Emergency contraception

[lederhosen]

Meant to link to this ages back, never got around to it: How Does Emergency Contraception Work?

The article goes into more detail, but I'll summarise and embellish:

When does human life begin, and what does this mean for family planning? If you believe that it starts at 'first breath', you're going to come to some different conclusions from the person who believes that it begins when the heart starts beating, or when an embryo implants, or when the egg is fertilised. Or, for that matter, the person who believes it's wrong to even attempt to prevent pregnancy when having sex.*

I'm not going to argue that issue just now. Instead, I'm going to take it for granted that most of you already have some sort of position on that, and run with what you do believe. (In particular, most of what follows is chiefly relevant to those who put it at somewhere around 'egg is fertilised' or 'embryo implants'.)

Because, as hard a question as 'when does life begin?' might be, it's only half of the equation.** The other half is 'when do family planning methods act?' This is in some ways a much easier question that can be answered by scientific means, but it's still complicated enough that there's a lot of confusion and misinformation doing the rounds.


Fertilisation requires the combination of viable sperm and viable egg. The egg is released at ovulation, and remains viable for about a day afterwards. I think we all know how sperm enter the picture, and they stay viable for about five days afterwards. The result of this is that fertilisation can happen if ovulation happens as early as one day before sex, or as late as five days afterwards.

I'll say that again, because it's important: fertilisation doesn't necessarily happen the moment you have sex. Depending on the timing, the egg might already be there... or the sperm might be hanging around for five days waiting for it to show up.

What this means is that if you can prevent ovulation, even after sex, you have quite a good chance of preventing fertilisation from ever happening. And this is how things like 'Plan B' work: they interfere with a woman's hormonal balance in order to prevent ovulation. (BTW, this is a big part of why they're far from 100% reliable: if you take them after ovulation's already happened they're not going to do much, and although they can certainly reduce the chance of pregnancy even if taken several days afterwards, the longer you leave it the less likely they are to work.)

I'll grant, hormones are complicated things. It's hard to absolutely rule out the possibility that one or more of the emergency contraceptive pill (ECP) formulations *might* act to block fertilisation, or might make the fertilised embryo less likely to implant. But with one exception that I'll get to in a bit, there doesn't seem to be any solid evidence that this happens. To quote this study published by the American Association of Family Physicians: "Some individuals may consider these hormones to be abortifacients if they interfere with implantation. However, the proven mechanisms of action consist of inhibiting or delaying ovulation. These hormones will not dislodge an implanted embryo."

If you think the possibility of interfering with implantation is enough to make ECPs objectionable, so be it - but be aware that this is only a possibility, not by any means a confirmed effect. (And be prepared to apply the same standard to other, non-ECP drugs that might also, for all we know, potentially interfere with implantation.)

One major cause of confusion is that one of the drugs that can be used as an ECP also has another well-known use. A 10-mg dose of mifepristone, aka RU-486, works as an ECP by preventing ovulation. (It may also discourage implantation, but I'm not sure if the 10-mg dose is enough to do this; larger doses certainly can, but the sources I can find are fuzzy on how much it takes. It doesn't appear to interfere with an already-implanted embryo.) A 600-mg dose of the same stuff will induce abortion, even when the embryo is already implanted. It's important to understand that the mechanism of action - and hence the moral implications - depend on the dose here; if you're opposed to the use of the 600-mg dose of RU-486 as an abortifacient, that's your call, but don't fall into the trap of thinking that a 10-mg dose RU-486 as an ECP is the same moral issue. By way of parallel, taking two paracetamol tablets for a headache is a very different thing, medically and morally, from taking a hundred and twenty of them.

(According to the AAFP article I linked above, the main use of RU-486 as an ECP is in China. It's available for this purpose in the USA, but only as an off-label use, and because the on-label use involves 3x200mg tablets, it can't be had in less than a 200mg dose - even though 10mg seems to work just as well for ECP purposes. I don't know what the effects of a 200mg dose on an implanted embryo are.)


*FWIW, my own stance is a rather involved 'none of the above, because I reject the entire premise of this question', but let's save that for some other day.
**Actually, it's really an inequation, but that also is for another day.

Comments

[bunny-hugger.livejournal.com]

I reject the question too, because I think that ethical questions should deal with personhood (a moral concept) rather than humanity (a biological concept).

[cornute.livejournal.com]

"It's hard to absolutely rule out the possibility that one or more of the emergency contraceptive pill (ECP) formulations *might* act to block fertilisation, or might make the fertilised embryo less likely to implant. But with one exception that I'll get to in a bit, there doesn't seem to be any solid evidence that this happens."

Thanks. With the amount of rhetoric flying around, especially here in the Christianity-heavy part of the country, it's hard to find what things actually do, or at least what we think they do.

Mind sharing why you use the term "family planning" to refer to contraception?

