The past few weeks have seen big news for vaccines. A bill related to vaccine exemptions was signed into law, a court ruled against a parent’s refusal to vaccinate and a recent study points out the value of vaccinating a household — especially mom — to protect a young infant from pertussis (whooping cough).
The latest news is that Governor Jerry Brown in California signed a bill last Sunday that had been sitting on his desk since September 6 and was the target of a number of rallies by parents who didn’t want to see it pass. Among those fighting the bill was Dr. Bob Sears, who says he walks a middle ground with vaccine policy but in reality tends to flirt with those who fear vaccines and rely on misinformation. Although some parents claimed the bill took away their right to choose whether their children get vaccinated, it actually just ensures they get good medical information before they make that choice.
Photo by Dave Gostisha at sxc.hu.
The bill-now-law, AB 2109, proposed by a pediatrician, requires parents to get a statement signed by a health care practitioner that the parents/guardians have received accurate, evidence-based information about the risks and benefits of vaccines before they can use a personal belief exemption to prevent their children from being vaccinated. This law is a tremendous triumph both for informed consent in medical decisions and for the public health of children in California, which saw a considerable outbreak of pertussis (whooping cough) in 2010. Washington state passed a similar law last year and saw 25 percent drop in exemptions filed. Other states are considering similar laws in a nationwide overall shift toward strengthening exemption requirements.
Why are these laws so important? In short, they kill two birds with one stone: They make it more difficult for parents to casually opt out of vaccines on philosophical grounds (as opposed to religious or medical reasons), and they require parents who want to opt out to at least hear out a pediatrician on accurate information about the actual risks (which do exist) and benefits (there are so many) of immunizations. Parents who are determined not to vaccinate their children can still refuse, but many parents who might have signed those forms out of convenience — it can be easier to sign than to get to the doctor’s office for the shot — will now at least hear the impact a decision not to vaccinate can have on the community. (Hopefully, they go to a health care practitioner other than Dr. Sears, whose stances have gradually been moving further and further toward unscientific and misinformation of those who oppose vaccines.)
It’s also particularly notable that California and Washington are the most recent states to tighten opt-out procedures for parents because they are home to some of the more recent pertussis outbreaks. More on that in a moment.
First, a bit of background on vaccine exemptions: Only 20 states have personal belief exemptions, and until last year, eight of these simply require nothing more than a parent signature. Now that number is down to six. (Other types of requirements for philosophical exemptions include writing out your reasons for exemption, requiring the forms to be notarized, requiring education on the risks/benefits, direct involvement from the state or local health department or renewals.)
All states have medical exemptions for patients who have auto-immune disorders, have proof that their bodies do not respond to immunization, have documented allergic reactions or have other circumstances which make it too risky for them to be immunized. In fact, these are the very people that the rest of the population protects through herd immunity when vaccination rates are up where they should be. All but two states have religious exemptions (Mississippi and West Virginia are the exceptions).
And that brings us to some less covered but still significant news about one state’s ruling on a particular case involving religious exemption. Last week, the U.S. district court in Ohio ruled that one woman’s claim of religious objection was insufficient for her children to be exempted from being vaccinated. Read the whole story here. To be fair, this is a complex case involving far more than vaccines; the mother is clearly neglectful and the overall situation is pretty crappy. However, the fact that the court found “the mere assertion of a religious belief … does not automatically trigger First Amendment protections,” and that “it has long been recognized that local authorities may constitutionally mandate vaccinations” is significant in a state that offers both religious and personal belief exemptions.
The constitutionality of religious exemptions is dubious as well. At the very least, however, anyone seeking any exemption should certainly to see a doctor first to be sure they have accurate information and not simply what they have seen online or heard at the playground. Those who absolutely will not vaccinate in states without exemptions may also opt to home school or send their children to private schools that don’t have requirements. But considering the increasing rates of measles and the increasing epidemics of pertussis, the need for high vaccination coverage in communities is more important than ever.
It is true that the pertussis vaccine is not as effective as the old one used to be, something I wrote about a few weeks ago. It’s also true that pertussis peaks every five years or so, but even taking into account the peaks, the overall rate of cases has been steadily on the move upward. Dr. Offit, the chief of the Division of Infectious Disease at Children’s Hospital of Philadelphia and a very vocal advocate of vaccines, said he believes that parents’ refusals to vaccinate are playing their own small part in the increase.
“The major contributor is waning immunity. The minor contributor is the choice not vaccinate,” he said. He noted that there are researchers working on the problem, as this Nature article notes (paywall), including attempts to make a better vaccine with more adjuvants, the additives that enhance the body’s immune response to a vaccine. While vaccinated children and adults have been high among the numbers of those getting whooping cough, getting the vaccine remains among the best ways to reduce your risk of contracting it — or of having less rough of a time with it if you do get it. Dr. Offit also pointed out that pregnant women in particular should be sure they get their booster.
Which brings us to the study published last week that relates to the most important reason to get vaccinated, at least from the perspective of preventing deaths — to protect the babies who are too young for the vaccine but most likely to contract it and die from it.
The study, published in the journal Epidemiology last week, looked at how frequently pertussis was transmitted to others within the same household and how effective “cocooning” is. Cocooning is vaccinating all the household members who can get the vaccine for the purpose of protecting young babies who can’t yet be vaccinated for the disease.
