Sperm Wars Scene 7 A Sperm War
SCENE 7
A Sperm War
From the book Sperm Wars, by Robin Baker
As the woman and her lover sink to the floor, only moments away from intercourse, her body already contains sperm. Her partner inseminated a total of six hundred million during their routine intercourses the previous weekend. Most were ejected in her various flowbacks, but even so some are still inside her. Their ability to influence the outcome of sperm warfare, however, depends on where they are.
A few ineffectual sperm are at the top of her vagina, carried there by cervical mucus, which has been dripping out of her cervix and oozing down her vagina all day in anticipation of this moment of infidelity. Each drip of mucus carried with it a few of her partner's sperm. As these sperm were lost from the future battleground in her cervix, they were partly replaced higher up by the last handfuls of sperm from her cervical crypts. These emerged and entered her mucus channels in a vain attempt to make good the numbers being lost into her vagina. However, the numbers being lost were greater than the number of their replacements, and all day her partner's cervical defences had been slowly declining.
The sperm lodged in her cervical mucus are not the sleek types already referred to. Instead, they are sluggardly blockers sperm whose role is to prevent any later sperm from passing through to her cervical crypts and womb. Sperm with coiled tails, a bent mid-piece, a large 'rucksack', a large head, or with two, three or four heads can block very effectively any of the very narrow mucus channels in which they lodge. So, too, can two sperm side by side. As her lover thrusts inside her, however, relatively few of her mucus channels are still blocked by this rapidly dwindling collection of her partner's sperm.
These blocking sperm are not her partner's only defence inside her body. Roaming around in the void of her womb are a few more of his sperm, though these too are dwindling in numbers. These sperm look familiar. They are svelte and athletic, but they are not there to fertilise. These are killer sperm, roaming around in search of sperm from other men to destroy. Each time a killer encounters another sperm, it tests the chemicals on the surface of the other's head. If those chemicals are the same as on its own head, the killer recognises an ally and moves on to continue its search. So far, all encounters inside this woman have been with allies and the killers' deadly services have not been needed. Many are now beginning to move slowly, and large numbers are dying of old age. The weakest have been in her womb for three days. The more active are more recent arrivals from the reservoirs in her cervical crypts.
The woman's womb is not the only territory ******d by killers. A few more are s**ttered along her oviducts. There is even one swimming solitarily in her body cavity near to her left ovary. These killer sperm in her oviducts accompany the last handful of the partner's fertile sperm, the egg-getters. Killer sperm and egg- getters look very similar. They are both sleek and athletic in form but, whereas the killers have average-sized heads, the heads of the egg-getters are slightly larger. If the woman ovulated now, her partner would still have a good chance of fertilisation. But ovulation is still two days away, and war is about to begin.
After very few thrusts, the lover deposits his seminal pool in the woman's vagina. Her cervix dips into and stays in the pool, and the vanguard of his army begins to stream into the channels of her cervical mucus. This army contains about five hundred million killer sperm, about one million egg-getters, and about a hundred million blockers. Some are denied passage through mucus channels by the partner's blocking sperm. So few of these blockers remain, though, that almost all of the cervical channels are now clear. The invaders pour through in waves. A few hundred egg- getters with support from killers travel straight through the cervix into the womb, heading immediately for the rest area in the oviduct. The remainder of the egg-getters, some of me killers and the youngest of the blockers — a few million in all — head for the cervical crypts. They pour in, settle down, and await developments. The remainder of the killers travel more slowly through the cervix into the womb, leaving behind the much slower blockers. These latter distribute themselves throughout the mucus channels, then settle down, many immediately coiling their tails as if in anticipation of a long wait.
Some of the vanguard of the lover's egg-getters do not make it to the oviduct. As we have seen, the partner has relatively few killer sperm still active in the womb, but those that are there do their best to stem the lover's tide. As soon as a killer from either man first encounters a sperm from the rival, it is alerted that war has begun. For an hour or so, the killers from both men swim much faster than normally, seeking out as many rival sperm as possible. Their aim is to poison the rival's egg-getters and killers using the deadly cocktail of fluids in the cap which they each carry on their heads. They do this via head-to-head combat. First, as we have seen, they probe with the tips of their heads at every sperm they encounter, comparing its surface chemicals with their own and checking for similarities and differences. If a killer finds a sperm from the rival's army, it tries to jab the deadly tip of its head against the vulnerable side of its opponent's head, applying a small amount of corrosive poison with each jab. Having jabbed several times it moves on, leaving the other sperm to die.