[lederhosen.livejournal.com]

I wanted a broader term that could also encompass abortion. Ordinarily I'd be quite happy to refer to ECPs as 'contraception', but since that was the point of this post I didn't want to start by begging the question. Also, mifepristone can be either contraception or abortion depending on how it's used, so 'family planning' seemed better for encompassing all that.

In hindsight, 'birth control' might have been a better term, but it just didn't spring to mind when I needed it.

[frou-frou.livejournal.com]

Perhaps because in Australia, "family planning" is used as an acceptable euphemism for "birth control". You've got me wondering if this is the case in other countries?

[cornute.livejournal.com]

Well, "family planning" equals birth control PLUS using some of the same things to try to conceive (e.g. monitoring your basal body temp can be used for not getting pregnant, or for getting pregnant). Basically, it's the idea that you are "planning your family," meaning your future children. I think you can see how this idea goies "sproing" when it meets the childless-by-choice crowd-- if you aren't going to have children, then referring to the methods you take to ensure you DON'T get them as planning TO get them is really silly! It's like referring to atheism as "what you believe about God."

What we need is a good word for "practicing hedonism-only sex."

[cornute.livejournal.com]

Somehow, "birth control" seems like a better choice. :)

[krfsm.livejournal.com]

"Conception control" even. Other factors can affect between conception and birth.

[lederhosen.livejournal.com]

But I didn't want to limit it to conception control, since the term there is also intended to encompass things that might cause abortion post-conception.

[bunny-hugger.livejournal.com]

Oh, I do like a person who knows how to use the term "begging the question." :)

[lederhosen.livejournal.com]

I'm trying to use that expression as often as possible in the decade or so that we have left before its proper use is lost to the English language forever :-/

(Not that I'm opposed to the language evolving when it's for the right reasons, but 'failure to understand the existing language' isn't one of those.)

[bunny-hugger.livejournal.com]

Also, the term describes a fallacy that people use a lot; people ought to know what the term really means because they ought to be able to recognize when someone's doing it. There's no alternate term in common usage that describes the same thing. (One might claim that "circular argument" means the same thing, but I don't think it does quite.)

[waitingman.livejournal.com]

This is a difficult one - for most of, if not all of the reasons stated.

It raises the rhetorical question(s) of where personal belief &/or understanding, should be allowed to influence (or interfere) with legislation &/or regulation... let alone what role religious or philosophical doctrines could, or should, play...

What should the law/regulation/rule be?? Should there even be a law/regulation/rule??? What moral, ecological, fiscal value & impact does/should one place on a new life - whenever you think it starts???? So who chooses?

Let the can of worms be opened.

[winterkoninkje.livejournal.com]

Thanks for the post. It's nice to get some level-headed presentation that has to do with, oh y'know, biology instead of just the right-wing's rhetorical contemplations on what they think might be biology.

[psychowoof.livejournal.com]

Yes, well stated - it amazes me how many people don't know how EC works (Despite the most common form of EC being heavy doses of your standard oral contraceptives. Hmm, we've figured out how those work and other than those who feel no artificial means of contraception should be used EVER, no body is screaming abortifacient about OCs.)

Now, a copper IUD as an emergency contraceptive does open a different moral can of worms. It does prevent implantation (in most cases - they're also not 100% effective) if fertilization has already occured.

And somewhat related, what really pisses me off about many anti-abortionists is that they are under the misperception that most abortions are partial-birth/late-stage that involve near-birth size fetuses. Most abortions happen in the early weeks of pregnancy when the embryonic tissues are fairly indistinguishable from the uterine lining - see Visembryo for a good visual of the actual size of the embryo at the early stages of pregnancy. (I will warn that viewing these pages and the processes of pre-natal development may change attitudes toward abortion - no, nothing is gross, it's just pretty amazing how quickly human features are developed.)

[thette.livejournal.com]

no body is screaming abortifacient about OCs

Oh, yes, they are. A large portion of the American right wing is not only anti-abortion but also anti-contraception, and this is one of their stated reasons.

[psychowoof.livejournal.com]

SIGH!!!

Now there's an argument based on false logic. I totally get being against artificial methods of birth control for religious reasons. But at least be correct in how the contraceptive works people!

See where the abstinence only sexuality education gets us? A bunch of uneducated people.

[bunny-hugger.livejournal.com]

Well, as you know, the Pill usually prevents ovulation. If there's no ovulation, then obviously there's no abortion. However, a small percentage of the time, the Pill fails to prevent ovulation. That's what the controversy is about. Some hold that the Pill causes a thinning of the uterine lining that makes it more hostile to implantation. Thus, in a few cases, the Pill might act to prevent implantation. Most people in the medical community would not regard a failure to implant as "abortion" because pregnancy is usually defined as starting with implantation. But for the hard-core pro-lifer, that fertilized egg is a "human life" and preventing it from implanting is wrong.

My understanding is that there has not been enough research to determine whether or not the Pill actually does act to prevent implantation.