They found that transmission rates within the home are high, especially for mothers passing the illness on to their children. Therefore, making sure all pregnant women are vaccinated before their baby arrives would, according to their calculations, cut the risk in half that a baby would contract pertussis. The evidence for sibling vaccination, though weaker, still points to the value of overall cocooning: “Vaccination of siblings is less effective in preventing transmission within the household, but may be as effective overall because siblings more often introduce an infection in the household.”
Indeed, this year, siblings’ bringing home the disease appears more likely than ever in the states experiencing big outbreaks this year. Just how bad are the numbers? Well, 2010 was the last five-year peak, which totaled 27,550 cases. It’s currently September of 2012, and the numbers last reported to the CDC were at 29,834, and that doesn’t even include over 3,700 cases in Minnesota that haven’t been officially reported to the CDC yet. These numbers, which include 14 deaths (primarily of babies under 3 months), may very well end up doubling the 2011 total of 18,719 if they continue at the current rate through the end of the year. It’s the biggest pertussis outbreak since 1959.
Not surprisingly, the majority of the states leading in pertussis cases are also among those that offer personal belief exemptions. Washington, despite their new law, is sitting at 4,190 cases, quadrupling their 2011 count of 965. This is the state where 7.6 percent of parents opted for exemptions (among all grade levels, not just kindergarten) in 2008-09, more than four times the national rate of about 1.5 percent. Minnesota and Wisconsin have similarly high rates and both have personal belief exemptions. The most recent numbers out of Minnesota are 3,748 — they had just 661 cases last year. Wisconsin is leading the nation with 4,640 cases, up from 1,192 in 2011, at last report in the Sept. 28 Morbidity and Mortality Weekly Report (pdf) at the CDC.
But the increases are being seen across the nation, as this CDC map shows. Texas (1,287 cases to date this year), Pennsylvania (1,428 cases) and Colorado (897 cases, though they averaged 158 over the past four years) are among other states with personal belief exemptions (though the Texas one has significant restrictions and hoops to jump through). But it’s clear the decreased effectiveness of the vaccine is playing the biggest role, especially in places like Iowa (1,168 cases) and New York (2,107), neither of which offer personal belief exemptions.
Again, though, a less effective vaccine does not mean a worthless vaccine. It still offers 85 percent protection when you get the shot or the booster, and even as it loses some effectiveness as the years go by, you’re far less likely to have a severe case if you do get the disease. And you’re protecting those around you, including the babies who have only been here a few months and are the most susceptible to catching and dying from the disease.
Bottom line — it’s worth it to get the shot, and to make sure your kids do too.
Opinions expressed in this article do not either necessarily reflect or conflict with those of the DXS editorial team or contributors.
[Tara Haelle (www.tarahaelle.com) is a health and science writer and a photojournalist based in Peoria, IL after years as a Texan, where she earned her undergraduate degrees and MA in journalism at UT-Austin. She’s the mental health editor for dailyRx.com in addition to reporting on pediatrics, vaccines, sleep, parenting, prenatal care and obesity. Her blog, Red Wine & Apple Sauce, focuses on health and science news for moms, and you can follow her on Twitter at @health_reporter and @tarasue. She’s also swum with 9 different species of sharks, climbed Kilimanjaro and backpacked in over 40 countries, but that was in the years of B.C. (Before Children). She finds that two-year-olds are tougher to tussle with than tiger sharks.]
Children working in a London hosiery mill around the turn of the century. Did they have “Nature-Deficit Disorder (TM)”? Source.
Maybe you’ve heard of the scourge plaguing modern-day children, the one known as Nature Deficit Disorder (TM). You won’t find it in any of the standard diagnostic manuals used to identify true disorders, but the “disorder” arises, so the story goes, as a result of keeping children inside for fear of their safety and “stranger danger,” loss of natural surroundings in cities and neighborhoods, and increased attractions indoors that prevent spending time outdoors.
This “disorder” is supposed to be an effect of modern times, the combined effects of controlling and fearful parents along with the irresistible screen-based attractions indoors. As a result of this “disorder,” children can allegedly be susceptible to any number of ills, including less respect for and understanding of nature, depression, shorter life spans, and obesity.
Concerns like these, it seems, have arisen with the advent of each new technological advance. One wonders if the invention of the wheel raised alarms that children might move through their natural surroundings too quickly to take them in. At any rate, while the person who invented this disorder, Richard Louv, has actually trademarked the term, it doesn’t seem to have made a big splash in the scientific literature. Given that studies are lacking–i.e., completely absent–about “nature deficit disorder,” one thing we can do is take a look back at how children lived before the technological age to see if their indoor-outdoor lives and exposure to the natural world were substantially different.
Go far enough back in human history, and of course, we all spent a lot of time outside. But how did we spend our time with the rise of civilization? Children in agrarian societies then and now worked from dawn to dusk as part of the family to put food on the table. In such a position, they certainly had no lack of exposure to nature, although how much they appreciated that endless grind could be in question. That is, of course, if they didn’t die in infancy or early childhood, as a large percentage of them did in spite of all that fresh air and time outside.
