How many days do sperm live in different environments? How does the process of conceiving a child occur?
The lifespan of sperm is an important and pressing issue for those who have plans for procreation, as well as for those who are not yet ready for such an important step.
Sperm generation
The scientific name for the generation of sperm is spermatogenesis. Sperm are born and live in the testicles of adult men. The duration of sperm formation is about 74 days. During this period, they go through the stages of obtaining their set of chromosomes, growing a tail, forming a motor apparatus and assembling DNA for survival in an unfavorable environment for them, which for them is the female body. After ripening, they accumulate at the outlet of the vas deferens.
Sperm that are mature and ready for fertilization live in the male body for up to a month.
With prolonged abstinence, sperm ages, after which they become unsuitable for fertilization. Therefore, regular sex life is necessary to renew the semen.
During active sexual life, when more than 4 ejaculations occur in 12 hours, there may not be enough mature cells for fertilization. To increase the likelihood of conception, it is necessary to abstain from sexual intercourse for a couple of days to produce and mature new sperm.
While in the male body, sperm are inactive. Their activity occurs when they interact with prostatic juice during the process of ejaculation. After peristaltic muscle contractions, male cells are pushed through the vas deferens into the urethra. There they are mixed with the secretions of the prostate and the contents of the seminal vesicles. This produces seminal fluid, which feeds sperm with glucose and fructose, increases their mobility, and protects against increased acidity in the vaginal environment.
Semen contains approximately 5% of sperm of the total volume of secreted fluid.
After ejaculation, a new batch immediately arrives to replace the ejected sperm, which makes it possible for a healthy man to impregnate a woman with repeated ejaculations.
Lifetime in a woman's body
The movement of gametes occurs due to flagella, they are also called the tails of male reproductive cells. They can move at speeds of up to 0.1 mm per second.
During ejaculation, approximately 250 million sperm are released in 2-5 ml of seminal fluid. For the female body, sperm is a foreign body with which her immune system begins to fight. Therefore, the environment in the vagina has a destructive effect on sperm, and seminal fluid protects against the effects of acids with which the female immune system tries to cope with strangers.
To achieve the final goal, the gametes need to travel a distance of approximately 20 cm, which they cover by moving against the movement of the fluid.
That part of the sperm that did not immediately die in the vagina enters the uterus through the cervical canal of the cervix. To do this they will need 1-2 minutes. At this stage, many male cells die due to the aggressive environment for them in the cervical canal. If a woman experiences an orgasm at this time, the mucous membrane becomes less viscous, the muscular wall of the uterus contracts and a retracting effect occurs, helping the sperm to penetrate further. Therefore, with simultaneous orgasm or achieving it immediately after ejaculation, the likelihood of conception increases.
Of the total number of sperm that enter the vagina, approximately 10 million reach the uterine cavity.
Sperm lingering in the vagina die after 2 hours.
Sperm penetrate the uterus within a few hours, and the fastest ones within 1 hour. Here the environment is much friendlier for surviving gametes.
A few days before ovulation, mucous secretions appear in the female body, produced by the glands of the cervix, which are beneficial for sperm (cervical mucus). In this mucus, male reproductive cells do not lose their functionality for several days, and in other periods they die after a few hours in an unfavorable acidic environment. Because of this feature, the method of douching with a solution of lemon juice is popular in folk methods of preventing pregnancy.
In the uterus, sperm live and are suitable for fertilization for about 3-7 days.
With vaginal dysbiosis or the presence of sexually transmitted diseases in women, the acidic environment increases, which reduces the likelihood of pregnancy. However, it remains, so for those who are not planning a pregnancy, the use of contraception is a must.
From the uterus, sperm travel to the fallopian tubes, where fertilization should occur.
The strongest and most nimble 3-4 thousand male cells will remain to try to fertilize the egg. And only one can achieve the goal.
Considering the fact that sperm live in a woman’s genitals for up to 7 days, it is not always correct to count the day of conception from the day of sexual intercourse.
There is a point of view that in some cases, sperm survive during menstruation, provided they enter the fallopian tubes before menstruation. After the end of bleeding, they may still have the opportunity to fertilize the egg. This is important for women who ovulate early.
