Blood Pressure in Pregnancy

I was recently asked some questions regarding blood pressure during pregnancy by my colleagues at Physiquality. In preparing material, I wrote this blog, which includes very basic clinical information and explanations about this topic.

What is the normal range for blood pressure for pregnant women? What readings would fall under high blood pressure?

Blood Pressure (BP) in pregnancy is a complex topic.

First, we need to know: What are the classifications of BP?

The chart below is from the evidence-based 2014 Guidelines of the American Heart Association and the National Heart, Blood and Lung Institute of the NIH. The first number is Systolic BP or during the heart beat. The second number is Diastolic BP or between beats. These numbers are relevant for women of childbearing age.

  • Normal                        <120 mm Hg and <80 mm Hg
  • Pre-hypertensive          120-139 or 80-89
  • High BP Stage 1            140-159 or 90-95
  • High BP Stage 2            ≥ 160 or ≥ 10

Why does low BP (hypotension) occur in a healthy pregnancy?

A healthy pregnant woman with normal BP and no cardiovascular or immune system complications, will have pregnancy BP lower than her non-pregnant BP due to increased progesterone relaxing her vasculature. To create the placental and uterine blood flow, blood volume (V) expands rapidly increasing by around 40%, but stroke volume increases less, so beats per minute (pulse) may increase, systolic BP may drop 5 mm Hg and diastolic may drop 10-15 mm Hg. If V is not adequate with this relaxed vasculature, BP may drop even lower. To help maintain normal BP, women are encouraged to drink sufficient water (about 8 glasses/day) and eat enough protein (about 20-25% of daily intake) to produce a blood volume that will sustain an adequate BP. Other more severe conditions – often genetic – may also be relevant, such as postural orthostatic tachycardia syndrome.

Other causes of hypotension include lying still on the back with legs extended for long periods of time after the first trimester. The weight of the uterus impinges on the vena cava returning blood to the heart, thus reducing BP and blood flow to the uterus and placenta. Also, standing for long periods of time with a minimum of motion, as happens with teachers, cashiers, line workers and nurses in the second half of pregnancy when increasing relaxin and elastin cause further softening of vasculature. This results in difficulty returning blood from the lower limbs and reducing blood flow to the uterus and placenta.

What are hypertensive disorders of pregnancy?

According to the National High Blood Pressure Education Working Group on High Blood Pressure in Pregnancy, hypertensive disorders of pregnancy are presently classified into four categories:

  • Chronic hypertension (pre-existing)
  • Preeclampsia-eclampsia
  • Preeclampsia superimposed on chronic hypertension
  • Gestational hypertension

[The Society of Obstetricians and Gynecologists of Canada categorize these disorders as pre-existing or gestational, with the addition of preeclampsia to either category.]

Chronic hypertension is BP >140/90 prior to pregnancy or before 20 weeks. New onset of high BP after 20 weeks may indicate preeclampsia (PE), which requires further consideration. PE involves other symptoms and organs. It occurs in about 5% of all pregnancies, 10% of first pregnancies and 20-25% of women with a history of chronic hypertension. It is a serious disorder and major cause of adverse maternal and fetal outcomes, including strokes, seizures and restricted fetal growth and development.

The underlying pathogenesis of preeclampsia-ecclampsia is not yet fully understood, but is a fundamental dysfunction of the placenta leading to endothelial dysfunction and vasospasm. Possible causes include pre-existing endothelial dysfunction, metabolic dysfunction, auto-immune responses and infection. It is likely that the placenta is affected very early on, during implantation, trophoblast invasion of the uterus and opening of the spiral arteries to form the blood pool on the maternal side of the placental circulation.

Gestational hypertension is the onset of BP >140/90 after 20 weeks without other features of preeclampsia. About 1/3 of these women develop preeclampsia. Gestational hypertension is highly associated with hypertensive disorders later in life. Diabetes can also be a factor associated with hypertension.

Whenever a woman has elevated BP in pregnancy, she needs to be evaluated and have a follow up course of observation and treatment. At its most severe, a hypertensive disorder can affect all the body’s organs and systems, and can be fatal.

What can pregnant women do (diet, exercise, healthy habits) to keep their blood pressure within a normal range?

Some risk factors for hypotension or hypertensive disorders of pregnancy are inherited, others are a consequence of behavior, and many are a combination.

What can a woman do before pregnancy?

