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.
‘[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.