Relationship in the gutter.

[flyingfish]

The statistics being stated here all kind of confuse me, but the thing I’m wonder for the stat on who got pregnant without any contraceptives, were those people not charting when they could get pregnant? Because then the two stats aren’t really comparing the same thing.

If they’re taking the stats on couples who got pregnant while trying to avoid, then it would at least be close to similar. But if they’re having sex any time of the month, then of course their pregnancy rate is going to be higher. Because they had sex during a fertile time.

I just don’t know that you can compare the two things.

The statistic on who got pregnant without using any contraceptives means they didn’t do anything and just had sex whenever.

I mentioned those statistic to compare condom use to nothing at all. Here’s some stuff for NFP: sciencedaily.com/releases/2007/02/070221065200.htm

Of the 900 women, 322 used only STM and 509 women used STM with occasional barriers during the fertile time. Sixty-nine women did not document their sexual behaviour. Out of the women who documented their sexual behaviour and abstained from sex during their fertile period (“perfect use”) the unintended pregnancy rate was 0.4 per 100 women and 13 cycles [2], and 0.6 for women who used STM plus a barrier if they had sex during their fertile period. For cycles in which couples had unprotected sex during the fertile phase, the pregnancy rates rose to 7.5 per 100 women and 13 cycles.

 

[flyingfish]

My point is still being missed entirely.

These statistics for condom use do not take into consideration that most of the time, and woman could NOT have conceived anyway. NFP stats are at least somewhat reliable because they take the fertile times into consideration.

My challege to the OP is the faith they are putting in these stats when they are outright lies… , yet the OP does not have faith in God.

I did take that into account into my calculation. I’ll explain it better:

Take 100 couples having sex for 1 year, and look only at the fertile times. I made the assumption that 10 days in each month are fertile days. I also made the assumption that couples will have sex on each fertile day. (These could be wrong assumptions, but you can adjust the calculation based on different ones.)

Based on this, each year each couple will have 120 sex acts when the woman can get pregnant. Out of the 100 couples, 2 get pregnant with perfect use of condoms.

This means 2 pregnancies out of (100 couples * 120 fertile sex acts per couple per year) gets you (approximately) the chance for each sex act.

It doesn’t matter that they are also having lots of sex on infertile days, the only thing that matters is the number of fertile sex the 100 couples have per year.

You can adjust the estimates, say the couple only has 50 fertile sex acts per year (i.e. 50 sex acts on days when the woman can get pregnant), then its 2 pregnancies / (100 couples * 50 sex acts per year per couple) and so on.

This calculation is to get the probability of getting pregnant for each single act of fertile sex.

 

[nicreap]

I did take that into account into my calculation. I’ll explain it better:

Take 100 couples having sex for 1 year, and look only at the fertile times. I made the assumption that 10 days in each month are fertile days. I also made the assumption that couples will have sex on each fertile day. (These could be wrong assumptions, but you can adjust the calculation based on different ones.)

Based on this, each year each couple will have 120 sex acts when the woman can get pregnant. Out of the 100 couples, 2 get pregnant with perfect use of condoms.

This means 2 pregnancies out of (100 couples * 120 fertile sex acts per couple per year) gets you (approximately) the chance for each sex act.

It doesn’t matter that they are also having lots of sex on infertile days, the only thing that matters is the number of fertile sex the 100 couples have per year.

You can adjust the estimates, say the couple only has 50 fertile sex acts per year (i.e. 50 sex acts on days when the woman can get pregnant), then its 2 pregnancies / (100 couples * 50 sex acts per year per couple) and so on.

This calculation is to get the probability of getting pregnant for each single act of fertile sex.

What they are saying, is unless the study was taken and the people ONLY had sex on fertile days, then the numbers will be wrong, your assumptions can’t be applied to the numbers if you don’t know the initial condition. You can’t adjust data based on assumptions so your numbers are most likely wrong. What if the condom failed half the time, but they rarely had sex on fertile days? You would have a low percent of pregnancy but that doesn’t prove that the condom is effective at working, especially comparing it to other people randomly having sex.