Life time in the urethra
After ejaculation, a certain part of the sperm remains in the urethra and on the foreskin of the penis. If after ejaculation there was no urination and no hygiene procedures were carried out with the genital organ, sperm can live there from 10 minutes to 2 hours. And already at the beginning of repeated sexual intercourse, these sperm drop into the female organs and begin moving towards their goal. Therefore, after the second unprotected sexual intercourse, there is a high probability of pregnancy, even if it ended in termination.
Life expectancy in the external environment
The lifespan of gametes in the open air is 2-3 hours. Therefore, during this time there is a possibility of fertilization after sperm enters the female genital organs from other parts of the body, napkins, and underwear.
After the sperm fluid evaporates, the sperm dry out and die.
When sperm is exposed to direct sunlight, in bright light, at temperatures above 38 C, in an acidic environment, sperm die almost instantly or can last a maximum of 15-20 minutes.
Life of sperm in a condom
The life time in a condom is approximately equal to the life time of male gametes in the open air - from several minutes to 3 hours. If condoms with spermicidal lubricant are used, sperm die almost immediately.
Interesting video about egg fertilization:
To increase the life of sperm and successful conception, both sexual partners need to lead a healthy lifestyle, and to prevent unwanted pregnancy, you need to use contraception and maintain genital hygiene.
In the seminal fluid, sperm move independently. But it has not been fully studied how they behave when they enter the female reproductive tract. Are they constantly moving or do they stop moving? do they receive the necessary substances from the environment in which they live, etc. But it is a known fact that sperm stored in an incubator, which is protected from drying out at body temperature, have a lifespan of more than 8 days.
Sperm maturation time
In the male body, sperm mature in 72 to 74 days. But they live quietly in appendages, hardly move and breathe little. They protect themselves until they enter the female body. If they remain in the male body for a long time, they age and become unsuitable for fertilization.
Lifespan of sperm
The lifespan of sperm in the female body is determined differently by researchers. Some believe that their life is 1-1.5 days, others 8-14 days.
Sperm movement speed
Under a microscope, the movement speed is approximately 3 mm per minute. We can say that it moves the length of its size in a second. Due to the fact that the sperm overcomes obstacles and moves against the current, a large amount of energy is consumed. And since the ciliated cilia of the fallopian tubes set the direction of this flow, the sperm always move towards the ovary. In the uterus, sperm travel 1-1.5 cm in three minutes. A few hours after intercourse, they enter the side of the fallopian tube, and there they connect with the egg. But only one sperm penetrates the egg and fertilizes it.
How long does it take for fertilization to occur?
If the calculations are correct, fertilization occurs no earlier than 8 hours later. But after what time can fertilization not occur if there has been no repeated intimacy? According to research results, fertilization can occur even 10 days after intimacy. Even in some cases, it happens, although very rarely, that if an intimate relationship took place before menstruation, sperm can survive and fertilize an egg even after the menstrual period.
What happens to sperm that has not fertilized an egg?
I wonder what happens to sperm that do not get into the egg, because only one sperm can get into it? Between 200 and 500 million sperm enter the vagina during each sexual intercourse. A small part of them, along with sperm, flows out of the vagina. The remaining part of the sperm in the vagina quickly dies under the influence of the acidity of the vaginal discharge. The fact is that the life of sperm can only exist under moderate acidity, and this acidity occurs in the vagina only at certain moments, also in a slightly alkaline environment of sperm, tubal fluid, and uterine mucus.
As a rule, dead sperm in the female body decompose, and their remains are removed by flowing out or washing. But some of their breakdown products are absorbed into the body by the vaginal wall.
A small part of the sperm still enters the uterus, but the majority die en route. Due to the fact that the uterine mucosa is more susceptible to sperm breakdown substances than the vaginal walls, some sperm directly penetrate this membrane. They were found there at all stages of decay and it is clear that in this state they are absorbed even better, replenishing the body’s juices.
A very small number of sperm ultimately survive to reach the fallopian tubes. And it is there that they all, except one, connecting with the egg, die. A certain number of sperm, which are able to resist the environment longer and have greater mobility, reach the abdominal cavity. But according to the results of experiments with the introduction of sperm into the abdominal cavity, sperm there are destroyed by phagocytes (white blood cells) and disappear in approximately less than a day.
What affects the lifespan of sperm?
The lifespan of sperm is an individual indicator that is influenced by various factors. For example, if sperm is enriched with fructose, then their lifespan will be longer. Fructose is a source of energy for sperm. Their life expectancy can be reduced by alcohol intake, medications, inflammatory diseases, etc.
