Rhythm Method

Do you think rhythm or calendar-method birth control methods are ever
worth considering for someone who does NOT want to get pregnant? I
know the mainstream word on the issue is that these methods are
generally ineffective, but their legitimacy and popularity seems to be
growing in more alternative circles in the last few years. Is this
something that the world of conventional medicine has rejected out of
a fear of the unknown, or should cycle-based methods absolutely be
avoided if you’re not willing to chance pregnancy? Do any other
effective non-hormonal birth control methods exist?

[I have edited out a couple of paragraphs of personal information on the poster.  The pertinent details: she is in a monogamous, committed relationship and is using condoms but has had some trouble with their reliability.  She used the depot shot in the past with no bad side effects, but would prefer not to be on hormones.  She is allergic to nickel.]

I apologize for the long wait on this response!  As luck would have it, I actually happened upon an expert opinion on the matter today!  The nurse and lactation consultant I see at my mothers' group used to coach people in natural family planning.  Just by chance, she brought it up today so I got to pick her brain about it.

There are different ways to use natural family planning.  You use the term Rhythm, and this is technically just the calendar method of birth control where you chart your periods, count out the days from your last period to estimate your ovulation date, and remain celibate around this time of your cycle to prevent pregnancy.  There are various ways of counting and various tools for reminding you what day you're on.  You have to be celibate for up to 14 days out of your cycle, which is a long time, and perfect use gives annual failure of about 5-10% (according to Wikipedia and that oft' quoted table that is printed on all birth control pill pamphlets).  This method relies on a cycle like clockwork and   Regular use gives up to 25% failure rates (according to the same table and the Mayo website).  That isn't great -- worse than condoms and much worse than hormonal methods of birth control.  It's even worse than the pull-out method.  It is decidedly better than nothing (85% of women using no birth control get pregnant in a year), however I think it is not a suitable method of birth control to be used if you really want to protect yourself well from pregnancy.

There are ways to improve your results without introducing synthetic hormones, IUDs, or condoms.  The Sympto-Thermal method of birth control is more accurate, less reliant on a regular cycle, allows for more days of sex, and gives much better results than the calendar method alone.  This is very similar to the calendar method of BC, but instead of just counting days and poking your finger at a likely ovulation date, you develop a very acute awareness of your body, reading it for clues about your exact day of ovulation and abstaining from sex (or using a condom ) on these days. 

Clues include:

• Basal Body Temperature:  Buy a basal thermometer (it has an extra decimal, measuring to the hundredths) and take your temperature every morning, very first thing, before you even get out of bed.  Chart your temperature on graph paper, and when you see it jump about 0.4F (~0.2C) then you know that you ovulated.  Tough luck if you've had sex in the last three days!  Sperm can live that long inside of you.  Temperature alone does not warn you of impending ovulation, but it can help you get to know your cycle better, and that is a good deal more helpful than counting days on the calendar. 

• Cervical Mucous: Inspect your vaginal discharge every day.  Keep an eye out for the changes.  When it seems to get slippery or mucousy, stop having sex or use a condom.  When it appears like egg whites, forming goey strands between your finger and thumb as you stretch it apart, then that's your ovulation.  Abstain for a few more days.  This will likely add up to about a week of condoms or abstention. 

If you choose to practice this method of birth control, I HIGHLY recommend that you get a coach or attend a class to help you learn how to do it well.  When done correctly, this method is about as effective at preventing pregnancy as condoms, but without help, you might end up staring at your discharge every day not quite knowing what to make of it and getting pregnant for lack of support.  There are educational seminars on this method almost anywhere there is a Catholic church.  Seek one out and drop in, no matter what your religion. The church certainly has its dogmatic motives to push this method of birth control.  They have funded most of the research that has gone into it and they run most of the education that there is about it.  My gut reaction to that fact was suspicion of the results, but then I thought about it further and realized that lots of stats on the pill are presented by drug companies, and stats on condoms are presented by durex, so the church probably isn't that different.  If this is a method you want to use, then I recommend using their resources.

Now, none of this is as effective at preventing pregnancy as hormonal methods or IUDs.  Condoms and sympto-thermal method have ~3% failure rate per year (perfect use).  The pill and IUDs have ~0.1% failure rate per year (perfect use).  If you really, really want to cover your bases, you want to prevent ovulation or implantation, and that means hormones and IUDs.  Being allergic to nickel, I agree that metal is out as a method of BC.  You'd have to go for an IUD that is made of plastic, and these contain very low levels of hormones.  Consider that you were once on the shot, which is the biggest wallop of hormone on the market.  It's a huge dose, delivered in one go every few months.  It is a method of birth control that has many side effects for many people because of this dose and drug delivery method.  If you didn't get side effects from that, you would very likely be absolutely fine on a low-dose pill (less hormone) or on a hormonal IUD (minuscule amounts of hormone).  These would be the best at preventing pregnancy, but if you don't want the hormone, then you don't want the hormone.

Hormonal contraceptives are a very effective method of birth control.  IUDs are also very effective and are dummy-proof.  Condoms are a good method of birth control and the only one that protects against STI transmission.  Sympto-thermal is also, in my opinion, a good method of birth control, but one that takes a lot more planning and self-control than simply taking a pill every day or keeping the cupboard stocked with condoms.  Calendar method?  It's definitely better than nothing, but I wouldn't rely on it.

I believe that the sympto-thermal method of birth control is a really, really good thing to practice for any ovulating woman, but that it's even better if you're not using it exclusively.  More knowledge about your cycle can only help you.  So go ahead and learn about it!  Track that temperature.  Inspect that cervical mucous.  Learn as much as you can about your fertility.  On top of it all, I recommend to keep using those condoms.  Two methods are better than one!  And if your condom fails you?  At least you'll have a good idea of your risks and will know whether or not to run out for the Plan B.

Good luck with it!  I hope that it works out well for you.

Additional Reading:

I talked to three women today who used the sympto-thermal method of birth control, two to avoid pregnancy, and all three to get pregnant when they felt ready.  The all recommend a book: Taking Charge of Your Fertility. 

Comments

[KateC]

Important additions from a friend of mine in nursing (Thanks, K!):

There are 2 things I would add, as some one who now has in depth contraceptive training for school.

1. The symptothermal method requires 6 months of self observation to be effective. The months are needed to look at the average of your period length and that is where you get the number of days you will need to be abstinent- subtract 18 days for your shortest period and 11 days from your longest period. So if your longest period was 33 days and your shortest period was 26 days you would need to be abstinent from day 8 to day 22. And part of the "safe" time is during menses which is something to consider as well if she or her partner doesn't like having sex during menses. She also has to have a compliant partner. With that said I am a big proponent of the symptothermal method because a woman has the opportunity to really understand her cycle and the hormonal changes that occur. It will come in handy if she every does what to get pregnant too. Like you said- if you are going to use this method you need extensive training and motivation.

2. Oral contraceptives actually only have an 8% effectiveness rate when looking at the "actual use" percentages. 0.3% effective for perfect use like you said.
I wrote more than I was planning, but I LOVE maternal/neonatal health and think it's so great you're getting information out to your readers.