I was thinking about this recently in terms of high loss of blood during childbirth causing pituitary infarction or Sheehan’s Syndrome. What I’ve read about this indicates this is a rare occurrence. However, I’ve talked to various women who had traumatic high blood loss labours, and despite pumping to stimulate supply, often for weeks, never produced a drop of milk. According to the article this certainly is a major symptom of minor Sheehan’s Syndrome. Yet, absolutely none of the women I’ve talked to were ever told that blood loss could cause breastfeeding issues. None of them had blood work, MRIs to examine the pituitary, nothing. All were more or less left to their own devices when lactation failed. Which is something that irritates me to no end. Just because there is something that can feed a baby shouldn’t mean that investigation into why the normal method isn’t working is unnecessary. But that’s not the point of this article. The point here is that, how rare are things really when no diagnoses or investigation is done? Is the rare diagnosis a historical artifact (I did find a paper on incidence rates from 1960-when there were significantly less c-sections or early inductions of labour)? I know research papers are written examining a portion of a population who volunteered, but surely these things vary by hospital, genetic makeup of the population and other factors?
This article states that mammary hypoplasia (insufficient glandular tissue) is about 0.1% of the population. So 1 out of 1000 women. I’m not sure if I’m happy with that statistic, but let’s just take that into consideration. That is similar to the number of babies born with Down’s Syndrome. That doesn’t seem so rare to me. Unusual perhaps. But since the only way this condition is manifesting is appearance of the breasts and lack of milk (two relatively hidden things) I’m sure the diagnosis rate is much lower. I have no idea if this might be partly my issue because no one checked. How many other women have similar stories? I know the ‘oh I didn’t make enough milk’ is often a screen for being uneducated about what breastfeeding –and babies–can be like, not to mention a bugbear of the ‘oh not enough milk is sooo rare’ crowd, but how can we really know when so little investigation is done? What about some semi-realistic numbers?
So what about PCOS (Polycystic Ovarian Syndrome)? Reported rates of this vary wildly. I’ve read 10% of women have it, but 50% show signs of it in the US. Yikes. Let’s stick with that 10% figure. So of that 10% a survey of PCOS sufferers indicated a 25-30% have milk supply issues resulting from either poor breast development in puberty or in pregnancy. So there’s another potential 2-3%. How does that mesh with the breast hypoplasia figures? It would seem that these would be in addition to, or rather, the previous figures for hypoplasia might be hypoplasia of unexplained origin, e.g. not obviously PCOS related.
Now, another cause of lactation issues, thyroid issues has a range of percentages and causes. Let’s pick them apart. Hashimoto’s (autoimmune hypothyroid) is in the range of 1 to 1.5 per 1000 with around 20% of sufferers experiencing lactation issues. Graves Disease (hyperthyroid) effects up to 2% of women. That’s 2:100. Postpartum Thyroidosis effects 5 to 10% of women. Onset is usually around eight weeks to four months postpartum and with not much information on the effects on lactation it anyone’s guess as to how many women. Now, information on the effects of non-autoimmune thyroid issues on lactation is very sparse here so we’re certainly wandering into under-diagnosed territory. Overall thyroid issues are more common, but there is little information on their effect on lactation. This article certainly seems to indicate that lowered milk production is a possible side effect. How many though? What if it was something similar to 20% of thyroid issue sufferers can expect milk production or release issues, like expected for those suffering Hashimoto’s? That would put the numbers at a possible 1%. Of the potentially 5% suffering from thyroid problems, 20% with lactation issues. This is just a hypothesis of course, but it seems a reasonable assumption at first look.