 

[flyingfish]

What they are saying, is unless the study was taken and the people ONLY had sex on fertile days, then the numbers will be wrong, your assumptions can’t be applied to the numbers if you don’t know the initial condition. You can’t adjust data based on assumptions so your numbers are most likely wrong. What if the condom failed half the time, but they rarely had sex on fertile days? You would have a low percent of pregnancy but that doesn’t prove that the condom is effective at working, especially comparing it to other people randomly having sex.

Well, that’s the reason they study 100 couples for a year, and the reason you need a decently large sample for the statistic to mean anything.

If you have 100 couples having sex for an entire year, it’s a fair assumption that you wouldn’t end up with a sample where by some freak accident no one had sex on fertile days.

The study would be ruined if the couples knew when they were fertile and deliberately avoided sex on those days. It depends on being able to treat the day the couples chose to have sex as a random variable.

**If you want to know what the probability of getting pregnant when you have sex with a condom on a fertile day is, you want to divide 2 by how many sex acts those 100 couples had over the course of 1 year on fertile days. **

If you want to know the probability of getting pregnant when you have sex with a condom on a random day, then you want to divide 2 by the total number of sex acts the 100 couples had over 1 year (i.e. all days, not just the fertile ones).

 

[agapewolf]

Well, that’s the reason they study 100 couples for a year, and the reason you need a decently large sample for the statistic to mean anything.

If you have 100 couples having sex for an entire year, it’s a fair assumption that you wouldn’t end up with a sample where by some freak accident no one had sex on fertile days.

The study would be ruined if the couples knew when they were fertile and deliberately avoided sex on those days. It depends on being able to treat the day the couples chose to have sex as a random variable.

If you want to know what the probability of getting pregnant when you have sex with a condom on a fertile day is, you want to divide 2 by how many sex acts those 100 couples had over the course of 1 year were on fertile days.

If you want to know the probability of getting pregnant when you have sex with a condom on a random day, then you want to divide 2 by the total number of sex acts the 100 couples had over 1 year.

These conditions don’t match up. As the pp said, applying conditions and assuming the same outcome, which is impossible, and btw, is also what the statistics are trying to say.

The other idea about 85 achieving conception is outright ridiculous.

 

[flyingfish]

The other idea about 85 achieving conception is outright ridiculous.

The 85% is again for the entire year. If a randomly chosen couple has sex without any kind of method of avoiding pregnancy for an entire year, they have an 85% of getting pregnant. Why is that unreasonable to you?

 

[nicreap]

Well, that’s the reason they study 100 couples for a year, and the reason you need a decently large sample for the statistic to mean anything.

If you have 100 couples having sex for an entire year, it’s a fair assumption that you wouldn’t end up with a sample where by some freak accident no one had sex on fertile days.

The study would be ruined if the couples knew when they were fertile and deliberately avoided sex on those days. It depends on being able to treat the day the couples chose to have sex as a random variable.

If you want to know what the probability of getting pregnant when you have sex with a condom on a fertile day is, you want to divide 2 by how many sex acts those 100 couples had over the course of 1 year were on fertile days.

If you want to know the probability of getting pregnant when you have sex with a condom on a random day, then you want to divide 2 by the total number of sex acts the 100 couples had over 1 year.

The math doesn’t work that way. It is obvious they used a poor experiment. If you are trying to test the effectiveness of a condom you remove all variables, especailly the randomness of sex. If they don’t know when they are fertile then it is possible there are couples who never had sex on a fertile day, which means the data is skewed. Unless they ran a study of people having sex only on fertile days using a condom, then any results they receive doesn’t prove anything.

The study is pointless if they just randomly have sex as well. If a woman can’t get pregnant 20 days out of a month, then testing the effectiveness of birthcontrol on any day a woman can’t get pregnant is pointless and only skews the data towards it’s effectiveness. It’s obvious these tests were poorly set up to get data that looks like it works in the favor of condom makers.

 

[agapewolf]

The 85% is again for the entire year. If a randomly chosen couple has sex without any kind of method of avoiding pregnancy for an entire year, they have an 85% of getting pregnant. Why is that unreasonable to you?

First of all, its a made up number.