But what happened with children and how they spent their time with the rise of towns and cities? In early times, many of those cities were walled compounds, not necessarily hives of scum and villainy, but generally stacks upon stacks of living quarters existing solely for functionality. Nature? Outside the walls, where danger–including the most extreme kind of “stranger danger”–lurked. Cities that lacked walls, as ancient Rome did for a long period, still were more focused on efficient crowding and function far more than on nature, with only the wealthy having gardens, the modern equivalent of today’s back yards. In general, there were people, there were buildings, and there were more people. Not wildly different from, say, Manhattan today–except for that whole natural jewel known as Central Park.
This piling on of people, brick, mortar, more people, and wood continued for children who didn’t live in agrarian societies. With the Industrial Revolution, what may have really been a nature deficit disorder for a child living, in, say, London, became a genuine threat to health. While they certainly didn’t have television to keep them indoors, they also didn’t have child labor laws. The result was that children who once might have been at work at age 4 in a field were now at work at age 3 or 4 in a factory, putting in 12 or so hours a day before stepping out into the coal-smoked, animal-dung-scented air of the city.
Child labor wasn’t something confined to Industrial Revolution Britain, and it continues today, both for agriculture and industry. I do wonder if the children harvesting oranges in Brazil feel any closer to nature than the children weaving carpets in Egypt. Likely, there are deficits more profound for them to worry about.
The trigger for this overview of whether or not things have really changed over recorded history in terms of children’s exposure to the natural world is this series of articles in the New York Times (NYT). In case you hit the paywall, it is the NYT’s “Room for Debate” series and includes four articles addressing whether or not nature shows and films connect people to the natural world or “contribute to ‘nature deficit disorder’” by keeping people glued to screens instead of being outside.
Louv, the coiner of “Nature deficit disorder TM”, is one of the four contributors to the debate. He argues that viewing nature documentaries can inspire us to go outside. He also thinks many of us grew up watching “Lassie” instead of the “Gilligan’s Island” my generation watched, but perhaps there’s not a huge difference between Timmy in the well and Gilligan in the lagoon and consequent outdoor inspiration. At any rate, Louv does argue in favor of viewing nature shows, although from a very first-world perspective (like the Romans and gardens, we don’t all have back yards, for example).
Perhaps the least-defensible perspective is the argument that Ming (Frances) Kuo, an associate professor of natural resources and environmental sciences, has to offer. She compares nature documentaries to “junk food” and offers the obvious: They’re no comparison for the real world. For some reason, she implies that someone has argued that when you have access to TV, you don’t need access to nature, saying, “Scientists have been discovering that even in societies where just about everyone has access to a TV, Internet, or both, having access to nature matters.” I honestly don’t think anyone’s ever argued against that.
Does “nature deficit disorder” exist and is indoor screen time with nature documentaries to blame? In addition to the historical observations I’ve made above suggesting that children from previous eras haven’t necessarily been wandering the glades and meadows like wayward pixies, all I have to offer is a bit of anecdata, and I’m curious about the experiences of others. Historical comparisons suggest that city-dwelling children are no more deficient nature-wise today than city-dwelling children of yesteryear. But do nature documentaries help… or hinder?
When I was young and watching too much “Sesame Street,” “Gilligan’s Island,” and “Star Trek,” the only nature show available to me was “Wild Kingdom” (Mutual of Omaha’s, natch). Other than that, we had nothing unless a periodic NOVA episode came on public television.
I was interested in science and nature, but acquiring knowledge outside of what I read in a book was difficult. As a resident of the great metropolis of Waco, Tex., yes, I had a natural world to explore, but let’s face it: The primates there weren’t that interesting, and bluebonnets get you only so far. I had no access to real-life live-motion visuals, auditory inputs, or information delivered in any form except what I could read in a book. Talk about sensory limitations.
These days, my children have a nature documentary library that extends to dozens and dozens of choices. And they have watched every single one, some of them repeatedly. That’s not to say that they don’t also have dozens of well-thumbed field guides and encyclopedias covering fossils, dinosaurs, plants, bugs, sharks, rocks–the usual obsessions of the young who are interested in nature. Our “movie nights” often kick off with a nature documentary, and our pick of choice will frequently be one involving narration from David Attenborough. My children want to be David Attenborough–so do I, for that matter–and I can’t recall ever really having that feeling about Marlin Perkins or Jim Fowler.
And the upshot of that access to an expanse of nature documentaries I never had is that their knowledge of nature is practically encyclopedic. I’m the biologist in the family–or at least the one who has the biology degree–but my children often know more than I do about a specific plant or animal or ecosystem or area of the world, all thanks to these documentaries they watch. And when we’re outside, they extrapolate what they’ve learned, generalizing it to all kinds of local natural situations.
Do children today just need to be moving around more, somewhere, somehow? Oh, yes. But watching nature shows hasn’t exacerbated some kind of “nature deficit” my children might have, Minecraft obsessed as they are. And these documentaries haven’t replaced “real” nature with televised nature. Instead, the shows have expanded on and given context to the nature my children encounter, wherever that is–city, country, farm, sky, ocean, parking lot, grocery store, or even inside their own home, which is currently the scene of a sci-fi-like moth infestation that has triggered much excitement. I’d hazard that far from causing a deficit, nature shows have given my children a nature literacy that was unknown in previous generations.