To get pregnant and become a mother, you should try to be in good physical shape. A few months before conception, you should quit smoking, not abuse alcohol, and try to take less medications. You should also avoid harmful or stressful work. If you or someone in your family suffers from any congenital disease, consult your doctor to see if this will threaten your pregnancy.
During ovulation, your body temperature rises slightly. If you measure your temperature for at least three months, you will notice a pattern: it starts out at about 36.6 C, then rises during ovulation. Three months before conceiving, stop taking medications and get a rubella measles vaccine. Your last menstrual period has just begun and you can already plan your pregnancy. Preconceptional pregnancy planning is a very good idea. However, if you have not started testing before your planned pregnancy, at least take a prenatal vitamin and 4 mg of folic acid per day to help prevent neural tube defects.
Health and pregnancy
Your health will play a primary role in the next 40 weeks of pregnancy. Your health will determine how easy your pregnancy will be and how healthy your baby will be born. A healthy diet, regular exercise (but only with the permission of your doctor!) and frequent, long rest will allow you to live these 9 wonderful months of pregnancy with pleasure and a smile and show the world a beautiful, happy child.
If you smoke and are trying to get pregnant, it's time to quit this bad habit. Both you and your baby will benefit from this. But there is worse news - you will have to give up alcohol and reduce the amount of caffeine you consume. Don't be upset, just imagine the smile of your future belly... you can do even more for the sake of this smile!
Questions about which position is best for conceiving a child
1) Are there any positions that are preferable for conception?
There is no reason to believe that any sex position is better for conception. You may have heard that fertilization is more likely in a position where the sperm gets closer to the cervix (missionary, for example), but there is no clear research or evidence for this theory.
At the same time, choosing the “right” time plays a critical role. To increase the chance of conception, it is better to have sex two days before expected ovulation and again on the day of ovulation.
2) Does orgasm increase the chances of conception?
There is an opinion that a woman experiencing an orgasm after her partner ejaculates increases her chances of becoming pregnant, but there is no scientifically proven basis for this statement.
Female orgasm is not at all a necessary component for conception, but the muscular contractions of the vagina that occur at this moment may well help sperm reach the fallopian tubes (such painless, imperceptible contractions occur without sex, especially on the days of ovulation).
3) Should you lie down after intercourse to increase the likelihood of conception?
Staying horizontal for an extra 15 minutes after sex allows more sperm to linger in your vagina. But at the same time, in each ejaculation there are millions of sperm, so even if you jump up right away, there will still be more than one million sperm left in the vagina.
If you and your partner have been trying to conceive for more than a year (or more than 6 months if you are over 35) without success, or your cycle is not regular, you should consult a specialist.
Planning the gender of the child
The sex of the child depends on which sperm fertilized the egg. Fertilization of an egg with a sperm with the X chromosome will lead to the development of a female embryo, while a sperm with the Y chromosome will lead to the conception of a boy. There is a theory that sperm with different chromosomes have different characteristics, knowledge of which can help create the most favorable conditions for conceiving a child of a certain sex.
Estimated sperm characteristics:
Sperm with the Y chromosome, leading to the birth of a boy, move faster and live shorter than sperm with the X chromosome. The latter, leading to the birth of a girl, are less mobile, but can survive longer in the woman’s body, waiting for ovulation.
Knowing these features, you can try to plan the gender of the child if you follow the following rules:
To conceive a boy
The time of sexual intercourse should be as close as possible to the date of ovulation. If we assume that Y sperm move faster than their counterparts, then the likelihood that they will be the first to reach and fertilize the egg is higher. Avoid sexual intercourse 4 or 5 days before ovulation. Penetration during sexual intercourse should be “deep”, which will bring short-lived Y sperm as close as possible to the entrance to the uterus, and therefore shorten their path to the egg. Men should avoid overheating. Increased temperature caused by a sauna or very warm clothing leads to a general decrease in sperm count, but overheating is thought to be particularly detrimental to Y sperm. It is better if during sexual intercourse a woman experiences orgasm before her partner, or at least at the same time. During orgasm, a certain secretion is released into the vagina, which promotes the survival of Y sperm.
