Wednesday, October 31, 2007

Does the Pill encourage teenage sex? No.

Apologies, this is likely to be a long one

Executive Summary

Blogging on Peer-Reviewed ResearchYou're a busy person, Gentle Reader, so here's the scoop: after a discussion over at Illinipundit, I went looking in the peer-reviewed literature to find out whether or not access to oral contraception increased sexual activity in teenagers. Basically, I was trying to find out whether making oral contraception available encourages teenagers to have more sex. I couldn't find much of anything specifically limited to the Pill, but found quite a lot on contraception in general.

The undeniable conclusion is that access to contraception does not increase sexual activity in teenagers. Similarly and not surprisingly, access to sexual education about contraception also does not increase sexual activity in teenagers. If anything, comprehensive sexual education delays the onset of sexual activity and increases the use of contraception and condoms.

Background

Over at Illinipundit, there was a discussion about a public middle school in Maine with a health clinic that decided to proscribe birth control pills to its sexually active students. Some quick factoids from the NY Times article: there are about 500 students in the school, 135 have the parental permission required to use the clinic, 5 of those were sexually active, and they were all either 14 or 15 years old.

The scope of the teen pregnancy problem is stunning: over 40% of teenage girls are pregnant at least once by the time they're 20. (Kirby) Furthermore, a quarter of sexually active teenagers contract an STD each year. (Kirby)

In the discussion at IP D. Boon asked this:

I would really like to see some of these studies that show the prevalence of The Pill has not led to increased sexual activity at a young age. I have no qualms about saying abstinence only education is probably a not effective, but I've head the opposite about the pill.

Now, I'm pretty sure the research shows that access to contraception does not increase sexual activity in teenagers, but most of what I could remember was about condoms, not the Pill. So I went to look for the actual information.

D. Boon and redstatewannabe both also said that contraception being made available would constitute an "endorsement" of the situation. It was never really explained what that meant, specifically, but I take it to mean that it would have the effect of encouraging teenagers to have sex at a young age.

Methodology

Google Scholar. Really, that's about it. I searched for various combinations of "oral contraception", "the pill", "birth control", "contraception", "sexual activity", "teenager", "adolescent", and similar terms. I found several of what looked like good papers, read them, and followed their references to papers they cited.

I want to make it clear this wasn't an exhaustive or comprehensive search. Google Scholar isn't the best database out there, and finds lots of extraneous stuff. I'm a scientist and engineer; the databases I usually use don't index this sort of social science material. I know there are other databases like Pubmed and Medline, but I don't know how to use them. I also want to make it clear that I'm not a social scientist, so I'm generally relying on the analysis of the authors (I really don't understand how p-values and statistical significance work). Nor did I want to spend more than an hour or two (or five, by now) on this, so I limited myself to less than a dozen papers.

My search was limited to published, peer-reviewed information and their citations. I specifically did not want to rely on any press reports because they almost inevitably over-simplify the science or get it plain wrong.

Findings

In short, neither access to contraception nor sex ed that discussion contraception hasten the initiation of sexual activity. (Committee, Kirby) Everything I found supported that conclusion. It was unanimous. Kirby even describes the amount of evidence supporting this conclusion as "overwhelming."

I was not able to find data specifically limited to the Pill, but part of that may be due to the fact that there are currently at least thirteen different contraceptive methods available, including three different formulations of the Pill. Most studies looked at contraception generally, one I found looked specifically at the effect of condoms on behavior, in the context of HIV prevention.

One thing that became clear is that access to contraception isn't enough. Access to information and education is also very important. Zabin found that access to a health clinic that sounds very similar to the one in Maine (access to sexual education, counseling, and access to contraception and medical services) actually resulted in a significant delay in the onset of sexual behavior. Quoting the study:

While the changes in the age at first intercourse are not large, they are substantial enough -- in the direction of delay -- to refute charges that access to such services as those provided by the program encourages early sexual activity... The project appears to demonstrate that if students in junior high schools are given access to nearby services and if they are offered information and continuity of care, they will use such services, and at levels comparable to those shown by older teenagers.

It usually takes about a year for an adolescent female to seek contraceptive services after the onset of sexual activity. (Committee) The Zabin study found that with one year's access to the program, a female student was about twice as likely to have sought out such services before becoming sexually active, and the percentage at six months was 70%. In other words, it is important that sexual education and contraceptive access start before the onset of sexual activity. The median age for this onset in the Zabin study was about 15. (Admittedly, this was a study in an urban high school, were it is likely to be younger than elsewhere.)

Guttmacher et al. did a study on the effect of the condom distribution program started in 1991 in all New York City schools. This was done in the context of HIV prevention, but their results should be relevant in this discussion of sexual activity as well. They found:

Clearly, making condoms available at school does not lead to increases in sexual activity.

Furthermore,

higher-risk students reported getting a condom from school in significantly higher proportions than lower-risk students.

There was also some concern raised in the IP discussion about the confidentiality of these medical services. Several commenters felt that not informing parents that their children were sexually active was a violation of their "parental rights." According to the Committee report:

The primary reason adolescent's [sic] hesitate or delay obtaining family planning or contraceptive services is concern about confidentiality.

