Mangling, Mishandling, and Misrepresentation of Science in the Plan B Debate (Part I)

In an effort to inform people that the Journal of Medical Ethics needs greater scrutiny in the peer review process, I’ve been scouring the net for mentions of "rhythm method", "Plan B", "embryo death", "Bovens", and related topics. In the process, I have come across some startling bad statements regarding the scientific study of fertility – on both sides of the political spectrum. Let’s start with some MSM headlines related to Bovens’ article about an alleged relationship between the "rhythm method" and embryo death.

Rhythm method kills more embryos than condom use
Controversial rhythm method study revealed
Rhythm method linked to massive embryonic death
How Vatican roulette kills embryos
‘Rhythm’ method a killer of embryos

Notice a trend in these headlines? They all assume two things: that Bovens published the results of a scientific study and that study clearly implicated the rhythm method with embryo deaths. IT’S NOT A STUDY! It’s a sloppy polemical essay. JME should be ashamed for publishing it.

In the wake of this publication, there have been numerous examples of folks showing a poor understanding of fertility and an unwillingness to be corrected. I am certainly no expert in fertility, but I have attempted to do my homework. If you believe my following observations are incorrect or misleading in any way, do not hesitate to let me know.

In the liberal sector of the blogosphere, I’ve seen several attempts to say that Plan B is no more abortifacient than breastfeeding. This may be the case, but it’s not for the reasons typically sited. Here’s a representative example.

"Of course, proponents of NFP also favor "ecological breastfeeding, God’s own way of spacing babies." Which prevents conception by raising progesterone levels, exactly like Plan B."

‘[Former FDA official Susan] Wood compares Plan B to breastfeeding, which also changes a woman’s hormonal balance. ‘If you are breastfeeding, you are less likely to get pregnant,’ she says, and that’s because you have this elevated progesterone level in your body, which is exactly what happens when you have Plan B emergency contraception."

"But I don’t think I’ve heard anyone on the religious right object to a ‘breastfeeding abortion.’"

I’ve found no scientific backing for the claim that breastfeeding elevated progesterone levels. In fact, I’ve found just the opposite.

"Breast-feeding is associated with high plasma concentrations of prolactin, at least at the onset of lactation, the levels correlating to some extent with the number of suckling episodes. The prolactin response to suckling declines with time post-partum, but if suckling frequency is maintained at a high level basal levels may well remain above normal for 18 months or more."

"Blood levels of follicle-stimulating hormone IFSH) are necessary for ovarian follicular growth and development, and quickly return to normal menstrual cycle levels within a week or two post-partum. At no stage during lactational amenorrhoea do FSH levels appear to be inadequate for ovarian function. Pituitary levels of luteinizing hormone (LH) are very low immediately postpartum, but by 15 to 20 days blood levels have increased significantly and remain throughout lactation on the lower side of normal."

"During lactational amenorrhoea in fully breast-feeding women, the response of LH to GnRH stimulation is diminished, while the FSH response is normal. In the same situation, women fail to show a positive feed-back response, with an increase in LH and FSH to exogenously administered oestrogen, whereas they show an enhanced negative feed-back effect with prolonged suppression of LH levels in contrast to normally cyclic women. In lactational amenorrhoea, ovarian oestrogen and progesterone secretion is below normal, and is equivalent to that seen in post-menopausal women in spite of normal levels of FSH." [Emphasis mine]

"Complete weaning results in an immediate drop in the blood levels of prolactin and an increase in blood levels of LH and oestradiol, indicating a prompt resumption of ovarian activity. Actual ovulation usually occurs within 14 to 30 days. These results suggest that a maintained suckling stimulus, and the associated hyperprolactinaemia, suppress LH but not FSH post-partum and lead to both a failure of ovarian follicular development and lactational amenorrhoea. There is also some information that if ovulation does occur it results in a deficient corpus luteum function."

In other words, breastfeeding raises prolactin levels and lowers progesterone levels. Furthermore, increased prolactin levels only prevent ovulation and do not affect the lining of the uterus. Similar explanations can be found here and here. That’s just the first part of the claim that Plan B is like breastfeeding, though. The second part says that if they act by elevating the same hormone levels, they control birth similarly. Since Plan B is believed to sometimes interefere with implantation, and breastfeeding is mistakenly believed to elevate the same hormones, Plan B is allegedly no more or less abortifacient than breastfeeding. Obviously, if the first part fails, so does the second part. Don’t jump to any conclusions about that, though. Just because breastfeeding isn’t abortifacient, doesn’t mean Plan B is. In fact, that leads me to how the conservative sector of the blogosphere abuses or is ignorant of science.

Read Part II of "Mangling, Mishandling, and Misrepresentation of Science in the Plan B Debate"

Comments 4

  1. Richard wrote:

    I too was surprised at the statements about progesterone levels, fertility and breasfeeding, since my understanding is that progesterone drops rapidly following birth. But here is a scientific paper that shows a relationship between postnatal progesterone levels and the supression of menstruation in breastfeeding women. “The association of progesterone, infant formula use and pacifier use with the return of menstruation in breastfeeding women: a prospective cohort study” Ingram et al. European Journal of Obstetrics & Gynecology and Reproductive Biology Volume 114, Issue 2 , 15 June 2004, Pages 197-202.
    To quote from the paper:
    “Our study shows that for this group of 85 breastfeeding mothers, the return of menstruation is associated with several factors including the introduction of formula
    feeds, the early use of pacifiers (both of hich affect the frequency of breastfeeds)
    and lower postpartum progesterone levels.”

