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  #1  
Old 11-06-2009, 05:50 AM
Sragde Sragde is offline
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What is the minimum volume of sperma required to get pregnant?

Recently I read an article in which a gynecologist stated that a ''drop of sperma is enough to get pregnant'', so ''interrupted sex'' method of contraception is like a ''Russian roulette''. She said that there is a million of spermatozoids in a drop of sperma.

As I was taught in Pharmacology, 1 mL of water contains 20 drops. I presume the same is approximately correct for sperma. So I pretty much doubt that a drop of sperma is enough to get pregnant.

Even more I doubt in that for the reason, that in a lecture my Embryology professor said that one portion of ejaculate contains, if I'm not mistaken (that was two years ago), 30 millions of spermatozoids. And one portion is far more than a drop or a mililiter. But what I remember exactly, is that she said that although only one spermatozoid (sometimes two or few) fertilizes the ovocyte, the capacity of one spermatozoid for getting through the coats and membrane of the egg is not sufficient and other spermatozoids are required for their enzymes to help dissolving the coats. Besides, as the fertilization takes place in Fallopian tube, it is quite a long way from the vagina for the spermatozoid to travel. And even like that wasn't a problem, 70 percent of spermatozoids should be active with the minimum speed of 2-3 mm per minute in the presence of cervical and vaginal secretion.

So my question is: is a drop of sperma really enough for a woman to get pregnant or does it require more?

And I also have an additional question. I heard from another gynecologist, that it is not possible to get pregnant during the first 12 days after menses. I do understand that ovulation time may vary every month, but anyway: what do you think?

Any physicians? Biologists?

Please, speak out!

Thanks in advance!
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  #2  
Old 11-06-2009, 06:33 AM
JerseyFrank JerseyFrank is offline
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Quote:
Originally Posted by Sragde View Post
So my question is: is a drop of sperma really enough for a woman to get pregnant or does it require more?
The only requirement is that a single swimmer make his way to and fertilize an egg. Unlikely, yes, but that's what's "required." I don't know the statistics on how many sperm cells it would take to ensure a given confidence level of no fertilization, but anything less than total abstention from sex introduces some chance of pregnancy.

My personal level of risk tolerance is such that I use a condom as the only method of birth control. I'm married & monogamous.
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  #3  
Old 11-06-2009, 07:56 AM
Triskadecamus Triskadecamus is offline
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The periods of viability of sperm, the exact times of ovulation, and the interactions of a host of unpredictable factors make the twelve day fertile period a very rough estimate. One sperm cell is both the minimum, and the maximum necessary to fertilize an ovum.

There is a well known technical term for people who rely on the Rhythm Method. They are referred to as parents.

Tris
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  #4  
Old 11-06-2009, 08:40 AM
pan1 pan1 is offline
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12 days is an arbitrary number and mostly wrong.

Cycles are measured from the first day of the bleed.

Ovulation varies from woman to woman but can be anywhere from a week to several weeks after the cycle starts. There is never a guaranteed infertility time frame for women. Some are on a very reliable cycle but there is always a chance of a odd firing off from an ovary.

Pregnancy can occur from intercourse a day or two prior to ovulation up to several days after.

If you're trying to get pregnant, have sex every day for two weeks, starting after menses stops. With a bit more study and knowing when the woman regularly ovulates you can narrow than down to 5 days.

If you don't want to get pregnant, but are still gonna have sex, - use a condom.

Last edited by pan1; 11-06-2009 at 08:41 AM..
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  #5  
Old 11-06-2009, 08:45 AM
The Piranha Brothers The Piranha Brothers is offline
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Isn't there sometimes a slightly increase in body temperature when the most fertile moment approaches?

Hey, I have a brilliant idea! The one who writes the best reply will get the OP's child named after him/her!
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  #6  
Old 11-06-2009, 08:55 AM
Sragde Sragde is offline
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Quote:
If you're trying to get pregnant, have sex every day for two weeks, starting after menses stops.
Pan1, I'm a male, all right?

And this is just a theoretical, NOT a personal question. I use a condom either, JerseyFrank.
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  #7  
Old 11-06-2009, 09:01 AM
Sragde Sragde is offline
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Quote:
The only requirement is that a single swimmer make his way to and fertilize an egg
No, not really. Even during in vitro fertilization you have to have plenty of those. As I mentioned in the question post:
Quote:
the capacity of one spermatozoid for getting through the coats and membrane of the egg is not sufficient and other spermatozoids are required for their enzymes to help dissolving the coats.
The spermatozoids are like knights-intruders and the egg is like a castle or a fortress. All the knights are needed for ''braking in'', but only one gets the princess.