In other words, the best way to make sure teenagers do not use birth control or condoms is to tell their parents. I understand the concern here, but a parent's rights over an adolescent are not absolute. It is the moral and ethical duty of any health care worker to care for his patient's medical needs first; the abrogated rights of a third party are a secondary concern. This isn't to say they're unimportant, as in the case of mandatory reporting of rape or abuse, but a teenager above the age of consent has some medical privacy rights.

Conservatives have been pushing for abstinence-only sex education for some years now. There's even a new TV ad pushing parents to tell their children to not have sex. Personally, I think this is stupid. Not only does it completely ignore the existence of gays and lesbians, not only is it a practice that isn't used by 90% of the American population, and not only is it the only instance I know of where mandated ignorance is a form of education, but there's this to consider:

About 26% of adolescent couple trying to abstain from intercourse will become pregnant within 1 year. [Committee]

Conservatives usually inflate and distort condom failure rates when they try to claim they're ineffective, but they never cite the failure rate for their abstinence programs. Over one quarter of abstinent teenage couples get pregnant within a year, and that's not counting the couples that fail at abstinence and don't get pregnant!

Lastly, I just want to point this out to parents that still look down on sex education and contraception. This has got to be one of the most frightening statistics I've seen:

First intercourse was nonvoluntary for 9 percent of teen females. This percent was higher among those who were younger at first intercourse. (Abma)

If that doesn't make you think "Holy crap!", what does? I'm not quite sure if the use of the word "nonvoluntary" means some of these girls were just pressured into having sex as opposed to out-and-out rape, or if that's just scientific jargon for rape, but it's a stunning percentage. One in ten.

Mind you, that's just for first intercourse. One in four women will be raped in their lifetime. I can't find statistics that break it down any further, but women between 16 and 25 years old are at more than three times the risk of women in any other age group, and about 20% of women are raped by the time they're college-aged. It's sort of out of the scope of this blog post, but remember that women are not the only ones at risk. Six percent of rape victims are men, and in about 10 percent of both rape attempts and sexual assaults, men are the victims.

Conclusions

The literature conclusively states that access to contraception does not hasten the onset of sexual activity. Access to a comprehensive sex ed program as well as contraception actually seems to delay sexual activity in teenagers, if they get it early enough.

References

  • Abma, J. C., G. M. Martinez, W. D. Mosher, and B. S. Dawson. "Teenagers in the United States: Sexual Activity, Contraceptive Use, and Childbearing." Advance Data from Vital Health and Statistics. Series 23. Number 24 (2004).
  • American Academy of Pediatrics Committee on Adolescence. "Contraception and Adolescents." Pediatrics 104. 1161 (1999).
  • Guttmacher S., L. Lieberman, D. Ward, N. Freudenberg, A. Radosh, and D. Des Jarlais. "Condom Availability In New York City Public High Schools: Relationships to Condom Use and Sexual Behavior." American Journal of Public Health. 87. 1427. doi:10.1542/peds.104.5.1161 (1997).
  • Kirby, D. "Emerging Answers: Research Findings on Programs to Reduce Teen Pregnancy (Summary)." Washington, DC: National Campaign to Prevent Teen Pregnancy (2001).
  • Mosher, W. D., G. M. Martinez, A. Chandra, J. C. Abma, and S. J. Willson. "Use of Contraception and Use of Family Planning Services in the United States: 1982–2002." Advance Data from Vital Health and Statistics. No. 350 (2004).
  • Zabin, L. S., M. B. Hirsch, E. A. Smith, R. Streett, and J. B. Hardy. "Evaluation of a Pregnancy Prevention Program for Urban Teenagers." Family Planning Perspectives 18. 119 (1986).

9 comments:

Fig said...

This is actually well documented in the contraceptive, public health, public policy, and adolescent health literature. No one who works in any of these fields would disagree with the conclusions of your google search.

From: Chaney A. Myths about oral contraceptives: Does OC availability result in increased sexual activity among teens? Contracept Rep. 1993 Nov;4(5):12. "Some say the increased availability and acceptance of oral contraceptives is directly related to an increase in sexual activity among teens. However, less than 50% of women use a contraceptive method at first intercourse. Oral contraceptive use is very low and use at first intercourse has not increased over time. It is only after the establishment of routine sexual intercourse that the pill becomes the preferred method. The increase in teen sexual activity over the years does not coincide with an increase in pill use."

I've sent you a literature search of 53 articles published in peer reviewed top-tier journals within the last 5 years that say the same thing you found in your search. Feel free to post the links on narciblog or ask for PDFs of them if you can't get them electronically through your university.

Unfortunately, many of those that who think that availability of contraception suddenly turns teenagers into rampaging sexual beasts are not interested in hearing the facts. They are far more interested in the "truthiness" of what they already think.

prairie biker said...

good work. thanks.

Anonymous said...