What is your take on nature deficits and nature documentaries?
Several articles published in Pediatrics today discuss an issue that could affect the protection of children everywhere from vaccine-preventable diseases. The posts center on a controversy that keeps coming up related to vaccines – the use of thimerosal in them.
All three Pediatrics articles deal with the same thing: an international treaty drafted by the United Nation Environmental Program’sGlobal Mercury Partnership to reduce mercury pollution and environmental mercury exposure across the world. Great! This is an important and valuable initiative – except for one part. As part of the treaty, the UN wants to ban the use of thimerosal, a mercury-containing preservative, used in vaccines. Not so good. The short version for why? This proposed ban threatens millions of children’s lives across the world, including children in the U.S. and in other developed countries. I’ll get to the long version in a moment.
Here’s the back story:
A 1997 US FDA review of the mercury content in products revealed that the amount of thimerosal in childhood vaccines could, possibly theoretically, build up to exceed the EPA’s guidelines (but not the FDA’s guidelines or those of the Agency for Toxic Substances Disease Registry) on safe exposure limits for inorganic mercury, called methylmercury.
Methylmercury is the neurotoxin you hear about when you’re warned not to eat too much fish ( especially while pregnant). Back in 1999, scientists knew a lot about methylmercury, but they didn’t know much about ethylmercury, the type in thimerosal. As Dr. Louis Cooper and Dr. Samuel Katz, both involved with the 1999 recommendations, put it, “the absence of clear data for ethylmercury did not allow any assumption to be made about its safety.”
Meanwhile, debates were raging in Congress about concerns over vaccines and autism, fueled by the now-retracted and thoroughly debunked (pdf) study by Andrew Wakefield linking the MMR vaccine to autism. Parents were scared and confused. Media coverage was exacerbating the impression that public health officials weren’t being forthright about vaccine risks.
So, poof! All thimerosal was pulled from childhood vaccines except the multi-dose flu vaccine, since kids getting that would only get amounts below the EPA guidelines for methylmercury (even though, again, thimerosal is ETHYLmercury).
Now fast forward to today. We know a LOT more about ethylmercury: namely, that it’s not as bad as methylmercury and sails through our bodies a lot more quickly. In fact, methylmercury’s half-life is about seven times that of ethylmercury, which does not build up in the body like methylmercury does.
“There is no credible scientific evidence that the use of thimerosal in vaccines presents any risk to human health,” writes Dr. Katherine King in one of today’s Pediatrics articles. Dozens of studies and a massive review at the Institute of Medicine back this up.
Thimerosal in vaccines is not a problem. But what is a problem is thimerosal’s PR image. Again, from one of today’s AAP articles: “Given the complexity of the science involved in making guidelines, the polarity between vaccine advocates and those believing their children have been harmed, the media’s attraction to controversy, and, in retrospect, inadequate follow-up education about the issues to clinicians and the general public, it is not surprising that the steps taken left misunderstanding and anxiety in the United States and concerns in the global public health community.”
Basically, they’re saying, yea, we kinda screwed up with conveying that thimerosal really IS safe after all. We wanted to be over-cautious before, and we were, and that was good, but now we’ve sorta dropped the ball on following through in letting you know that YOU HAVE NOTHING TO WORRY ABOUT with the ethylmercury in thimerosal. As Dr. Walter Orenstein today’s AAP articles, “Had the evidence that is available now been available in 1999, the policy reducing thimerosal use would likely have not been implemented. Furthermore, in 2008 the World Health Organization endorsed the use of thimerosal in vaccines.”
But apparently, the WHO’s endorsement can’t overcome thimerosal’s PR image problem in the eyes of the UN. And so the UN is short-sightedly and dangerously trying to ban thimerosal in vaccines.
Well, that just means getting rid of it in flu vaccines (many of which don’t even have thimerosal since they’re single-dose), so what’s the big deal anyway? The big deal is that not all countries got rid of thimerosal in their childhood vaccines. Many high-income countries like the U.S. did – because they could afford to be overly cautious.
But more than 120 middle- and low-income countries – including the developing countries where vaccine-preventable diseases have the highest rates of infection and death – have continued using thimerosal-containing vaccines because the preservative allows them to make cheaper vaccines that withstand less rigorous storage without compromising safety.
Getting rid of thimerosal would mean overhauling vaccine production and storage in those countries, which the WHO estimates would cost more than $300 million for vaccines supplied by UNICEF or the Pan American Health Organization alone. As Dr. King argues, “it is banning thimerosal that would cause an injustice to those living in low- and middle-income countries and relying on these vaccines for effective protection against many harmful infectious diseases.”
Why does this matter to people in the U.S. or in other higher income countries? Because we live in a global world. Vaccines with thimerosal are currently used to immunize about 84 million children across the world every year, saving an estimated 1.4 million lives from vaccine-preventable diseases.That also includes lives saved in developed countries, where a future outbreak could potentially be imported from other countries in which a vaccination program may have ceased following a thimerosal ban.