2nd of all, its not true. The amount of infertility that exists, at least slight reproductive problems and issues that exist today, there is no way that is possible.

3rd: There is absolutely no way to test it. None at all. There is no way to test who would have gotten pregnant at a specific time. The number is baseless.

 

[agapewolf]

The math doesn’t work that way. It is obvious they used a poor experiment. If you are trying to test the effectiveness of a condom you remove all variables, especailly the randomness of sex. If they don’t know when they are fertile then it is possible there are couples who never had sex on a fertile day, which means the data is skewed. Unless they ran a study of people having sex only on fertile days using a condom, then any results they receive doesn’t prove anything.

The study is pointless if they just randomly have sex as well. If a woman can’t get pregnant 20 days out of a month, then testing the effectiveness of birthcontrol on any day a woman can’t get pregnant is pointless and only skews the data towards it’s effectiveness. It’s obvious these tests were poorly set up to get data that looks like it works in the favor of condom makers.

This is my point. And to add to it…even if it was tested on fertile days, it still doesn’t prove much. It might be a little more reliable, but still isn’t.

NFP, however, IS a little more reliable, because it does take into consideration infertile times vs. fertile times.

 

[agapewolf]

My whole point though again, is to the OP who wouldn’t have sex without ABC… because he put his faith in those stats that it actually works.

 

[flyingfish]

The math doesn’t work that way. It is obvious they used a poor experiment. If you are trying to test the effectiveness of a condom you remove all variables, especailly the randomness of sex. If they don’t know when they are fertile then it is possible there are couples who never had sex on a fertile day, which means the data is skewed. Unless they ran a study of people having sex only on fertile days using a condom, then any results they receive doesn’t prove anything.

The study is pointless if they just randomly have sex as well. If a woman can’t get pregnant 20 days out of a month, then testing the effectiveness of birthcontrol on any day a woman can’t get pregnant is pointless and only skews the data towards it’s effectiveness. It’s obvious these tests were poorly set up to get data that looks like it works in the favor of condom makers.

The thing with studies like this is it often is not possible to set up an experiment to control for all variables. If you decided to run a study like you suggest, where scientists determine exactly when the woman is fertile and have the couple have sex with a condom on those days (maybe they also put the condom on the guy to make sure it’s being used correctly ) you likely would not get people to participate in your study.

In other situations (like say the effects of poverty and deprivation of nutrition) it would be unethical to set up an experiment like that.

To deal with this is a huge part of the entire science of statistics. You can extract data without setting up a direct experiment as you say. There are a number of things that go into it, one of them is being able to choose a random sample.

 

[flyingfish]

NFP, however, IS a little more reliable, because it does take into consideration infertile times vs. fertile times.

Right, in the other study I linked which I will link again in case it got lost in all the numbers the perfect use statistics for the SymptoThermal method of NFP is sciencedaily.com/releases/2007/02/070221065200.htm

Of the 900 women, 322 used only STM and 509 women used STM with occasional barriers during the fertile time. Sixty-nine women did not document their sexual behaviour. Out of the women who documented their sexual behaviour and abstained from sex during their fertile period (“perfect use”) the unintended pregnancy rate was 0.4 per 100 women and 13 cycles [2], and 0.6 for women who used STM plus a barrier if they had sex during their fertile period. For cycles in which couples had unprotected sex during the fertile phase, the pregnancy rates rose to 7.5 per 100 women and 13 cycles.

0.4 per 100 women per 13 cycles (I am guessing period cycles, which amounts to a year).

This is better than a condom, and if you use the symptothermal method for your entire life (perfect use) you would expect to get an accidental pregnancy in over 100 years.

Incidentally, in this particular study a group of women used NFP and used “barrier methods” during fertile times, their rate was 0.6 per 100 per 13 cycles. This is probably as close as you’d get for testing a barrier method (not necessarily condom I guess it would include cervical caps and stuff like that too?) specifically only during the fertile times.

 

[nicreap]

And it also says only 7.5% of people having unprotected sex during fertility got pregnant. So how can you tell how effective perfect condom use is, if their numbers put pregnancy that low for unprotected sex?