Because the events that pre-dispose a woman to hypertensive disorders may occur before she knows she is pregnant, some efforts at prevention may be helpful in the six months to a year prior to pregnancy. Preparing for the implantation period by maintaining optimal health and fitness is likely the most helpful behavior. Cardiovascular or aerobic fitness, which prevents or reduces the severity of endothelial dysfunction is highly valuable. An adequate daily nutrient intake along with sufficient water, and maintaining a BMI <25 are important factors. Women with elevated blood pressure should discuss with their care provider the balance of sodium and potassium intake, along with the total allowable amounts.

Avoiding infections or illness around the time of conception may be a factor. Hypertensive disorders are mediated by inflammation. Unfortunately, another factor may be the maternal immune response to the fetal DNA. This may also be dependent on combined maternal/paternal immune system responses.

What can a woman do once she is pregnant?

Once a woman is pregnant, maintaining optimal health and fitness continue to be important. Even if there are pre-disposing factors for disorders, she may be able to reduce the severity by staying fit, well nourished and well rested. A balanced and colorful diet, along with avoidance of alcohol, drugs and unsafe behaviors are critical.

The ability to achieve the Relaxation Response, meditation, deep breathing and hypnosis are valuable for acute BP reduction. Each of these skills is mediated by the parasympathetic nervous system response (or alpha brain rhythm) and mitigates the effects of stress on a temporary basis. Cardiovascular or aerobic fitness is effective for long-term BP reduction, as well as cardiovascular health.

Resting on the left side maximizes circulation and – if possible – finding 15 or 20 minutes to rest this way during the day is beneficial, especially if a woman’s work involves standing for long periods of time. Avoiding lying on the back or standing for long periods of time is advisable. Finding a community of support for having a healthy pregnancy can be a great asset, as well.

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How to Get Pregnant – Coaching Topic #1

Hurrah! We have power at last…a week after hurricane Irene romped through, we have juice! Thanks for bearing with us while we camped out.

So let’s get on with the topic of How to Get Pregnant, starting with why do we need to know this?

In the past few decades, the average age for a first pregnancy in the U.S. has moved from the mid twenties into the mid thirties. In the same time period, the facts of conception – sperm enters egg released in mid cycle, then zygote implants in the uterus, along with how sex allows this to happen and how to prevent it – seems to have disappeared from middle and high school health classes. If that weren’t enough, as women have become more and more essential in the work force, the cost of having children as well as starting later, have driven down the birth rate. Similar conditions exist in most developed nations, although teen pregnancy rates are lower everywhere else.

The birthing population has bifurcated – we see older women (over 35) and teens as the major groups having children. On the one hand we have been working to reduce teen pregnancy while helping older and older women become first time moms. To a certain extent, they need the same information; its just that with teens we use this information to prevent pregnancy and with older women we use information to help them increase their odds of getting pregnant.

Understanding the menstrual cycle, ovulation, charting temperature – all the basic techniques of using the “natural” method of birth control – have become the first steps of the how-to-get-pregnant coaches. Beyond this, a number of sites have their own essential lists to help women be healthy and ready. Sites such as gettingpregnant.com, pregnancy.org/getting-pregnant, and storknet.com/cubbies/preconception/ provide additional information. Many suggestions – things to avoid eating, what proteins are needed for ovulation, how to reduce stress, what to do if there are sperm problems, how to find IVF clinics, donors and surrogates – are addressed.

How effective are these suggestions? Well, research tells us they are somewhat effective. None of the sites I contacted answered my query about how they measure or assess consumer outcomes when following their suggestions.

An interesting article in the NY Times 9/1/2011, entitled Are You as Fertile as You Look? openened with this sentence: “FORTY may be the new 30, but try telling that to your ovaries.” The reality is that being under 35 is still the best predictor of how difficult it may be for you to become pregnant. As the article makes clear, looking 30 and being 30 are not the same thing. Even healthy living does not prevent the loss of good eggs.

So, what conclusions can we draw? First, even if you come from a “fertile family,” it may behoove you to have your children in your late 20s or early 30s. Second, if you are putting off having children beyond that time, ask yourself what extremes you are willing to go to to have your own biological offspring. And, third, consider adoption. Frankly, it would be wonderful if adoption were easier, but in the drive to conceive at later and later ages we see the hand of biology and understand why adoption is not easy:  Our own offspring – our own DNA out there in the world – is a heady motivation.

If you are on the pathway of becoming pregnant, being under 35 is the best ally you have. If not, maybe some of the suggestions on the web will work for you. Whatever you decide, all the best.

One parting comment:  Regular moderate exercise – while it helps you stay young and healthy – will not prevent your eggs from being popped out every month. It will help you have a healthy pregnancy if you conceive, so stay with it!