Last edited by Sragde; 11-06-2009 at 09:01 AM..
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Old 11-06-2009, 09:27 AM
KneadToKnow KneadToKnow is offline
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Sperma?
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  #9  
Old 11-06-2009, 09:38 AM
Sragde Sragde is offline
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Originally Posted by KneadToKnow View Post
Sperma?
Oh, sorry. My English isn't perfect. I meant ''sperm'' or ''semen''
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  #10  
Old 11-06-2009, 09:46 AM
rhubarbarin rhubarbarin is offline
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It only takes a few sperm reaching the egg to get pregnant (I've seen several videos of the moment of conception, and it seems to be 5-15 sperm that get there first, and one is accepted), so a droplet of semen carrying a million sperm is 'enough'. The more semen, the higher the chances I suppose, but a tiny bit is surely sufficient. I know plenty of women who have gotten pregnant from just a bit.

According to a recent study published in Contraception magazine, timely withdrawel is 2% less effective than proper condom use at preventing pregnancy. It has been proven there is no sperm present in pre-ejaculate fluid - although if the man hasn't urinated since the last time he came, there could be a few.

http://www.nytimes.com/2009/07/21/health/21cond.html

I've been using withdrawal as my sole method of 'BC' for 4 years and have never been pregnant. I would not use it if I was less comfortable with the idea of an unplanned pregnancy, though.

As for the other question - that gyn is nuts. I usually ovulate 14-15 days after the first day of my last period, and earlier ovulation is possible for me and routine in other women. Sperm can live up to 5 days in the proper conditions, so that would put me right the in the danger zone. 24 hours after ovulation has occurred is when you are safe. But most women do not know when they ovulate.

Last edited by rhubarbarin; 11-06-2009 at 09:47 AM..
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  #11  
Old 11-06-2009, 09:49 AM
Thudlow Boink Thudlow Boink is offline
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Originally Posted by rhubarbarin View Post
I know plenty of women who have gotten pregnant from just a bit.
Out of curiosity, how do you know?
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  #12  
Old 11-06-2009, 10:04 AM
Sragde Sragde is offline
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Here's an answer I got outside this Message board:

Quote:
The spermatozoid has to meet the egg in precise time - while it's already (and still) in the Fallopian tube. If the spermatozoid has reached the uterus a week before the ovocyte has gone out of ovarium (if we presume that the mean survival of a spermatozoid in woman's genital tract is 2 days), then the pregnancy won't occur.

But as to the ''safe days'', it might be that pregnancy might not occur few days before menstruation (when it is clear that the ovocyte is going to ''die'') and a week after the menses have ceased (few days before ovulation). BUT the ovulation may vary in the interval of +/- 7 days. And individual survival of spermatozoids and ovocytes vary, as well. So only for woman with a regular cycle it is relatively ''safe'' to use calendar method.

Last edited by Sragde; 11-06-2009 at 10:08 AM..
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  #13  
Old 11-06-2009, 10:08 AM
Polycarp Polycarp is offline
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I recall reading that there is some evidence that the presence of multiple sperm cells and the pH of the seminal fluid plays a role in the receptivity of the ovum to fertilization. So while it's technically true that it takes only one sperm(-atozo÷n) to impregnate, the presence of multiple cells and the fluid in which they are ejaculated also plays a role.
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  #14  
Old 11-06-2009, 10:14 AM
Sragde Sragde is offline
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Originally Posted by Polycarp View Post
I recall reading that there is some evidence that the presence of multiple sperm cells and the pH of the seminal fluid plays a role in the receptivity of the ovum to fertilization. So while it's technically true that it takes only one sperm(-atozo÷n) to impregnate, the presence of multiple cells and the fluid in which they are ejaculated also plays a role.
EXACTLY! That's juts what my professor said
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  #15  
Old 11-06-2009, 11:23 AM
dhkendall dhkendall is offline
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Originally Posted by The Piranha Brothers View Post
Isn't there sometimes a slightly increase in body temperature when the most fertile moment approaches?

Hey, I have a brilliant idea! The one who writes the best reply will get the OP's child named after him/her!
Great, how'd you like go through life named Triskadecamus, The Piranha Brothers, rhubarbarin, Thudlow Boink, or Polycarp?

(NOTE: This response is just based on the user names that would make bad choices for real life names and is not meant to be seen as poking fun at the user names, or to suggest that their reply would be the potential "best".)
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  #16  
Old 11-06-2009, 11:29 AM
badbadrubberpiggy badbadrubberpiggy is offline
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Originally Posted by The Piranha Brothers View Post
Isn't there sometimes a slightly increase in body temperature when the most fertile moment approaches?
.