 

[flyingfish]

And it also says only 7.5% of people having unprotected sex during fertility got pregnant. So how can you tell how effective perfect condom use is, if their numbers put pregnancy that low for unprotected sex?

The paragraph right after that in the study:

The authors were surprised by the relatively low rate of unintended pregnancies (7.5%) among women who had unprotected sex during their fertile period. “If people are trying for pregnancy you expect a pregnancy rate of 28% per cycle,” said Prof Frank-Herrmann. “Therefore, we think that some of the couples were practising conscious, intelligent risk-taking, and were having no unprotected sex during the few highly fertile days, but had unprotected intercourse on the days at the margins of the fertile time when the risk of pregnancy was lower.”

 

[nicreap]

But again, it is just the researches guessing at the reason. There is a reason you try and control as many variables as you can in an experiment, because every variable that is allowed leaves more and more room for the data to go astray.

But this has nothing to do with the original topic of the cnoversation. The point someone was making way back when, was that the OP will trust these experiments on how effective birth control is, when there is a lot of room for error, but he doesn’t trust in God. So he is willing to trust in the conclusions of researches, many of which are out to make a buck for companies selling contraceptives, but not something that isn’t trying to sell you anything.

The fact that he also can’t control himself during the holidays doesn’t help. He claims he means making out, but he has already admitted he can’t say no to her, and making out will probablly lead to more things in his case. As another poster stated, the parents aren’t stupid, they will have a pretty good idea as to why they are visiting her friends soo much. I would imagine they won’t be happy about it.

 

[flyingfish]

But again, it is just the researches guessing at the reason. There is a reason you try and control as many variables as you can in an experiment, because every variable that is allowed leaves more and more room for the data to go astray.

I don’t think it’s quite “guessing”, I mean, presumably when they selected the participants for the NFP study they made sure that they weren’t infertile (or had reduced fertility than the general population). Then they have other data from studies of what happens when people actively try to conceive, and from that they make their conclusions.

If the participants in the NFP study had lower fertility than the general population, that would call into question the results about the effectiveness of that NFP method. And personally I trust that the researchers did not make such a grave error when they selected participants for their study. Avoiding stupid mistakes like that probably got drilled into them in undergrad and grad programs.

The fact that he also can’t control himself during the holidays doesn’t help. He claims he means making out, but he has already admitted he can’t say no to her, and making out will probablly lead to more things in his case. As another poster stated, the parents aren’t stupid, they will have a pretty good idea as to why they are visiting her friends soo much. I would imagine they won’t be happy about it.

I don’t know, I would expect young people to hang out with their friends over the holidays. Why not? But I think he later said he was joking when he said that.

 

[monicatholic]

the stats are really tangential to the issue.

sex outside of marriage is a misuse of sex.
contracepted sex is a misuse of sex.

if Persuader refuses to investigate the Church’s reasons for these teaching, he is guilty of culpable ignorance.

 

[Persuader]

Ok. I don’t know if I should really post on this issue, as it is really irrelevant to the thread, but you people seem utterly ignorant of statistics and probability. One of you mentioned how condoms are 15% effective. At first I thought you meant by one year of use, but apparently you meant for one sex act during a fertile period. That is completely preposterous. If you wanted an accurate representation of pregnancy probabilities, you would need a complex statistical analysis with many variables. In this case, when we just decide to go with 15%, we can use binomial probability for simplicity. This does not take in to account that you are out of the race as soon as you get pregnant, but that doesn’t matter as long as you are calculating the probability of never getting pregnant.

Now, let’s say we have sex 10 times during fertile days. What would be the probability of never getting pregnant with a 15% chance each time? P(X=0) = (10 0)0.15^00.85^10 = 0.85^10 ≈ 0.19687. Let’s try with 40 days. Then we would have: P(X=0) = (40 0)0.15^00.85^40 = 0.85^40 ≈ 0.0015. You can all see where this is going… This clearly doesn’t make any sense. And then I get flak for giving statistical facts? Ridiculous.