A single killer sperm carries enough poison to kill many sperm from the rival army, but gradually its cap runs out of chemicals, for it has no reserves of energy to make any more. In a last-ditch attempt to kill just one more sperm, it tries to stick its head to a rival's and apply the last drops of its lethal fluids. As the war progresses, there is a gradual increase in these pairs of dead and dying sperm, joined at the head in a deadly embrace.
In this initial skirmish, one or two of the partner's killers do their job and some of the lover's egg-getters and killers die from head-to-head combat, their heads coated in the poison. Any initial success of the partner's sperm, though, is short-lived. In their turn, they are found by the invading bands of killers from the lover which accompany his egg-getters. In a frenzy of kamikaze mayhem, killer sperm from both sides attempt In annihilate each other's troops. Outnumbered by at least a thousand to one, however, the last remaining sperm from the partner are soon killed.
The battlefront now moves into the oviducts, where the killing continues. With only a few losses of their own, the lover's sperm systematically wipe out the partner's last remaining egg-getters and killers. By the time the woman and her lover have sex again, an hour later, the first battle is over and none of the partner's sperm remain alive inside her. Actually, the role of the second insemination in this particular sperm war is more complicated than it seems — but here that discussion would be a distraction.
So far, our war has been so one-sided that it has been little more than a brushing aside. The main battle is still to come. It begins when the woman gets home and her body urges her to sit astride her partner, push his penis into her vagina, and stimulate him to ejaculate. By doing so, she has staged a real war. Nevertheless, even though her partner now enters a fresh army of three hundred million sperm into the arena, the contest is still going to be one-sided.
As soon as the newly introduced sperm from the partner attempt to leave the seminal pool, they encounter problems. The channels of the woman's cervical mucus are nearly all blocked, not only with sperm from the lover, but also with white blood cells from the woman herself. The huge number of the lover's sperm and the matching number of white blood cells are doing their job almost perfectly, and the partner's sperm are much more hindered in leaving the seminal pool than were the lover's, a couple of hours earlier. Queues of the partner's sperm develop in the blocked channels, producing tailbacks all the way to the seminal pool. As a result, only a small proportion of the partner's army manages to escape the pool before the woman ejects her flowback.
Even those sperm which do escape the pool and find a clear channel are not yet out of trouble. The small vanguard of egg-getters and killers which head straight into the womb find themselves having to run the gauntlet of hordes of the lover's killers. Inevitably, one or two get through without being poisoned, but only to run into further problems as they then try to leave the womb. The entrance into each oviduct is narrow, only just large enough to allow easy passage to a descending egg. Moreover, both oviduct entrances are blocked by lover's sperm and patrolled by killers, and many of the partner's sperm are killed as they try to push through. Even those few that do escape and eventually arrive safely in the oviduct rest area are still at risk to the lover's killers, which patrol the whole area.
Lower down in the woman's tract, in her cervix, many of her partner's sperm are trying to enter her cervical crypts. But the crypt entrances too are patrolled by killers and, in any case, inside they are virtually full of the lover's sperm. Just occasionally, some of the partner's sperm stumble across a channel leading to an empty crypt, but the majority get stranded in the mucus where they fall prey to the combined forces of the lover's sperm and the woman's white blood cells.