To conceive a girl
Plan to have sexual intercourse 2-3 days before ovulation and avoid sexual intercourse during ovulation and up to 2 days after it. X sperm, according to their characteristics, have a much higher chance of surviving 2 days while waiting for an egg than their counterparts.
Penetration during sexual intercourse should be “shallow.” This will lengthen the path to the egg and give the slower, but longer-living X sperm a chance to reach the egg after a few days and reduce the chances of their fellow sperm. It's better if the woman doesn't have an orgasm. X sperm can survive longer in the alkaline environment of the vagina and, unlike their counterparts, do not suffer from the lack of secretions released during orgasm. This method is not recommended if you have problems conceiving or have been diagnosed with infertility, as it can significantly increase the period of planning a child.
Time of conception
So, you have finally answered the question: “Do I want to become a mother?” Yes, I want! Great. To do this, you need to choose the right moment to conceive. We are ready to help you with this.
Sperm enter the uterus during sexual intercourse. Then, with the help of their tails, they begin to move towards the fallopian tubes. If at that time ovulation has already occurred in the female body, then here they meet a mature egg.
Male reproductive cells are able to remain active for two days. If the egg does not ovulate during this period, then conception will not occur and they will die. Therefore, it is clear that the most favorable time for fertilization is the period of ovulation with slight deviations in one direction or the other.
Since the lifespan of an egg is 24 hours, the days before ovulation are more preferable for conception than after it, since sperm require more than a day to enter the fallopian tube. Determining the date of ovulation and calculating favorable days for pregnancy is best done using the temperature curve, and you can also consult a gynecologist in the middle of the menstrual cycle, who, using a simple analysis of mucus taken from the cervix, will determine the date of ovulation with an accuracy of 1 -2 days.
For conception, it is better if a woman lies on her back during intercourse. After it is finished, you can put a pillow under your buttocks and raise your legs. This position must be maintained for some time. In this case, the cervix will be immersed in the sperm located in the posterior fornix of the vagina.
The knee-elbow position during or after sexual intercourse also helps facilitate the penetration of sperm into the cervical canal.
Most young women who are recently sexually active do not experience orgasm during intercourse. Orgasm is not necessary for pregnancy to occur.
In the days preceding conception, spouses should completely avoid drinking alcohol, since alcohol has a damaging effect on both female and male reproductive cells.
Be careful with other harmful factors - varnishes, paints, solvents, various household chemicals, do not do x-rays, this also applies to taking medications.
If you are not entirely healthy, it is better to postpone pregnancy until recovery. If you take any medication for a long time you need to consult your doctor about its possible effect on conception and pregnancy.
Without sufficient medical grounds, you should not resort to an ultrasound diagnostic procedure, although its adverse effect on the body is minimal.
How to get pregnant quickly? How to calculate the day of ovulation?
Today, the average age of women wanting to get pregnant is close to 30 years. Add to this work, a busy lifestyle, stress, smoking, and the environment. It is safe to say that today conceiving a child is hard work.There are diseases that can cause irreparable harm to the fetus. Therefore, before conceiving, do not forget to undergo an examination with your future dad to make sure that you are healthy. And if health problems are identified, undergo a course of treatment.
To increase your chances of conceiving and getting pregnant quickly, a woman needs to know when she ovulates. There are many ways to calculate the day of ovulation, but for greatest accuracy it is better to use several at once:
Calendar method: theoretically, ovulation occurs 12-16 (usually 14) days before the end of the cycle. By keeping a menstruation calendar, you can calculate days favorable for conception. To do this, we subtract 16 from the shortest cycle, and subtract 12 from the longest cycle, and respectively get the most probable days of ovulation. With a regular cycle, this is an interval of 5 days, and if the cycle is irregular, then the interval increases even more.
Basal temperature: every morning, without getting out of bed and without making sudden movements, the temperature in the rectum or vagina is measured. A graph of temperatures per cycle is drawn up. If you are healthy, then in the first half of the cycle the temperature does not change, then it sharply decreases by 0.4-0.6 degrees, after which it rises and does not change throughout the second half of the cycle. The time of ovulation is precisely the time when the temperature drops by 0.4-0.6 degrees.
According to the nature of the discharge: 3-5 days before ovulation, the discharge becomes abundant, transparent, and resembles the consistency of egg white. The largest number of such discharges is observed on the day of ovulation. After ovulation, the discharge becomes light, thick and creamy.