Some of you say I trust these experiments when there is a lot of room for error. You base this on your own speculations about the distribution of data. If you were interested in finding answers to your questions, you would have to obtain some studies and see the distribution and frequency of sex acts for couples. You would also do well to notice the standard deviation in this respect. If the studies are well done, it wouldn’t surprise me if the standard deviation is low. There should be data of this in the studies, but you will probably need access to the relevant scientific journals. Until you have studied this, I wouldn’t be criticizing anything. It makes you look stupid. And by the way, I actually understand what that 2% probability means. It means that, on average, there is 2% chance of getting pregnant by one year of condom-use. Any serious deviation from the mean (regarding frequency, distribution of sex acts and other variables), will have some influence on the probability in a specific case (partly because of said variables and their impact on condom failure-rate). Nevertheless, the 2% gives you a good idea, and by my understanding it makes correct condom use pretty safe.

I saw that flyingfish posted an interesting article about the effectiveness of NFP. That is really surprising numbers. If you compare them to the numbers obtained for similar methods, there seems to be quite a discrepancy: en.wikipedia.org/wiki/Comparison_of_birth_control_methods#Effectiveness_of_various_methods

You will also notice that the contraceptive my gf is currently using (Implanon) is the most effective (along with Jadelle/Norplant).

Now, I also notice that some of you is comparing my trust of contraceptives to me trusting in God. Well, that is quite a separate issue, don’t you think? I really don’t think that is a meaningful comparison.

As far as controlling myself, I think I can manage. If me and my gf actually visit her family, we will respect their rules whilst staying there (no sex). A little heavy petting during our visit? I imagine we’ll attend at least one Christmas-party (with alcohol) with her friends. I think some petting should be expected. She’s not a nun (except when we play dress-up (to the distrustful bunch, yes this is a joke)), and I’m not a monk. I think her parents realize that.

Regarding the general question of sex and contraception, I am simply saying that I disagree with catholic teaching (obviously). I am seriously skeptical of whether the catholic view makes much sense to a non-believer like myself. My gf says it wouldn’t, and I trust her judgment. Perhaps I will get a book on it, but I don’t think I will make it a priority. If my gf were to regain her faith along with her Catholicism, I would probably have to (although in that case, I would imagine she will have to make some accommodations too, not only me. Compromise isn’t about one side getting their way on everything.).
Honestly though, if she regains her faith in God, I don’t think she will return to Catholicism. I think some form of deism or Protestantism is more likely.

 

[agapewolf]

Actually, you are making yourself look ignorant here because you have yet to address my actual point.

There are no studies done of just fertile sex acts…its impossible. My point is, which you are msising over and over and over…is that the stats of 2% per year is an outright absolute LIE…because non-fertile sex acts just sway in favor of that statistic, rather than being disregarded in the testing.

2nd…the wiki stats are wrong…sometimes they include withdrawal and rhythm method, which is NOT NFP.

3rd, petting is NOT expected, for single folks. Its morally wrong, with or without alcohol. To “Expect” it is presumption.

4th, your statistic for whatever ABC you use does not take into account the abortions that also happen from its use…so it may be actually not effective at all, but just aborting every child that is conceived.

 

[flyingfish]

There are no studies done of just fertile sex acts…its impossible. My point is, which you are msising over and over and over…is that the stats of 2% per year is an outright absolute LIE…because non-fertile sex acts just sway in favor of that statistic, rather than being disregarded in the testing.

I think the point you are missing is that 2 pregnancies per 100 couples per year assumes that the couple doesn’t deliberately select fertile or infertile days.

Presumably if the OP were to have sex with a condom, this is what he would do, so the 2% chance per year would be a good measure of risk for him.

The 2 pregnancies per 100 couples per year could only have happened when the couple had sex on a fertile day. For the purpose of finding out the chance of getting pregnant with a condom on a fertile day, you need to know how many sex acts the 100 couples had on fertile days.

The study would be bad if there were disproportionately few sex acts on fertile days, like say only 2. But, as long as this was not the case, it doesn’t matter.

Even if each couple only had fertile sex 10 times in the whole year. That’s 100 couples * 10 fertile sex days per couple = 1000. And of those 2 pregnancies. (And this is a rough estimate because once a couple gets pregnant, they can no longer have fertile sex. But since only 2 get pregnant, this difference doesn’t have an effect although it would if say all got pregnant.)