Investigating NFP: The Great Embryo Killer? (Part I)

"What is the expectation of embryonic death for rhythm method users? Our first assumption was that only half of the embryos are viable. I take it that this value holds for populations using no contraception and not distinguishing between HF and non-HF periods (or using contraceptive techniques that do not distinguish between HF and non-HF periods)."

Assuming the claim that about 50% of all embryos are viable, this much makes sense.

"What is not known is what proportion of embryos are conceived during the HF period as opposed to outside the HF period. Since it is reasonable to assume that only a minority of embryos are conceived outside the HF period, let us make a broad estimate that between 1/10 and 1/3 are so conceived."

Technically speaking, conception can only take place when both an ovum and a sperm are present. It cannot take place prior to ovulation. What he means by this sloppy shorthand is that either sperm deposited during the pre-HF period (possibly as old as 5 days) may fertilize an ovum or a sperm could fertilize and "old" ovum during the post-HF period.

"Then, by our third assumption—that is, that the chance of the viability is twice as high for an embryo conceived during the HF period as for an embryo conceived outside of the HF period, we can calculate that the chance of viability outside the HF period ranges roughly from one in four to one in three."

"[Footnote i.] By the probability calculus, the probability of viability (p) equals the conditional probability of viability given that the conception occurred outside the HF period (q) times the probability that the conception occurred outside the HF period (r) plus the conditional probability of viability given that the conception occurred during the HF period (2q) times the probability that the conception occurred during the HF period (1-r). Hence, p = qr + 2q(1-r). We set p = 1/2 by assumption one and let r ∈ [1/10, 1/3]. Hence q ∈ [10/38, 3/10] ≈ [1/4, 1/3].

Now we must ask if Bovens third assumption, about HF and fringe conceptions having different embryo survival rates, is right. According to this article ("Timing of conception and the risk of spontaneous abortion among pregnancies occurring during the use of natural family planning", AM J OBSTET GYNECOL 1995; 172:1567-72.) in the American Journal of Obstetric Gynecology, it may not be. (Fedora Tip: UnSpace) According to MedlinePlus, "It is estimated that up to 50% of all fertilized eggs die and are lost (aborted) spontaneously, usually before the woman knows she is pregnant. Among known pregnancies, the rate of spontaneous abortion is approximately 10% and usually occurs between the 7th and 12th weeks of pregnancy." So this study does not directly address Bovens’ claims. However, Bovens cites no research whatsoever.

The study found that "the spontaneous abortion rate was similar for 361 optimally timed conceptions (9.1%) and 507 non-optimally timed conceptions (10.9%)" and concluded, "These differences were not statistically significant (relative risk l.19, 95% confidence interval 0.79 to 1.80)." Thus until evidence supports the hypothesis that there is a statistically signficant difference, we can treat the relative risk as being effectively 1.0. However, women with a history of preganacy loss were more than twice as likely to miscarry when then conceived at non-optimal times, i.e. at the fringes of their fertile periods. Thankfully, as I have already mentioned, this unfortunate occurrence can be reduced in likelihood by modifying NFP’s rules. According to the study, if conception was optimally timed, women prone to spontanteous abortions had them about as often as women without such a history. It is reasonable to hypothesize that if intercourse timing does not, for most women, affect the rate that known pregnancies spontaneously abort, then it does not affect the rate of "silent" spontaneous abortions. This is called a testable hypothesis, Mr. Bovens, and it is the cornerstone of the scientific method. If anyone can point to research relating intercourse timing and pre-implantation embryo death, I’d much abliged.

The next section of Bovens’ article explains the mathematical consequences of Bovens’ assumptions. Since the most important assumption, that NFP leads to more spontaneous abortions than other methods of birth control (or even randomly-timed intercourse), has no support, I’ll skip that part. I will, however, point out that Bovens misrepresented some statements by Randy Alcorn.