You're thinking basal body temperature, which rises AFTER ovulation. If you're trying to get pregnant, and wait to have sex until after you're temp rises, you're too late. It's used to confirm ovulation, not predict it.

Movies get this (among other things) wrong. Understanding your bbt means taking your temperature every morning, at about the same time, without talking or getting out of bed. So when you see movies where women are runing around with thermometers at 3 in the afternoon yelling "I'm ovulating!", they're doing it totally wrong.
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  #17  
Old 11-06-2009, 11:53 AM
Sragde Sragde is offline
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Originally Posted by dhkendall View Post
Great, how'd you like go through life named Triskadecamus, The Piranha Brothers, rhubarbarin, Thudlow Boink, or Polycarp?
I think rhubarbarin is a great name

Last edited by Sragde; 11-06-2009 at 11:54 AM..
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  #18  
Old 11-06-2009, 12:14 PM
EmAnJ EmAnJ is offline
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I'm trying to get pregnant and am having trouble, so I really, really read up on this stuff.

I'll answer the ones I know for sure: Temperature rises and the 12 days past period question.

If a woman is charting her temperature (and the temperature must be taken upon waking, before getting out of bed, at the same time every morning, after a minimum of three full hours of sleep.), and she is ovulating, she will see a slight temperature rise the day following ovulation. This is because following ovulation, your body starts producting progesterone in anticipation of a pregnancy, and progesterone raises your temp. The rise in in the hundreths of a temp point, so you use a thermometer that reads to two decimal points. The temperature stays elevated until the woman (not pregnant) gets her period and the temp drops. The cycle begins again.

This method of tracking ovulation is only usefull after the fact. You only see the rise after you ovulate, so using it as a method of birth control is useless unless you track for a few months to determine your average fertile period. Same goes for trying to get pregnant - you track for a while, determine your fertile period, and time intercourse for then.

The 12 day thing - I am really not sure where that number comes from, and that's untrue. I'll use myself as an example of why this could be disasterous if you're trying to avoid a pregnancy.

I ovulate on day 14 of my cycle, on average (I have 18 months of temperature tracking in the database). Sperm can live for up to five days in ideal circumstances. My husband and I could, theoretically, have sex on day 9 of my cycle, his sperm live for five days, get up in to my fallopian tubes, and fertilize as the egg drops. So, for us, sex after day 9 could mean pregnancy. The caveat is that some women ovulate much earlier then me, say day 9. If she has a five day period, and she has sex on the fourth day of her period, theoretically, she could still get preganant (sperm live for five days to day 9, she ovulates, bam, baby!).

Also, we've learned that having sex every day during a fertile period isn't always the answer, especially in some cases of male-factor infertility. If he has only a few swimmers, it's best to do it every two days to allow time for build up of little guys. Too much can deplete the supply, giving them less of a chance of surviving the swim.

Last edited by EmAnJ; 11-06-2009 at 12:17 PM..
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  #19  
Old 11-06-2009, 12:52 PM
badbadrubberpiggy badbadrubberpiggy is offline
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Originally Posted by EmAnJ View Post

The 12 day thing - I am really not sure where that number comes from, and that's untrue. I'll use myself as an example of why this could be disasterous if you're trying to avoid a pregnancy.
.
And completely useless if you're trying to get pregnant.

I usually ovulate around day 18, and this month not until day 25 (an odd one).

Now, I'm trying to get pregnant too, but if I went with the 12 (or 14, which I see sometimes) day "rule", I'd be timing sex for days when I'm not at all fertile, and not close enough to ovulation.

It's a bad number to use all around, since there's no way of knowing if it's accurate for you unless you're tracking your temperatures, and other fertility signs.
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Old 11-06-2009, 12:56 PM
EmAnJ EmAnJ is offline
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Originally Posted by badbadrubberpiggy View Post
And completely useless if you're trying to get pregnant.

I usually ovulate around day 18, and this month not until day 25 (an odd one).

Now, I'm trying to get pregnant too, but if I went with the 12 (or 14, which I see sometimes) day "rule", I'd be timing sex for days when I'm not at all fertile, and not close enough to ovulation.

It's a bad number to use all around, since there's no way of knowing if it's accurate for you unless you're tracking your temperatures, and other fertility signs.
This is true too.

Also, even using an Ovulation Predictor Kit can't guarantee anything, because some women gear up for ovulation (positive on the OPK), then for some reason she doesn't O and ends up Oing later, or not at all.