More simply put: If the UN forces the removal of thimerosal from vaccines, then 84 million children risk not getting vaccinated (and/or vaccinated on time) due to delays in vaccine production or due to a shortage of vaccines because of increasing costs. This, in turn, could (and likely would) mean an increase in vaccine-preventable infections, which will, in turn, kill more children worldwide and risk disease carriage to other countries.
Over and beyond the increases in vaccine-preventable infections and deaths throughout the world, a thimerosal ban in vaccines could also still pose problems for developed countries. In an emergency, as Dr. Orenstein and colleagues argue, not being able to manufacture vaccines with thimerosal could endanger lives during an epidemic if it slows down vaccine production. This proposed UN ban – and the necessity of its removal – matters.
Dr. Cooper and Dr. Katz – again, both pediatricians who were closely involved in the original 1999 decision to pull thimerosal out of vaccines – sum it up best: “The World Health Organization recommendation to delete the ban on thimerosal must be heeded or it will cause tremendous damage to current programs to protect all children from death and disability caused by vaccine-preventable diseases.”
Politics often interferes where it has no natural business, and one of those places is the discussion among a teenager, her parents, and her doctor or between a woman and her doctor about the best choices for health. The hottest button politics is pushing right now takes the form of a tiny hormone-containing pill known popularly as the birth control pill or, simply, The Pill. This hormonal medication, when taken correctly (same time every day, every day), does indeed prevent pregnancy. But like just about any other medication, this one has multiple uses, the majority of them unrelated to pregnancy prevention.
But let’s start with pregnancy prevention first and get it out of the way. When I used to ask my students how these hormone pills work, they almost invariably answered, “By making your body think it is pregnant.” That’s not correct. We take advantage of our understanding of how our bodies regulate hormones not to mimic pregnancy, exactly, but instead to flatten out what we usually talk about as a hormone cycle.
The Menstrual Cycle
In a hormonally cycling girl or woman, the brain talks to the ovaries and the ovaries send messages to the uterus and back to the brain. All this chat takes place via chemicals called hormones. In human females, the ovarian hormones are progesterone and estradiol, a type of estrogen, and the brain hormones are luteinizing hormoneand follicle-stimulating hormone. The levels of these four hormones drive what we think of as the menstrual cycle, which exists to prepare an egg for fertilization and to make the uterine lining ready to receive a fertilized egg, should it arrive.
In the theoretical 28-day cycle, fertilization (fusion of sperm and egg), if it occurs, will happen about 14 days in, timed with ovulation, or release of the egg from the ovary into the Fallopian tube or oviduct (see video–watch for the tiny egg–and Figure 1). The fertilized egg will immediately start dividing, and a ball of cells (called a blastocyst) that ultimately develops is expected to arrive at the uterus a few days later.
If the ball of cells shows up and implants in the uterine wall, the ovary continues producing progesterone to keep that fluffy, welcoming uterine lining in place. If nothing shows up, the ovaries drop output of estradiol and progesterone so that the uterus releases its lining of cells (which girls and women recognize as their “period”), and the cycle starts all over again.
A typical cycle
The typical cycle (which almost no girl or woman seems to have) begins on day 1 when a girl or woman starts her “period.” This bleeding is the shedding of the uterine lining, a letting go of tissue because the ovaries have bottomed out production of the hormones that keep the tissue intact. During this time, the brain and ovaries are in communication. In the first two weeks of the cycle, called the “follicular phase” (see Figure 2), an ovary has the job of promoting an egg to mature. The egg is protected inside a follicle that spends about 14 days reaching maturity. During this time, the ovary produces estrogen at increasing levels, which causes thickening of the uterine lining, until the estradiol hits a peak about midway through the cycle. This spike sends a hormone signal to the brain, which responds with a hormone spike of its own.
Fig. 2. Top: Day of cycle and phases. Second row: Body temperature (at waking) through cycle. Third row: Hormones and their levels. Fourth row: What the ovaries are doing. Fifth row: What the uterus is doing. Via Wikimedia Commons.
In the figure, you can see this spike as the red line indicating luteinizing hormone. A smaller spike of follicle-stimulating hormone (blue line), also from the brain, occurs simultaneously. These two hormones along with the estradiol peak result in the follicle expelling the egg from the ovary into the Fallopian tube, or oviduct (Figure 3, step 4). That’s ovulation.
Fun fact: Right when the estrogen spikes, a woman’s body temperature will typically drop a bit (see “Basal body temperature” in the figure), so many women have used temperature monitoring to know that ovulation is happening. Some women also may experience a phenomenon called mittelschmerz, a pain sensation on the side where ovulation is occurring; ovaries trade off follicle duties with each cycle.
The window of time for a sperm to meet the egg is usually very short, about a day. Meanwhile, as the purple line in the “hormone level” section of Figure 2 shows, the ovary in question immediately begins pumping out progesterone, which maintains that proliferated uterine lining should a ball of dividing cells show up.
Fig. 3. Follicle cycle in the ovary. Steps 1-3, follicular phase, during which the follicle matures with the egg inside. Step 4: Ovulation, followed by the luteal phase. Step 5: Corpus luteum (yellow body) releases progesterone. Step 6: corpus luteum degrades if no implantation in uterus occurs. Via Wikimedia Commons.