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About Funky Dung

Who is Funky Dung? 29-year-old grad student in Intelligent Systems (A.I.) at the University of Pittsburgh. I consider myself to be politically moderate and independent and somewhere between a traditional and neo-traditional Catholic. I was raised Lutheran, spent a number of years as an agnostic, and joined the Catholic Church at the 2000 Easter Vigil. Why Funky Dung? I haven't been asked this question nearly as many times as you or I might expect. Funky Dung is a reference to an obscure Pink Floyd song. On the album Atom Heart Mother, there is a track called Atom Heart Mother Suite. It's broken up into movements, like a symphony, and one of the movements is called Funky Dung. I picked that nickname a long time ago (while I was still in high school I think), shortly after getting an internet connection for the first time. To me it means "cool/neat/groovy/spiffy stuff/crap/shiznit", as in "That's some cool stuff, dude!" Whence Ales Rarus? I used to enjoy making people guess what this means, but I've decided to relent and make it known to all. Ales Rarus is a Latin play on words. "Avis rarus" means "a rare bird" and carries similar meaning to "an odd fellow". "Ales" is another Latin word for bird that carries connotations of omens, signs of the times, and/or augery. If you want to get technical, both "avis" and "ales" are feminine (requiring "rara", but they can be made masculine in poetry (which tends to breaks lots of rules). I decided I'd rather have a masculine name in Latin. ;) Yeah, I'm a nerd. So what? :-P Wherefore blog? It is my intention to "teach in order to lead others to faith" by being always "on the lookout for occasions of announcing Christ by word, either to unbelievers . . . or to the faithful" through the "use of the communications media". I also act knowing that I "have the right and even at times a duty to manifest to the sacred pastors [my] opinion on matters which pertain to the good of the Church, and [I] have a right to make [my] opinion known to the other Christian faithful, with due regard to the integrity of faith and morals and reverence toward [my and their] pastors, and with consideration for the common good and the dignity of persons." (adapted from CCC 904-907) Statement of Faith I have been baptized and confirmed in the name of the Father, Son and Holy Spirit. I, therefore, renounce Satan; I renounce all his works; I renounce all his allurements. I hold and profess all that is contained in the Apostles' Creed, the Niceno- Constantinopolitan Creed, and the Athanasian Creed. Having been buried with Christ unto death and raised up with him unto a new life, I promise to live no longer for myself or for that world which is the enemy of God but for him who died for me and rose again, serving God, my heavenly Father, faithfully and unto death in the holy Catholic Church. I am obedient to the Magisterium of the Catholic Church. That is, I promote and defend authentic Catholic Teaching and Faith in union with Christ and His Church and in union with the Holy Father, the Bishop of Rome, the Successor of St. Peter. Thanks be unto Thee, O my God, for all Thy infinite goodness, and, especially, for the love Thou hast shown unto me at my Confirmation. I Give Thee thanks that Thou didst then send down Thy Holy Spirit unto my soul with all His gifts and graces. May He take full possession of me for ever. May His divine unction cause my face to shine. May His heavenly wisdom reign in my heart. May His understanding enlighten my darkness. May His counsel guide me. May His knowledge instruct me. May His piety make me fervent. May His divine fear keep me from all evil. Drive from my soul, O Lord, all that may defile it. Give me grace to be Thy faithful soldier, that having fought the good fight of faith, I may be brought to the crown of everlasting life, through the merits of Thy dearly beloved Son, our Savior, Jesus Christ. Amen. Behind the Curtain: an Interview With Funky Dung (Thursday, March 03, 2005) I try to avoid most memes that make their way 'round the blogosphere (We really do need a better name, don't we?), but some are worth participating in. Take for instance the "interview game" that's the talk o' the 'sphere. I think it's a great way to get to know the people in neighborhood. Who are the people in your neighborhood? In your neighborhod? In your neigh-bor-hoo-ood...*smack* Sorry, Sesame Street flashback. Anyhow, I saw Jeff "Curt Jester" Miller's answers and figured since he's a regular reader of mine he'd be a good interviewer. Without further ado, here are my answers to his questions. 1. Being that your pseudonym Funky Dung was chosen from a Pink Floyd track on Atom Heart Mother, what is you favorite Pink Floyd song and why? Wow. That's a tuffy. It's hard to pick out a single favorite. Pink Floyd isn't really a band known for singles. They mostly did album rock and my appreciation of them is mostly of a gestalt nature. If I had to pick one, though, it'd be "Comfortably Numb". I get chills up my spine every time I hear it and if it's been long enough since the last time, I get midty-eyed. I really don't know why. That's a rather unsatisfying answer for an interview, so here are the lyrics to a Rush song. It's not their best piece of music, but the lyrics describe me pretty well.