Saliva examination: During ovulation, the amount of estrogen increases, which in turn changes the composition of saliva, forming crystalline structures that under the microscope resemble a fern. Nowadays special microscopes are produced, the size of lipstick. This microscope can easily fit into your purse.
Ovulation test: sold in any pharmacy, easy to use, contains instructions. Ovulation occurs within 24 hours after receiving the first positive result.
Ultrasound monitoring: carried out in specialized clinics using the vaginal sensor of an ultrasound machine. On days 7-10 of the cycle, the doctor examines the ovaries and determines whether ovulation will occur in this cycle. Then every 2-3 days he monitors the growth of follicles, until the day of ovulation.
If your first attempts to conceive a baby are unsuccessful, this is not yet a reason to sound the alarm. Just be patient and keep working. Only after a year of unsuccessful attempts does it make sense to seek help from medicine.
How long can sperm live in a woman’s body and retain fertilizing ability? What happens to sperm that do not reach the egg?
Sperm move independently in seminal fluid. However, it is not known how they behave once they enter the female genital tract: whether they constantly move or sometimes stop moving; whether the substances necessary to restore the energy spent on movement are obtained from the products of the environment in which they live, or together with the seminal fluid. But since we know that sperm stored in an incubator at body temperature and protected from drying out remain alive for more than 8 days and are in constant motion during this period, we can assume that they maintain their mobility throughout the entire time they are present in the female genital tract .
The lifespan of sperm in the body is determined by researchers in different ways. Some authors believe that it is 24-36 hours, others - 8-14 days.
Under a microscope, the speed of movement of a sperm is approximately 3 mm per minute, i.e., in a second it moves the length of its body. When moving, a lot of energy is consumed, since the sperm is forced to overcome
obstacles and move against the flow. And since the ciliated cilia of the female fallopian tubes set the direction of this flow, sperm always move towards the ovary. The capillary nature of this flow naturally reduces their speed. It is believed that in the uterus, sperm travel 1-1.5 cm in 3 minutes, i.e., to leave the seminal mass, enter the uterine pharynx and from there rise into the uterine cavity, the sperm needs approximately 1.5-3 hours. A few hours later, they can be found at the side of the fallopian tube, where they connect to the egg. Only one sperm penetrates the egg, its head fuses with the nucleus, and this fusion, in essence, is fertilization.
If these calculations are considered correct, then fertilization occurs no earlier than 8 hours after sexual intercourse. The question arises: after what period of time can fertilization not occur, unless, of course, there was repeated copulation? The answer is not easy. But the results of observations give reason to believe that this period can be very long. It is possible that a sperm can fertilize an egg even 8-10 days after copulation. Some researchers believe that if sexual intercourse took place before menstruation, sperm can survive in the tube and fertilize the egg after the menstrual period. This hypothesis cannot be rejected unconditionally, especially when it comes to early ovulation. It is currently accepted that sperm can remain motile in the cervical mucus or tube for 7-8 days, but their fertilizing ability remains approximately 24 hours.
What happens to sperm that do not reach the egg? After all, the egg can only accept one sperm and after that it is closed to everyone else. And since with each copulation 200-500 million sperm enter the vagina, it is clear that a countless number of them die. Some sperm leave the vagina along with the sperm that flows out of it. The remaining, also significant, part quickly dies in the vagina under the influence of the high acidity of vaginal discharge. Spermatozoa can live only in moderate acidity, which occurs in the vagina at certain times, as well as in the weak alkaline environment of sperm, uterine mucus, and tubal fluid.
Dead spermatozoa decompose. Their remains flow out of the vagina or are removed by rinsing. On the other hand, their breakdown products, as well as other substances contained in sperm, are absorbed by the vaginal wall and enter the body.
A small part of the sperm enters the uterus and moves towards the tubes, but most of them die along the way. Since the susceptibility of the uterine mucosa to sperm breakdown products is greater than that of the vaginal walls, some sperm penetrate directly into this lining. They were found there between the cells at all stages of decay, and it is clear that in this state they are absorbed even better and replenish the body's juices.
Ultimately, very few sperm make it to the fallopian tubes. And there they all, except one, who fertilizes the egg, die. However, no one noted their presence in the mucous membrane of the tubes. Probably, the remains of dead sperm are carried by capillary flow into the uterus.
