, where 23 chromosomes are densely packed (half the set of a normal cell). The sperm nucleus is now rapidly approaching the egg nucleus, which also contains 23 chromosomes. The two cores are slowly touching. Their shells dissolve and they merge, as a result of which they are divided into pairs and form 46 chromosomes. Of the 23 chromosomes of the sperm, 22 are completely analogous to the chromosomes of the egg. They determine all the physical characteristics of a person except gender. In the remaining pair from the egg there is always an X chromosome, and from the sperm there can be an X or Y chromosome. Thus, if there are 2 XX chromosomes in this set, then a girl will be born, if XY, then a boy.
Studies conducted at the National Institute of Environmental Medical Problems (North Carolina) showed that the time of conception in relation to the time of onset of ovulation depends not only on the actual conception of a child, but also on its gender.
The probability of conception is maximum on day of ovulation and is estimated at about 33%. A high probability is also noted on the day before ovulation - 31%, two days before it - 27%. Five days before ovulation the probability of conception is estimated to be 10% four days before ovulation - 14% and three days - 16%. Six days before ovulation and the day after ovulation, the probability of conception during sexual intercourse is very small.
Considering that the average “lifespan” of spermatozoa is 2-3 days (in rare cases it reaches 5-7 days), and the female egg remains viable for about 12-24 hours, then the maximum duration of the “dangerous” period is 6- 9days and the “dangerous” period corresponds to the phase of slow rise (6-7 days) and rapid decline (1-2 days) before and after the day of ovulation , respectively.