Clearly, the Wednesday encounter in this war has gone very much in favour of the lover, and nothing much happens over be next two days to redress the balance. As the woman goes about as normal on Thursday and Friday, the population of blocking sperm from both men in her cervical mucus slowly declines. Some drip into her vagina, carried by mucus. Others are mopped up by rearguard white blood cells. Even when some of these blockers are replaced higher up in her cervix with sperm from the cervical crypts, the new recruits fail to make good the loss and the blockers dwindle. The killer sperm in her womb, after an initial decline from battle losses, actually build up in numbers on Thursday with a fresh recruitment from the cervical crypts. Then the killers also begin to decline in number. A steady flow of egg-getters from both men (but mainly the lover) leave the crypts, heading for the rest areas in the oviducts. En route, they have to run the gauntlet of rival killer sperm in the womb, and most of the partner's egg- getters fail because these killers are almost all from the lover. By Friday night, with only hours now to go to ovulation, the partner's egg-getters in the oviducts are outnumbered by about one hundred to one.
When the woman and her partner have sex on the Friday night, there is only one more hour to ovulation. Now, the partner's sperm have a much easier passage through the cervical mucus because the number of blockers is much reduced. Although most of his sperm head for the now half-empty cervical crypts, a vanguard of egg-getters and killers head straight for the oviducts. Many are killed or slowed down in the womb by the lover's patrolling killers, but enough get through to reduce the odds in the oviducts from a hundred to one to about ten to one. It is at this point that the woman produces an egg from one of her ovaries and a chemical signal passes down the adjacent oviduct. This signal activates hundreds of the sperm in the rest area, and a wave of sperm begin to make their way up the oviduct towards the fertilisation zone. It is now a race, or rather an obstacle race because there are still killers in the oviduct, mainly from the lover. The partner's sperm, particularly those few which have just arrived straight from the insemination, are actually fastball than the lover's - if all else were equal, the partner could still win the prize of fertilisation.
But all else is not equal. One after another, the partner's egg-getters run into the lover's killer sperm. As the egg reaches the zone of fertilisation in the oviduct and the first sperm arrive, the odds against the partner have reduced to five to one, but that is not enough. The first three sperm to arrive are all from the lover, and one of these claims the prize. An hour later, with the partner's fresh sperm now overwhelming the lover's at all points in the woman's tract, the odds in the oviducts swing heavily in the partner's favour. But it is too late. The lover has made it and the woman's daughter, to be born in nine months' time, will not have been sired by the man she will call her father. But nobody will ever know.
A Sperm War
From the book Sperm Wars, by Robin Baker
As the woman and her lover sink to the floor, only moments away from intercourse, her body already contains sperm. Her partner inseminated a total of six hundred million during their routine intercourses the previous weekend. Most were ejected in her various flowbacks, but even so some are still inside her. Their ability to influence the outcome of sperm warfare, however, depends on where they are.
A few ineffectual sperm are at the top of her vagina, carried there by cervical mucus, which has been dripping out of her cervix and oozing down her vagina all day in anticipation of this moment of infidelity. Each drip of mucus carried with it a few of her partner's sperm. As these sperm were lost from the future battleground in her cervix, they were partly replaced higher up by the last handfuls of sperm from her cervical crypts. These emerged and entered her mucus channels in a vain attempt to make good the numbers being lost into her vagina. However, the numbers being lost were greater than the number of their replacements, and all day her partner's cervical defences had been slowly declining.
The sperm lodged in her cervical mucus are not the sleek types already referred to. Instead, they are sluggardly blockers sperm whose role is to prevent any later sperm from passing through to her cervical crypts and womb. Sperm with coiled tails, a bent mid-piece, a large 'rucksack', a large head, or with two, three or four heads can block very effectively any of the very narrow mucus channels in which they lodge. So, too, can two sperm side by side. As her lover thrusts inside her, however, relatively few of her mucus channels are still blocked by this rapidly dwindling collection of her partner's sperm.
These blocking sperm are not her partner's only defence inside her body. Roaming around in the void of her womb are a few more of his sperm, though these too are dwindling in numbers. These sperm look familiar. They are svelte and athletic, but they are not there to fertilise. These are killer sperm, roaming around in search of sperm from other men to destroy. Each time a killer encounters another sperm, it tests the chemicals on the surface of the other's head. If those chemicals are the same as on its own head, the killer recognises an ally and moves on to continue its search. So far, all encounters inside this woman have been with allies and the killers' deadly services have not been needed. Many are now beginning to move slowly, and large numbers are dying of old age. The weakest have been in her womb for three days. The more active are more recent arrivals from the reservoirs in her cervical crypts.