It is interesting that the first commenter, "fig" cited a study that said less than 50% of women use a contraceptive the first time they have sex. It took me two minutes to find these facts:

•The majority of sexually experienced teens (74% of females and 82% of males) used contraceptives the first time they had sex.[11]

•The condom is the most common contraceptive method used at first intercourse; it was used by 66% of sexually experienced females and 71% of males.[12]

•Nearly all sexually active females (98% in 2002) have used at least one method of birth control. The most common methods used are the condom (used at least once by 94%) and the pill (used at least once by 61%).[13]

•Nearly one-quarter of teens who used contraceptives the last time they had sex combined two methods, primarily the condom and a hormonal method.[14]

•At most recent sex, 83% of teen females and 91% of teen males used contraceptives. These proportions represent a marked improvement since 1995, when only 71% of teen females and 82% of teen males had used a contraceptive method at last sex.[15]

http://www.guttmacher.org/pubs/fb_ATSRH.html

Yes, how 'bout those of us who hate it when facts get in the way of our "truthiness". That *is* a problem, isn't it.

Fig said...

Anon,

The guttmacher institute is a great place to get facts and a research powerhouse on sexual and reproductive health. I'm glad that you know about them.

I think you possibly misunderstood my quote. I was using the quote from Cheney to illustrate that, as of 1993, there was no correlation between use of oral contraceptive and age of first initial coitus.

With increasing awareness about preventing sexually transmitted diseases, I'm not at all surprised that adolescents would choose to use condoms. The Guttmacher site lends credence to that: The proportion of women who used a contraceptive method the first time they had sex has nearly doubled, from 43% in the 1970s to 79% in 1999-2002. The change is mostly due to an increase - from 22% to 67% - in the proportion using the male condom at first sex (Mosher WD et al., Use of contraception and use of family planning services in the United States: 1982-2002, Advance Data from Vital and Health Statistics, No. 350. 2004). The numbers you quote from Guttmacher (although it would have been more helpful if you had included the actual citations as opposed to solely the reference numbers) seem to be much closer to what I see in my practice as a physician than what was reflected in the Cheney article. That is exactly why I offer Narc the 53 more current articles.

None of the quotes you pulled from Guttmacher, however, imply that using oral contraceptives (or any contraceptive method) leads to a younger initiation of coitus. In fact, three of the five quotes you provided have nothing to do with first intercourse experience. All five of the quotes seem reasonable and plausible to me and I do not disagree with any of them.

The Guttmacher Institute has some methodologically rigorous work http://www.guttmacher.org/pubs/journals/2801996.pdf
(That's: Mauldon J and Luker K. The Effects of Contraceptive Education On Method Use at First Intercourse Family Planning Perspectives, 28:19–24 & 41, 1996 if the link doesn't work)that shows that teens who receive education about contraceptive methods are statistically more likely (p-value < 0.001, so highly statistically significant) to use contraception when they first have sex and more likely to postpone event of first intercourse (From Table 2: age 17.2 at first coitus w. education, age 15.6 without contraceptive education)

This is the sort of work that the Guttmacher Institute has consistently brought to the world's attention. I am glad that people outside the world of medical and policy academia are aware of them.

moon_grrl said...

Nice work to both narc and fig! Y'all rock.

Anonymous said...

So you don't actually agree with the Chaney article that you quoted extensively in support of Narc's point? Strange. I guess I wonder why you quoted it in the first place?

You are correct that there are no studies that link the loss of virginity to the availability of contraception. Of course one could imply from the fact that so many of these teens used contraception during their first sexual experience that perhaps the availability of the contraception had something to do with it being "ok". But in the absence of studies to prove the truth of that claim I guess we can't really say that.

Of course we can't really say the opposite either, can we?

Which is perhaps the point here. I have no problem with sex education. No problem with schools teaching kids how to use condoms. I don't even have a problem with schools and the state providing oral contraceptives to students with parental permission.

I have a problem with the school providing oral contraceptives to underage girls without parental consent. As a physician you must be familiar with the large number of studies that link the use of oral contraceptives to a variety of health risks, from increases in breast cancer and strokes to fertility issues. If my neighbor wants to buy her daughter OCs I have no problem with that. But as a parent *I* want to be the one to say "yes" or "no" to any medications that are given to my child. I have a serious problem with the state, the school nurse, or even my child's physician making that choice for me. Until she is 18 she is my child and I want to make sure no doctor or nurse gives her something that could send her immature body into unnatural territory.

Narc said...

Anon, this isn't Illinipundit, this is a blog mostly visited by my friends. I'll ask you to be a bit more polite.

Anyway, your statement "one could imply from the fact that so many of these teens used contraception during their first sexual experience that perhaps the availability of the contraception had something to do with it being 'ok'" doesn't hold up. That's the very thing I was researching. If you'll look again at what I cited, you'll see that the availability of contraception doesn't decrease the age of first sexual activity.

David said...

Anon, this isn't Illinipundit, this is a blog mostly visited by my friends. I'll ask you to be a bit more polite.

Not to mention stop flinging attitude around from behind the cover of "Anonymous".

If you're so sure of your position, be brave enough to put your name and reputation on the line. For me, in the on-line world of blogs and comments, "anonymous" equals "coward."

Brijesh Kumar said...

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