The structure in the ovary responsible for this phase, the luteal phase, is the corpus luteum (“yellow body”; see Figure 3, step 5), which puts out progesterone for a couple of weeks after ovulation to keep the uterine lining in place. If nothing implants, the corpus luteum degenerates (Figure 3, step 6). If implantation takes place, this structure will (should) instead continue producing progesterone through the early weeks of pregnancy to ensure that the lining doesn’t shed.
How do hormones in a pill stop all of this?
The hormones from the brain–luteinizing hormone and follicle-stimulating hormone– spike because the brain gets signals from the ovarian hormones. When a girl or woman takes the pills, which contain synthetics of ovarian hormones, the hormone dose doesn’t peak that way. Instead, the pills expose the girl or woman to a flat daily dose of hormones (synthetic estradiol and synthetic progesterone) or hormone (synthetic progesterone only). Without these peaks (and valleys), the brain doesn’t release the hormones that trigger follicle maturation or ovulation. Without follicle maturation and ovulation, no egg will be present for fertilization.
Most prescriptions of hormone pills are for packets of 28 pills. Typically, seven of these pills–sometimes fewer–are “dummy pills.” During the time a woman takes these dummy pills, her body shows the signs of withdrawal from the hormones, usually as a fairly light bleeding for those days, known as “withdrawal bleeding.” With the lowest-dose pills, the uterine lining may proliferate very little, so that this bleeding can be quite light compared to what a woman might experience under natural hormone influences.
How important are hormonal interventions for birth control?
Every woman has a story to tell, and the stories about the importance of hormonal birth control are legion. My personal story is this: I have three children. With our last son, I had two transient ischemic attacks at the end of the pregnancy, tiny strokes resulting from high blood pressure in the pregnancy. I had to undergo an immediate induction. This was the second time I’d had this condition, called pre-eclampsia, having also had this with our first son. My OB-GYN told me under no uncertain terms that I could not–should not–get pregnant again, as a pregnancy could be life threatening.
But I’m married, happily. As my sister puts it, my husband and I “like each other.” We had to have a failsafe method of ensuring that I wouldn’t become pregnant and endanger my life. For several years, hormonal medication made that possible. After I began having cluster headaches and high blood pressure on this medication in my forties, my OB-GYN and I talked about options, and we ultimately turned to surgery to prevent pregnancy.
But surgery is almost always not reversible. For a younger woman, it’s not the temporary option that hormonal pills provide. Hormonal interventions also are available in other forms, including as a vaginal ring, intrauterine device (some are hormonal), and implants, all reversible.
One of the most important things a society can do for its own health is to ensure that women in that society have as much control as possible over their reproduction. Thanks to hormonal interventions, although I’ve been capable of childbearing for 30 years, I’ve had only three children in that time. The ability to control my childbearing has meant I’ve been able to focus on being the best woman, mother, friend, and partner I can be, not only for myself and my family, but as a contributor to society, as well.
What are other uses of hormonal interventions?
Heavy, painful, or irregular periods. Did you read that part about how flat hormone inputs can mean less build up of the uterine lining and thus less bleeding and a shorter period? Many girls and women who lack hormonal interventions experience bleeding so heavy that they become anemic. This kind of bleeding can take a girl or woman out of commission for days at a time, in addition to threatening her health. Pain and irregular bleeding also are disabling and negatively affect quality of life on a frequent basis. Taking a single pill each day can make it all better.
Unfortunately, the current political climate can take this situation–especially for teenage girls–and cast it as a personal moral failing with implications that a girl who takes hormonal medications is a “slut,” rather than the real fact that this hormonal intervention is literally maintaining the regularity of her health.
For some context, imagine that a whenever a boy or man produced sperm, it was painful or caused extensive blood loss that resulted in anemia. Would there be any issues raised with providing a medication that successfully addressed this problem?
Polycystic ovarian syndrome. This syndrome is, at its core, an imbalance of the ovarian hormones that is associated with all kinds of problems, from acne to infertility to overweight touterine cancer. Guess what balances those hormones back out? Yes. Hormonal medication, otherwise known as The Pill.
Again, for some context, imagine that this syndrome affected testes instead of ovaries, and caused boys and men to become infertile, experience extreme pain in the testes, gain weight, be at risk for diabetes, and lose their hair. Would there be an issue with providing appropriate hormonal medication to address this problem?
Acne. I had a friend in high school who was on hormonal medication, not because she was sexually active (she was not) but because she struggled for years with acne. This is an FDA-approved use of this medication.
Are there health benefits of hormonal interventions?
In a word, yes. They can protect against certain cancers, including ovarian and endometrial, or uterine, cancer. Women die from these cancers, and this protection is not negligible. They may also help protect against osteoporosis, or bone loss. In cases like mine, they protect against a potentially life-threatening pregnancy.
Are there health risks with hormonal interventions?
Yes. No medical intervention is without risk. In the case of hormonal interventions, lifestyle habits such as smoking can enhance risk for high blood pressure and blood clots. Age can be a factor, although–as I can attest–women no longer have to stop taking hormonal interventions after age 35 as long as they are nonsmokers and blood pressure is normal. These interventions have been associated with a decrease in some cancers, as I’ve noted, but also with an increase in others, such as liver cancer, over the long term. The effect on breast cancer risk is mixed and may have to do with how long taking the medication delays childbearing. ETA: PLoS Medicine just published a paper (open access) addressing the effects of hormonal interventions on cancer risk.