The woman's womb is not the only territory ******d by killers. A few more are s**ttered along her oviducts. There is even one swimming solitarily in her body cavity near to her left ovary. These killer sperm in her oviducts accompany the last handful of the partner's fertile sperm, the egg-getters. Killer sperm and egg- getters look very similar. They are both sleek and athletic in form but, whereas the killers have average-sized heads, the heads of the egg-getters are slightly larger. If the woman ovulated now, her partner would still have a good chance of fertilisation. But ovulation is still two days away, and war is about to begin.
After very few thrusts, the lover deposits his seminal pool in the woman's vagina. Her cervix dips into and stays in the pool, and the vanguard of his army begins to stream into the channels of her cervical mucus. This army contains about five hundred million killer sperm, about one million egg-getters, and about a hundred million blockers. Some are denied passage through mucus channels by the partner's blocking sperm. So few of these blockers remain, though, that almost all of the cervical channels are now clear. The invaders pour through in waves. A few hundred egg- getters with support from killers travel straight through the cervix into the womb, heading immediately for the rest area in the oviduct. The remainder of the egg-getters, some of me killers and the youngest of the blockers — a few million in all — head for the cervical crypts. They pour in, settle down, and await developments. The remainder of the killers travel more slowly through the cervix into the womb, leaving behind the much slower blockers. These latter distribute themselves throughout the mucus channels, then settle down, many immediately coiling their tails as if in anticipation of a long wait.
Some of the vanguard of the lover's egg-getters do not make it to the oviduct. As we have seen, the partner has relatively few killer sperm still active in the womb, but those that are there do their best to stem the lover's tide. As soon as a killer from either man first encounters a sperm from the rival, it is alerted that war has begun. For an hour or so, the killers from both men swim much faster than normally, seeking out as many rival sperm as possible. Their aim is to poison the rival's egg-getters and killers using the deadly cocktail of fluids in the cap which they each carry on their heads. They do this via head-to-head combat. First, as we have seen, they probe with the tips of their heads at every sperm they encounter, comparing its surface chemicals with their own and checking for similarities and differences. If a killer finds a sperm from the rival's army, it tries to jab the deadly tip of its head against the vulnerable side of its opponent's head, applying a small amount of corrosive poison with each jab. Having jabbed several times it moves on, leaving the other sperm to die.
A single killer sperm carries enough poison to kill many sperm from the rival army, but gradually its cap runs out of chemicals, for it has no reserves of energy to make any more. In a last-ditch attempt to kill just one more sperm, it tries to stick its head to a rival's and apply the last drops of its lethal fluids. As the war progresses, there is a gradual increase in these pairs of dead and dying sperm, joined at the head in a deadly embrace.
In this initial skirmish, one or two of the partner's killers do their job and some of the lover's egg-getters and killers die from head-to-head combat, their heads coated in the poison. Any initial success of the partner's sperm, though, is short-lived. In their turn, they are found by the invading bands of killers from the lover which accompany his egg-getters. In a frenzy of kamikaze mayhem, killer sperm from both sides attempt In annihilate each other's troops. Outnumbered by at least a thousand to one, however, the last remaining sperm from the partner are soon killed.
The battlefront now moves into the oviducts, where the killing continues. With only a few losses of their own, the lover's sperm systematically wipe out the partner's last remaining egg-getters and killers. By the time the woman and her lover have sex again, an hour later, the first battle is over and none of the partner's sperm remain alive inside her. Actually, the role of the second insemination in this particular sperm war is more complicated than it seems — but here that discussion would be a distraction.
So far, our war has been so one-sided that it has been little more than a brushing aside. The main battle is still to come. It begins when the woman gets home and her body urges her to sit astride her partner, push his penis into her vagina, and stimulate him to ejaculate. By doing so, she has staged a real war. Nevertheless, even though her partner now enters a fresh army of three hundred million sperm into the arena, the contest is still going to be one-sided.