New World Man He's a rebel and a runner He's a signal turning green He's a restless young romantic Wants to run the big machine He's got a problem with his poisons But you know he'll find a cure He's cleaning up his systems To keep his nature pure Learning to match the beat of the old world man Learning to catch the heat of the third world man He's got to make his own mistakes And learn to mend the mess he makes He's old enough to know what's right But young enough not to choose it He's noble enough to win the world But weak enough to lose it --- He's a new world man... He's a radio receiver Tuned to factories and farms He's a writer and arranger And a young boy bearing arms He's got a problem with his power With weapons on patrol He's got to walk a fine line And keep his self-control Trying to save the day for the old world man Trying to pave the way for the third world man He's not concerned with yesterday He knows constant change is here today He's noble enough to know what's right But weak enough not to choose it He's wise enough to win the world But fool enough to lose it --- He's a new world man...
2. What do you consider your most important turning point from agnosticism to the Catholic Church. At some point in '99, I started attending RCIA at the Pittsburgh Oratory. I mostly went to ask a lot of obnoxious Protestant questions. Or at least that's what I told myself. I think deep down I wanted desperately to have faith again. At that point I think I'd decided that if any variety of Christianity had the Truth, the Catholic Church did. Protestantism's wholesale rejection of 1500 years of tradition didn't sit well with me, even as a former Lutheran. During class one week, Sister Bernadette Young (who runs the program) passed out thin booklet called "Handbook for Today's Catholic". One paragraph in that book spoke to me and I nearly cried as I read it.
"A person who is seeking deeper insight into reality may sometimes have doubts, even about God himself. Such doubts do not necessarily indicate lack of faith. They may be just the opposite - a sign of growing faith. Faith is alive and dynamic. It seeks, through grace, to penetrate into the very mystery of God. If a particular doctrine of faith no longer 'makes sense' to a person, the person should go right on seeking. To know what a doctrine says is one thing. To gain insight into its meaning through the gift of understanding is something else. When in doubt, 'Seek and you will find.' The person who seeks y reading, discussing, thinking, or praying eventually sees the light. The person who talks to God even when God is 'not there' is alive with faith."
At the end of class I told Sr. Bernadette that I wanted to enter the Church at the next Easter vigil. 3. If you were a tree what kind of, oh sorry about that .. what is the PODest thing you have ever done? I set up WikiIndex, a clearinghouse for reviews of theological books, good, bad, and ugly. It has a long way to go, but it'll be cool when it's finished. :) 4. What is your favorite quote from Venerable John Henry Newman? "Ten thousand difficulties do not make one doubt." 5. If you could ban one hymn from existence, what would it be? That's a tough one. As a member of the Society for a Moratorium on the Music of Marty Haugen and David Haas, there are obviously a lot of songs that grate on my nerves. If I had to pick one, though, I'd probably pick "Sing of the Lord's Goodness" by Ernie Sands.

15 thoughts on “Investigating NFP: The Great Embryo Killer? (Part I)

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  4. Tom Smith

    Actually, this guy probably isn’t a real philosopher. He didn’t talk about an “embryo qua embryo,” or describe his argument as “mutatis mutandis, standing,” or discuss how the argument is “apodictic, a fortiori.” He didn’t talk about how the “entelechy-enabling abient behavior, ex hypothesi,” is “formally rooted in essence.” Clearly, not only is this man not a philosopher, but he is a poor arguer, inter alia. Cetris paribus, this guy sucks.

    Sorry, I couldn’t resist an opportunity to bash philoso-babble.

  5. Pingback: Ales Rarus - A Rare Bird, A Strange Duck, One Funky Blog » Investigating NFP: The Great Embryo Killer? (Part II)

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  12. HEWHitney

    The discussion is below anyone’s expectation of reasonable articulation.

    Bovens is a respected medical ethicist. The criticisms are (at least not so identified) by untrained individuals, obviously limited to Catholic definitions.

  13. Funky Dung Post author

    “The discussion is below anyone’s expectation of reasonable articulation.”

    But a critical comment offering no substance whatsoever meets those expectations?

    “Bovens is a respected medical ethicist.”

    Since when are appeals to alleged reputation adequate substitutes for rational debate in science, medicine, or philosophy?

    “The criticisms are (at least not so identified) by untrained individuals, obviously limited to Catholic definitions.”

    Untrained? Perhaps. I’m certainly no expert. However, attacking my lack of formal training does nothing to refute my arguments. I have attempted to refute Bovens in a rational and methodical manner. Either treat me likewise or bugger off. Drive-by “You’re wrong” comments unsupported by at least an attempt at sound reasoning are a waste of everyone’s time and will not be tolerated a second time.

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