Looking to let go of a little “mommy guilt” for using the television now and then to give yourself a breather? There may be plenty of evidence that leaving children to watch too much television is a bad idea, but there is something to the idea that educational TV is, well, educational. We have the brain scans to prove it!
A study published in PLOS Biology used functional MRI scans to check out the brains of 26 children and 20 adults while they watched 20 minutes of Sesame Street. The actual purpose of the study wasn’t to find out if Sesame Street was educational per se. Rather, it was to observe the neural processes in the brain while a child is learning “naturalistically” and then see whether what they saw could predict how well the children would perform on standardized IQ tests.
Often, participants in studies receive fMRI scans while they are doing some sort of task that is supposed to simulate learning and/or stimulate certain neural processes. For example, a study subject might be asked to put together a three-dimensional puzzle on a computer (so their head remains still enough for the scan) to see how the brain interprets spatial relations.
However, these sorts of oversimplified “lab” tasks are not always representative of real-world activities, so it’s not clear whether what the researchers see on the brain images during these tasks is necessarily indicative of what REAL-life spatial relations thinking looks like. Are the neural processes seen in an fMRI scan while putting together blocks on a computer screen the same as what’s seen in the brain while a person builds a treehouse?
In this study, the researchers found a partial answer to exactly that kind of question, and the answer is no.
The children in study, ranging in age from 4 to 11 and all typically developing, watched the same 20-minute montage of short clips with Big Bird, Cookie Monster, the Count, Oscar and the rest of the gang teaching numbers and letters, shapes and colors, planets and countries, and so on. Meanwhile, the fMRI was taking a snapshot of their brain every two seconds.
The fMRI (which uses a giant magnet, not radiation, to peek into the brain) works by dividing the brain into a 3-D grid so that it can measure the intensity of the brain signals in each little section (about 40,000 of them, called voxels). The researchers collected a total of 609 images of each participant’s brain, which they could then use to map out the neural processes of the participants while they were watching.
They also had the children (23 of them), in a separate fMRI scanning period, perform a one of those lab-only fMRI tasks. In this case, the kids matched isolated pairs of faces, numbers, words and shapes on the computer (they pressed a button if the two images shown matched) while the fMRI images of their brains were created.
Finally, the children (19 of them) took IQ tests that primarily tested their math and verbal skills. Then the researchers analyzed the maps of neural processes in the children and their comparisons with the adults.
They found a couple of interesting things. First, the kids whose neural “maps” were most similar to the adults also performed the best on the IQ tests. This means kids’ brain structure matures in a predictable way, which the researchers called “neural maturity.”
“Broadly speaking, the children showed group-level similarity to adults in cortical regions associated with vision (occipital cortex), auditory processing (lateral temporal cortex), language (frontal and temporal cortex), visuo-spatial processing and calculation (intraparietal cortex), and several other functions,” the authors wrote.
The fMRI scan on the left represents correlations in neural activity between children and adults, in the middle between children and other children, and on the right between adults and other adults. Such neural maps, says University of Rochester cognitive scientist Jessica Cantlon, reveal how the brain’s neural structure develops along predictable pathways as we mature.
Second, the brain maps created during the Sesame Street viewing accurately predicted how the children performed on the IQ tests. Kids who did better on the verbal tasks showed more mature neural patterns in a part of the brain that handles speech and language, called the Broca area. Meanwhile, the kids whose math scores were highest had more neural maturity in a part of the brain that processes numbers, called intraparietal sulcus.
But the researchers’ other finding was that those areas of neural maturity seen during Sesame Street viewing — the ones that matched up with the children’s scores on the IQ test — were not seen during the fMRI task of matching faces, numbers, words and shapes. Basically, the “let’s try to simulate what learning looks like in the brain” task designed specifically for fMRI scans didn’t help much. But the more naturalistic, organic learning that takes places while watching Sesame Street did work.
Researchers now know they can use activities like viewing educational TV to scan children’s brains and learn more about how they learn — and it’s more accurate and helpful than invented computer tasks. It’s possible this technology and research could be applied to understanding better what’s going on with certain learning disabilities.
But a nice additional finding is that, hey, Sesame Street really IS educational! Of course, my son’s favorite show is a different PBS production — Dinosaur Train (which I admit I enjoy too) — so I also feel a better that little D spends a half hour or two, several days a week, learning from Buddy the Tyrannosaurus Rex, Tiny the Pteranodon, Mr. Conductor and Dr. Scott the Paleontologist about dinosaurs, carnivores, herbivores and how to test a hypothesis. All aboard!
An infant girl suffering from pertussis, a vaccine-preventable disease, struggles to breathe. Those indentations in her ribs are one of the signs of her extreme difficulty drawing breath. Via CDC.
What’s not to fear directly about vaccines? There’s a needle that someone pokes into your child. Your child screams. You tense up. What’s in there? you wonder. Viral or bacterial bits that, in ways that are mysterious to a non-immunologist, will keep your child well when intuition seems to say they ought to make your child sick.