Some sperm, which are able to resist longer and have the greatest mobility, sometimes reach the abdominal cavity.
As experiments with the introduction of sperm into the abdominal cavity have shown, there the sperm are devoured by phagocytes (white blood cells), which provide protection to the body, are digested and disappear within approximately twenty hours.
Fertilization is a sacrament in which the female and male reproductive cells participate. But how soon does it come? How long will it take the sperm to reach its goal? The answers to these questions are ambiguous and depend on many factors. To find out exactly when the sperm reaches the egg, it is necessary to understand the processes occurring in the female body.
Ovulation occurs approximately on days 14-15 of the monthly cycle. At this time, a mature female reproductive cell emerges from the follicle located in the ovary; it is already completely ready for fertilization. Next comes the picking up of the egg by the villi lining the fallopian tubes; during their contraction, the female reproductive cell gradually moves towards the uterus. The woman’s body is waiting for fertilization, which is possible only for 24 hours; such a short period of ovulation is explained by the viability of the egg. The sperm reaches the egg only after successfully overcoming a number of obstacles. Half a billion sperm are actively moving towards the egg, but only one of them will reach the goal.
The distance that the sperm must travel to the egg is only 20 cm. The time spent on this journey will be several hours. Not all sperm successfully overcome obstacles along the way; a huge number of them die. Some sperm with structural defects will not be able to travel even a few centimeters; they will die. That part of the sperm that has greater mobility goes to the goal. How many male reproductive cells reach the uterus? About 10 million sperm penetrate the uterine cavity; during movement, they can involuntarily help each other. Only 3-4 thousand sperm will reach the finish line. Many active spermatozoa will “drill” the mucous membrane, but often one of them can penetrate inside.
If two sperm penetrate inside a female reproductive cell, although this happens quite rarely, the birth of two lives occurs - fraternal twins.
The time it takes a sperm to travel to the fallopian tubes for fertilization can last several hours, but it can reach the egg in 3-4 days. How long does it take for sperm to meet an egg? Sexual intercourse does not always occur on the day of ovulation; fertilization can also occur when seminal fluid penetrates the vagina 5 days before the “hour X” or 2 days after its onset.
Sperm can wait to meet the female reproductive cell not only in the fallopian tubes, but also in the uterus, as well as the cervix itself. So how do sperm “understand” that they need to move on? It’s very simple, the egg “attracts” sperm to itself with special chemicals, forcing them to move forward again.
During the complete penetration of the sperm into the egg, all the processes that previously took place here change. The outer shells soften, which promotes the rapid accumulation of nutrients, the absorption of potassium and phosphorus begins, and the production of proteins, carbohydrates, and calcium increases. The first 12 hours after conception are of great importance for the future fetus.
The path of a sperm to its goal is complex, full of difficulties and obstacles. Immediately after the male reproductive cells enter the vagina with seminal fluid, they cannot fully move. It's all due to the presence of female secretions in the vagina. Only after sperm have passed through the mucus are they capable of fertilization. The acidic environment has a detrimental effect on sperm; not all male cells survive. Female sperm (with an X chromosome) are more tenacious and survive well even in the acidic flora of the vagina than cells carrying a Y chromosome. The grooves at the very beginning of the journey retain some of the sperm, preventing them from moving forward. Even after passing through the uterine cavity, not everyone ends up in the desired fallopian tube and dies, so to speak, at the finish line.
In the presence of certain factors, the movement of sperm in the internal genital organs occurs faster. If a woman feels an orgasm during intercourse, vaginal contractions help propel sperm to the cervix. But having an orgasm is not a prerequisite for fertilization. During the period of ovulation, vaginal mucus is more liquid, and the cervix is maximally dilated, which reduces the time to reach the female reproductive cell.
The fallopian tubes also “help” sperm in achieving their goal; they secrete a special alkaline secretion that nourishes the male reproductive cells that are waiting to meet the egg. This supports the vital activity of sperm and their motor activity.
How long will it take from intercourse to fertilization? The coincidence of the period of ovulation and sexual contact plays a big role in this. The sperm lives in the female body for no more than four days. Sometimes they do not live only a few hours before the egg is released. Successful fertilization is possible if sexual intercourse occurs 2 or 3 days before ovulation. If sperm enters the fallopian tube after ovulation, there is no chance of fertilization. Pregnancy does not occur in this cycle; the egg and sperm die.