As soon as the newly introduced sperm from the partner attempt to leave the seminal pool, they encounter problems. The channels of the woman's cervical mucus are nearly all blocked, not only with sperm from the lover, but also with white blood cells from the woman herself. The huge number of the lover's sperm and the matching number of white blood cells are doing their job almost perfectly, and the partner's sperm are much more hindered in leaving the seminal pool than were the lover's, a couple of hours earlier. Queues of the partner's sperm develop in the blocked channels, producing tailbacks all the way to the seminal pool. As a result, only a small proportion of the partner's army manages to escape the pool before the woman ejects her flowback.
Even those sperm which do escape the pool and find a clear channel are not yet out of trouble. The small vanguard of egg-getters and killers which head straight into the womb find themselves having to run the gauntlet of hordes of the lover's killers. Inevitably, one or two get through without being poisoned, but only to run into further problems as they then try to leave the womb. The entrance into each oviduct is narrow, only just large enough to allow easy passage to a descending egg. Moreover, both oviduct entrances are blocked by lover's sperm and patrolled by killers, and many of the partner's sperm are killed as they try to push through. Even those few that do escape and eventually arrive safely in the oviduct rest area are still at risk to the lover's killers, which patrol the whole area.
Lower down in the woman's tract, in her cervix, many of her partner's sperm are trying to enter her cervical crypts. But the crypt entrances too are patrolled by killers and, in any case, inside they are virtually full of the lover's sperm. Just occasionally, some of the partner's sperm stumble across a channel leading to an empty crypt, but the majority get stranded in the mucus where they fall prey to the combined forces of the lover's sperm and the woman's white blood cells.
Clearly, the Wednesday encounter in this war has gone very much in favour of the lover, and nothing much happens over be next two days to redress the balance. As the woman goes about as normal on Thursday and Friday, the population of blocking sperm from both men in her cervical mucus slowly declines. Some drip into her vagina, carried by mucus. Others are mopped up by rearguard white blood cells. Even when some of these blockers are replaced higher up in her cervix with sperm from the cervical crypts, the new recruits fail to make good the loss and the blockers dwindle. The killer sperm in her womb, after an initial decline from battle losses, actually build up in numbers on Thursday with a fresh recruitment from the cervical crypts. Then the killers also begin to decline in number. A steady flow of egg-getters from both men (but mainly the lover) leave the crypts, heading for the rest areas in the oviducts. En route, they have to run the gauntlet of rival killer sperm in the womb, and most of the partner's egg- getters fail because these killers are almost all from the lover. By Friday night, with only hours now to go to ovulation, the partner's egg-getters in the oviducts are outnumbered by about one hundred to one.
When the woman and her partner have sex on the Friday night, there is only one more hour to ovulation. Now, the partner's sperm have a much easier passage through the cervical mucus because the number of blockers is much reduced. Although most of his sperm head for the now half-empty cervical crypts, a vanguard of egg-getters and killers head straight for the oviducts. Many are killed or slowed down in the womb by the lover's patrolling killers, but enough get through to reduce the odds in the oviducts from a hundred to one to about ten to one. It is at this point that the woman produces an egg from one of her ovaries and a chemical signal passes down the adjacent oviduct. This signal activates hundreds of the sperm in the rest area, and a wave of sperm begin to make their way up the oviduct towards the fertilisation zone. It is now a race, or rather an obstacle race because there are still killers in the oviduct, mainly from the lover. The partner's sperm, particularly those few which have just arrived straight from the insemination, are actually fastball than the lover's - if all else were equal, the partner could still win the prize of fertilisation.
But all else is not equal. One after another, the partner's egg-getters run into the lover's killer sperm. As the egg reaches the zone of fertilisation in the oviduct and the first sperm arrive, the odds against the partner have reduced to five to one, but that is not enough. The first three sperm to arrive are all from the lover, and one of these claims the prize. An hour later, with the partner's fresh sperm now overwhelming the lover's at all points in the woman's tract, the odds in the oviducts swing heavily in the partner's favour. But it is too late. The lover has made it and the woman's daughter, to be born in nine months' time, will not have been sired by the man she will call her father. But nobody will ever know.
11年前