Needles, screaming, microbial bits…these naturally would make any parent blanch. The number of vaccines has added to the fear for at least a decade, leading to non–evidence-based calls to “spread out” the schedule or reduce the number of vaccinations.
In fact, the evidence supports the schedule as it’s recommended.
The fear of vaccination is not new. Since Edward Jenner and his cowpox inoculation at the turn of the 19th century, people have latched onto the fear of the known—those needles!—and unknown—what’s in those things?
What might be considered the first anti-vaccine cartoon appeared in response to Jenner’s proposed inoculation of cowpox to combat smallpox.
The vision of cows growing out of arms is comical, but the reality of possible side effects from today’s vaccines can lead some parents to keep their children away from the doctor’s office. Indeed, this anxiety has done so since the days of the 19th century anti-vaccination leagues, aligned against the widespread use of Jenner’s smallpox vaccine.
The vaccine wars in those days were just as bitter and divisive as they are today, including an 1885 march in England in which anti-vaccination forces carried a child’s coffin and an effigy of Jenner himself. Today’s most fanatical crusaders against vaccines may not carry coffins or effigies, but death threats against those who promote vaccines for public health are not unknown.
The fact that the vast majority of parents overcame those fears and had their children vaccinated has led to some of the greatest public health successes of the 20th century. Thanks to the willingness of people to participate in vaccination programs, smallpox disappeared and polio became a thing of the past in much of the world. Indeed, people in those eras knew, often from personal experience, what these diseases could do—maim and kill—and the fear of those very real outcomes outweighed fears of the vaccinations.
But today, we’re different. In the United States, most of us under a certain age have never witnessed a death from diphtheria or tetanus or smallpox or measles. We haven’t seen a child drained of life as a rotavirus rapidly depletes the molecules she needs to live. Many of us have not witnessed the sounds of pertussis, the vomiting, the exploding lungs in an agony of infant death. Why? Because of vaccines.
This very success has, ironically, led to the resurgence of fear and misgiving about vaccines. No longer weighed against anxiety of death or disability from disease, the fear of vaccines now aligns against the bright picture of a nation of children largely free of life-threatening illness.
Without the collective memory of days when children played on the playground one day and died the next of vaccine-preventable disease, the calculus of parental fear pits only the side effects of vaccines against the healthy child. Vaccination requires intentional agency—parental agreement—to impose on that healthy child the very small risk that vaccines carry. Some parents simply are not comfortable either with that intentionality or that risk.
Feeding this reluctance is the explosion of Internet sites that warn against vaccines or disseminate incorrect information about them. The Centers for Disease Control and Prevention (CDC) has provided abundant information about vaccines, including a page devoted to countering erroneous information with facts.
This information will not move the fiercest anti-vaccine groups that lump the CDC in with pharmaceutical companies and others in an alleged conspiracy to harm millions via a money-making vaccine industry. However, it certainly helps concerned parents who simply seek to calm fears, weigh evidence, and make an informed decision about choosing vaccines over the life-threatening illness and compromised public health that result when people don’t vaccinate.
Indeed, these threats to public health have grown considerably with recent large outbreaks of measles and pertussis, including a growing measles outbreak in Europe involving more than 26,000 cases of measles, more than 7000 hospitalizations, and nine deaths as of this writing. The growing threat has led to calls for more stringent requirements for childhood vaccines, including dropping exemptions and requiring that all children be vaccinated over parental objections. This tactic likely would increase vaccination rates among children attending school.
But instead of strong-arming parents into having their children vaccinated, what we really need is a two-fold approach to education. First, we need sober, non-sensationalist reporting from the news media about vaccine-related stories, including stories about side effects, research, and court cases. These articles—and their sensational headlines—are in all likelihood among the prime drivers of the rumor mill against vaccines.
Second, when parents read these stories and turn to a medical professional for input, that input must come as part of a two-way communication between the health professional and the parent, not in lecture format or as patronizing. A little, “I understand your concerns because I’ve had them, too, but here’s what I know that gives me confidence in vaccines,” is considerably better than, “Your child has to be vaccinated, or you can get out of my office.” The onus is on parents to ask with open minds and an understanding that the medical professional in front of them has likely devoted considerable time to gaining the education and expertise necessary to address their questions. Health care isn’t a competition about who knows more. It’s about evidence-based health practices.
As centuries of history attest, no efforts will completely eradicate vaccine fears. Motivations fueling anti-vaccine sentiment that go beyond information gaps range from personal economic benefit to a desire to out-expert the experts to the inertia of fear.
But a careful and persistent information campaign and outreach efforts from medical professionals in the trenches may help keep vaccination rates sufficiently high. Parental investment in gaining information from trained professionals and making decisions based on facts rather than fear is also an indispensable component. To ensure adequate rates requires either these efforts or a resurgence of the deadly diseases that have graphically demonstrated the real balance of the threats at issue here.
Which one would we rather have?
Emily Willingham, Double X Science Editor Twitter, @ejwillingham ———————————————————————— A version of this post originally appeared on the blog of PKIDs, Parents of Kids with Infectious Diseases. The mission of PKIDs includes educating the public about infectious diseases and methods of prevention and transmission. Follow PKIDs on Twitter @PKIDs.