Last edited by EmAnJ; 11-06-2009 at 12:57 PM..
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  #21  
Old 11-07-2009, 04:06 AM
[cc] [cc] is offline
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It seems that no one ever really wants to answer the question of pregnancy likelihood throughout the menstrual cycle. It's always THERE'S NEVER A GUARANTEE YOU CAN TOTALLY GET PREGNANT ANY TIME YOU BETTER USE A CONDOM AND YOU SHOULDN'T EVEN HAVE ASKED IN THE FIRST PLACE YOU PHILANDERING SCOUNDREL.

Surely somewhere there must be a graph of at least a rough estimate or mean average of the statistical likelihood of conception occurring from non-withdrawal vaginal intercourse for any Nth day of the cycle?
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  #22  
Old 11-07-2009, 08:56 AM
kanicbird kanicbird is online now
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How many lotto tickets do you need to win the lottery? One single ticket can do it, 1,000,000 would seem to increase your chances quite a bit.
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  #23  
Old 11-07-2009, 09:02 AM
kanicbird kanicbird is online now
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Originally Posted by [cc] View Post
Surely somewhere there must be a graph of at least a rough estimate or mean average of the statistical likelihood of conception occurring from non-withdrawal vaginal intercourse for any Nth day of the cycle?
If you look into fertility awareness uses for people who want to get pregnant they have some of that info, but cycles are so variable from woman to woman and from month to month. In fertility awareness one tries to establish a basic understanding on their cycle including ovulation and something to do with vaginal fluid that is more conducive to allow sperm to reach and enter the uterus that is specific to them. It goes into the bast time to have sex to give one the greatest chance of conception. One may be able to reverse engineer this, but make a mistake this way and you will end up with a child, as opposed to just having to try again next month.
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Old 11-07-2009, 09:15 AM
rhubarbarin rhubarbarin is offline
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Originally Posted by [cc] View Post
It seems that no one ever really wants to answer the question of pregnancy likelihood throughout the menstrual cycle. It's always THERE'S NEVER A GUARANTEE YOU CAN TOTALLY GET PREGNANT ANY TIME YOU BETTER USE A CONDOM AND YOU SHOULDN'T EVEN HAVE ASKED IN THE FIRST PLACE YOU PHILANDERING SCOUNDREL.

Surely somewhere there must be a graph of at least a rough estimate or mean average of the statistical likelihood of conception occurring from non-withdrawal vaginal intercourse for any Nth day of the cycle?
Because cycles are so variable between women and even from month to month in individuals - there really isn't any way to average this information. A 'textbook' cycle is 28 days, 4-5 day period, with ovulation occurring on day 14, 15, or 16. This is what gyns base their treatment on, this is how they date all pregnancies (and will usually refuse to change your due date even if you are absolutely certain you ovulated very early or late). But the women who have a cycle timed this way are a minority (I have no idea if it's 10% or 49%, just that no one I have ever heard discuss their cycle has a 28-day blah blah cycle).

The only real way to know when you're 'safe' is to track your cycle and become familiar with signs of ovulation so you can reliably determine if you have or have't yet. Really any time before you are sure you have ovulated could be a risk, although with religious morning temping you can usually tell a few days in advance when it will occur. A day after ovulation, until your next period, you are completely safe.
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  #25  
Old 11-07-2009, 10:06 AM
EmAnJ EmAnJ is offline
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Originally Posted by rhubarbarin View Post
...although with religious morning temping you can usually tell a few days in advance when it will occur. A day after ovulation, until your next period, you are completely safe.
Only if you temp over a number of months to get your average fertile window. A temp rise occurs after you ovulate.

Last edited by EmAnJ; 11-07-2009 at 10:06 AM..
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  #26  
Old 11-09-2009, 03:18 AM
The Piranha Brothers The Piranha Brothers is offline
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Originally Posted by dhkendall View Post
Great, how'd you like go through life named Triskadecamus, The Piranha Brothers, rhubarbarin, Thudlow Boink, or Polycarp?

(NOTE: This response is just based on the user names that would make bad choices for real life names and is not meant to be seen as poking fun at the user names, or to suggest that their reply would be the potential "best".)
Polycarp is a real name, although no longer in use: http://en.wikipedia.org/wiki/Polycarp.

Anyway, I have heard of much worse names being given to children. Chastity, Felony, Misty Liberty Day, http://www.google.nl/search?hl=nl&so...meta=&aq=f&oq=
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  #27  
Old 11-09-2009, 03:52 AM
rockypg rockypg is offline
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Originally Posted by kanicbird View Post
How many lotto tickets do you need to win the lottery? One single ticket can do it, 1,000,000 would seem to increase your chances quite a bit.
I like this answer.
"In theory there's no difference between theory and practice. In practice there is."
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