Pregnany & Parenting Coaching

Looking through incoming emails, tweets, fb notifications and e-newsletters that inhabit my inbox more and more, I noticed something interesting:  Lifestyle Coaches for people entering the pregnancy and parenting pathway. After some investigation, I found a plethora (many, many) web business/sites that offer services on everything from getting pregnant to getting your kid into college.

There are sites by enduring public health organizations that cover the range of conception, pregnancy, birth and early parenting issues – such sites as those by the Mayo Clinic, the March of Dimes, and WebMD – starting with how to get pregnant. You can also find business sites for these range of topics – such as The Bump and BabyCenter.

In addition, there are individualized sites that cover coaching for one or more parts of the process. Sites specialize in getting pregnant, being pregnant, giving birth, caring for a newborn, finding childcare, finding early childhood education, how to talk to toddlers, what to do with children of all ages, how to get them ready for school, how to encourage them in school and so on. Some specialize in a combination of two or more of these topics. Some started out specializing in one topic and are moving along as the owners or writers evolve in their lives.

I realize that this is an outgrowth of the “mommy bloggers.” Many computer literate women found blogging a way to deal with the life-changing event of having a child. For some, the internet became a means of making a living while staying home. Realizing that there was a large audience in this realm, the mommy entrepreneurs evolved…and, not all of them are mommies.

We are beginning to see the next generation:  pregnancy and parenting life coaches – individuals who may or may not have professional backgrounds in one of these areas, but are learning to turn their own experiences into businesses that help – or purport to help – others along this part of life’s path. Where does the impetus for this come from? Is it just that the internet makes a new business model possible? What else might be happening here?

For some time, I have thought that young persons entering parenthood these days are at a distinct disadvantage. Bearing and raising children is not easy or cheap. It requires a network of support and advice that used to be present in the extended family. But, we leave home and are much more mobile these days. We may live in Texas, but our baby’s grandparents live in Oregon or Brazil or Turkey. I asked my own exercise, childbirth education, and parenting clients about this. I found that many were in the classes precisely because they felt they had no firsthand experience or knowledge about what it was like to hold, feed or change a baby, let alone be prepared for birth and the sleep deprivation that followed. I also found mommy bloggers and entrepreneurs who found the impetus for their new work sprang from these issues in their own lives.

So, over the next series of blogs, I will be writing about some of these sites and services…both the professional organizations and the new mom entrepreneurs who have turned a difficult life transition into a way of simultaneously helping others while putting food on their tables. It looks to be an interesting journey and I hope you will follow along! I will get the next blog up in a few days, as soon as I am in the next location with internet access. My office is temporarily in the hurricane blackout zone of CT, but they promise me service soon. The first topic:  How to get pregnant!

Pregnancy Pathway, Outcome – Mom & Baby Health Status

This 2/1/2010 entry seems to draw attention consistently, so we decided it was worth re-posting it. The discussion concerns determinants of the health outcome for mom & baby in the Pregnancy Pathway. It reviews the pathway, and then continues to the last stage of the Pathway, the health outcome. Here’s the whole graphic:

So, the big question is: How can we predict the health outcome of mom and baby, given all the variables of preconception, conception, pregnancy, labor and birth?

Well, there are some things for which we can predict or estimate risk/benefit ratios, and there are some for which we cannot. Let’s start by going over the major things that are not very predictable. At the moment, genetics is pretty much unpredictable. Down the road…maybe…but for now, not so much. Some IVF labs claim they can slightly slightly increase the odds for one sex or the other.

Post-conception, chorionic villi sampling and amniocentesis are methods by which the genetic make-up of the fetus can be identified. These are done mainly to give parents a choice about continuing a pregnancy if there is a question about genetically transmitted disorders or conditions, such as Down Syndrome. But, for now, the best way to manipulate the genetic odds of health outcome for your offspring is to mate with someone who is healthy and has health-prone genes!

Once you are pregnant, it is clear that prenatal health care, exercise, healthy nutrition, stress management and adequate sleep play significant roles in increasing the potential for a healthy outcome for mother AND baby. In fact, not only short term, but also long term healthy outcomes are linked to these factors. These are factors within our control.

Risk factors – most of which are within in our control – that can adversely affect outcomes include environmental toxins, risky behaviors (unsafe sex, drinking, smoking or drugs), poor nutrition, sedentary behavior, stress and isolation (lack of social support). These risks, as well as the benefits, are all discussed in the previous posts.

At this point, it is important to note that there is a lot that goes into making a healthy pregnancy, birth and outcome that is within the control of the mother, providing she has family and/or social support to take good care of herself.

