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July 09, 2013


A scientist tests the science behind natural family planning:

Little known and rarely utilized is the single method of birth control supported by the Catholic Church. Righteously termed "natural family planning," the method limits sexual intercourse to women's naturally infertile periods, such as certain portions of the menstrual cycle, menopause, or during pregnancy. Pope Paul VI's rationale for approving natural family planning versus other methods was that it "uses a faculty given by nature whereas contraception impedes nature."

To me, that seems a dogmatic and unscientific argument. So I assumed that the method itself would be similarly lacking in evidence. But to my surprise, I was wrong.

As it's typically used, natural family planning is about as effective as the female condom -- between 75 and 80% successful at preventing pregnancy over the course of a year. But when perfectly used, it can be 95% effective or higher. A large study conducted in 2007 found that the "symptothermal" method of natural family planning, in which the female user tracks both her body temperature and cervical secretions to gauge her fertility, is 99.6% effective when properly adopted, roughly the same as a copper intrauterine device.

Sorry - we couldn't resist the title.

Posted by Cassandra at July 9, 2013 08:11 AM

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And here I thought it was because of the picture in the article....

Posted by: Evil Twin at July 9, 2013 03:06 PM

I did not even see the picture :p

Posted by: Cass at July 9, 2013 06:18 PM

The fiance and I took an NFP class over the winter. You can't completely depend on the rules (as guidelines for fertility between the end of menstruation and ovulation) until you have at least 6 months of history for charting your temps and other observations. But, I think it will be the right thing for us. I've never been (and don't want to be) on the pill or any other form of contraception. It requires a partnership (and communication!) between the couple, precisely because you can't have sex any ol' time you want, if you are trying to avoid pregnancy. As "birth control", it's just the flip side of what you need to know if you are *trying* to get pregnant. Funny, I don't recall every hearing about non-natural (pills and condoms and such) means of "birth control" when I took sex ed, outside of just "abstinence"... We are getting married in the Catholic Church, so an introductory class about what NFP is (not how to actually practice it) was my first real introduction to it. It's not the old "rhythm method" from back in the day that was not as effective (you apparently just counted days on the calendar, based on you certain assumptions about a woman's cycle).

Doing this has made me more aware of things, including the fact that when we are ready, it is likely going to be more difficult to get pregnant, we do not have an unlimited period of time to try to do so, and we really don't know how much longer we'll have to even try. Just for that knowledge (given my age), paying to take the actual NFP course was worth it...

Posted by: Miss Ladybug at July 9, 2013 07:35 PM

Wow, both irony and personal connection.

Early in our marriage my wife was hugely anxious to have a child. Didn't happen right away, so she quickly sought medical help. After the 'normal' preliminaries, the Gyn gave us a sensitive thermometer, and prescribed daily monitoring of hopeful mom's temp, very carefully done upon awakening and before getting out of bed.

> A kinda small, but distinct rise in body temp, is characteristic when a woman ovulates . . . make sure to hit that 'window in time,' and much more often than not she will 'catch.'

Unfortunately the first pregnancy ended in a miscarriage, which was very tough on her emotionally. But the 'system' works' for most couples, and our son followed soon after. He was born while I was underway on patrol.

Best Regards,

Posted by: CAPT Mike at July 9, 2013 11:42 PM