    And elsewhere:

    “Again, postnatal progesterone was the only hormone associated with return of menstruation, the significant negative coefficient indicating that higher
    concentrations were associated with less chance of the return of menses and hence a
    longer period of amenorrhoea (P=0.012).”

    Of course, correlation does not mean causality, as suggested by the analogy to Plan B. Still, scientific articles like this could be the basis of the proposal that breasfeeding mimics Plan B in some way.

    Posted 09 Jun 2006 at 7:42 am
  2. Stuff wrote:

    Regarding breastfeeding specifically, the study cited by Richard seems to be in complete harmony with the conclusions in the post. The correlations that I personally have seen between breastfeeding and progesterone have suggested that ecological breastfeeding is responsible for *higher* levels of progesterone – high enough to cause amenorrhea. Not that I’ve read the study, but it seems to be saying that progesterone only returns during breastfeeding when an infant begins to be weaned (through use of formula, pacifiers, etc.). The whole idea of ecological breastfeeding is that the infant if fed AND comforted (“pacified”) *only* at the breast – meaning a mother will be nursing her child anywhere from every 30 minutes to every 3-4 hours. Breastfeeding works by means of a sort of supply/demand feedback mechanism – the more you breastfeed, the more your body is stimulated to produce the hormone prolactin, responsible for milk production (and suppressed ovulation, as cited in the post). The less the infant demands (because of receiving formula, pacifiers, solid food, etc.), the less prolactin and milk. It seems that the only time progesterone enters the picture is when weaning begins, so it would seem to me that it is not breastfeeding but lack thereof that is responsible for any progesterone-related anything!

    Posted 09 Jun 2006 at 5:51 pm
  3. Beverly Nuckols, MD wrote:

    Again, thank you for addressing this subject. The JME appears to be a collection of papers from undergraduates with an agenda. (Did you see the one about the cultures of the “Ovoids”?

    Posted 14 Jun 2006 at 6:42 pm
  4. Curiously_Confused wrote:

    Wait, I’m confused. Prolactin lowers progesterone levels? I thought it lower estrogen levels. So, since it lowers progesterone levels that (as I understand it) are necessary for implantation, wouldn’t that suggest that breastfeeding is actually an abortifacient? On the other hand, boosting one’s progesterone levels while lactating is considered acceptable. If prolactin opposes progesterone, how could these treatments be compatible with breastfeeding then? And what about the deficient corpus luteum function that the study says can be brought on by lactation? Wouldn’t that be considered an abortifacient effect? Seems to me like the case against breastfeeding is stronger than the case against the pill. Very confusing. I mean, try to imagine the, Nation Pro-life Anti-Breastfeeding Association. As nice as it is to be right, in this particular instance, it’d be nice if someone could prove me wrong.

    Posted 06 Feb 2008 at 6:29 pm

Trackbacks & Pingbacks 5

  1. From Nerd Family on 14 Jun 2006 at 4:40 pm

    universalism is openly accepted among those who belong to, and especially those employed by, various Christian institutions in Underground Universalism. Let us move from church politics to society and politics. Ales Rarus has an interesting article,Mangling, Mishandling, and Misrepresentation of Science in the Plan B Debate. Looking to Hollywood, Nehring tells us about a Christian film, Facing The Giants, that has been given a higher film rating because it was too “proselytizing” in JESUS LOVES YOU BUT HOLLYWOOD THINKS YOU’RE A JERK

  2. From CowPi on 13 Jun 2006 at 6:50 am

    Catholic Carnival #83…

    As we mingle through this week’s carnival, our focus will move from the outward to the inward. When statesmen forsake their own private conscience for the sake of their public duties, they lead their country by a short route to……

  3. From Ales Rarus - A Rare Bird, A Strange Duck, One Funky Blog » Mangling, Mishandling, and Misrepresentation of Science in the Plan B Debate (Part II) on 14 Jun 2006 at 1:50 pm

    […] In all my searching, I have found no studies that support the notion that Plan B acts as an abortifacient. […]

  4. From Investigating NFP: The Great Embryo Killer? (Update) | Science on 24 Aug 2006 at 10:37 am

    […] Investigating NFP: The Great Embryo Killer? (Update) By Funky Dung Some updates regarding Bovens' bunkum:The NY Times printed a reasonably fair article about the paper – a welcome contrast to many articles that proceded it .Bovens has responded to his critics. I'd intended to fisk his inadequate responses, but others have already done that far better than I ever could. […]

  5. From Generations for Life » Blog Archive » Does NFP Lead to “Massive Embryonic Death”? on 03 May 2007 at 10:16 am

    […] I think that’s more a matter of covering themselves than reporting the results of scientific studies. Thus far, the pharmacological inserts are the only places I’ve seen any mention of implantation being affected. […]

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