The labor process and birth mode can also affect health outcome, but in general the effect is short-lived. For moms who have received regular care and are in excellent health, the occurrence of a truly devastating birth outcome for mother and/or baby is extremely rare. The exception may be mental or emotional turmoil that can accompany a difficult, unexpected and uncomfortable situation, such as an unplanned cesarean birth.

 

Group exercise programs are a source of social support.

Three interesting research outcomes point to the importance of exercise groups. One is that exercise can help prevent some disorders of pregnancy, such as preeclampsia or gestational diabetes. Second is that the health benefits of exercising during pregnancy and the postpartum period are beneficial for both short and long term for mother and infant. Disorders of pregnancy are risk factors for future cardiovascular disease and metabolic disorders. Third is that exercise is most likely to occur when there is good social support.

Moving together is a “muscle bonding” experience that helps bind moms-to-be and new moms into a community of support. Within the group, moms can get help with tips for healthy eating and living, along with the support of others who know what she is experiencing. There are a lot of ways to get adequate exercise. When you are pregnant or a new mom, an exercise group can be one critical path to health and well-being.

Sex, Pregnancy, Birth Control, Viagra & War

For some time, the connections among these things have been stewing in my mind. Hoping to avoid an outright rant, I put off writing until my amygdala was calmed down sufficiently to make my key points briefly and reasonably. Global events and U.S. politics motivates me to write this blog now.

Item #1: Sex

For whatever reasons (God’s grand design, nature’s instinct for survival, your favorite theory inserted here…) sex has immediate rewards if done properly. Both men and women experience orgasm, which affects pleasure centers in the brain and encourages us to do it again.

Women’s orgasm is less tangible that men’s. It’s also more controlled in cultures where men’s pleasure is valued over women’s. In fact, in some settings – those that allow female mutilation – it is prevented as a means of controlling women and preventing infidelity or even sex for any reason other than the male’s pleasure or impregnation. Western religious and political cults are slightly more civilized in that rather than cutting women, they merely frighten them into submission.

Keep these thoughts in mind, for when we get to the end of this discussion (war), we will bring the ideas full circle and return to this point.

Item #2: Pregnancy

It’s easy to make the connection between sex and pregnancy. Unless, of course, something has prevented you from hooking up these phenomena conceptually, like being too young to understand or being prevented from figuring it out by others with social or political motives.

What makes pregnancy of interest here is that it can make even the strongest women vulnerable. Two people using one body (or three, if the male thinks the woman’s body belongs to him) places big demands on the woman’s body and depletes her physiologic resources. Even in a setting where food and shelter are abundant, it puts her internal organs under stress.

It is in the best interest of cultures to support and provide a safe environment for pregnant women. And, most importantly, to allow a woman to make decisions about when and with whom she will bear a child. Yet, we do so rarely.

Item #3: Birth Control

The great leap forward for women in the 20th Century is clearly the advancement in birth control. For the first time, by mid-Century, women could reliably prevent unwanted pregnancy before it happened. It was the 1960s (!!!) when women were finally able to gain legal control to obtain their own birth control in the U.S.

Yet, clearly, preventing pregnancy is preferable to aborting an unwanted pregnancy, which until the 20th Century really was the only reliable way to prevent carrying DNA that a woman did not wish to carry.

Why would a woman not want to carry certain DNA? To answer this, we have to look at men’s biological make-up. To oversimplify, but make a point:  When there were very few people on earth, it was understandable that the males who could impregnate many women were able to develop loyal clans. Follow this out through the centuries and you get genetically homogeneous civilizations. When conquering, rape was an important part of the process because it enabled this genetic loyalty.

The method by which women could level the playing field was abortion. The combination of maternal/fetal mortality and abortion worked to provide some balance in the civilizing forces at work as the population grew.

Item #4: Viagra

I love this:  Most insurance will pay for medications that improve erectile dysfunction, but many will not pay for birth control. There is a glut of propositions for laws prohibiting women from protecting themselves…and seven billion people later, we really do need to protect ourselves at least until we can get some colonies in space underway.

So, by now you have read enough to see the incredible irony of this situation. Despite a need to limit populations growth, there is currently such a beating-of-the-chests attitude clobbering world events, one which includes the notion of ownership of women’s bodies by men. You can get free Viagra, but the same people using the Viagra are telling women they can’t protect themselves!!

Item #5: War

This leads us to the final item…war. Right now, war is everywhere. Thanks to people who shall remain unnamed here, the notion that if you don’t like someone, it is okay to go to their country and kill them and/or takeover their way of life, has led to this “okay-ness” of waging war. Unfortunately, this bully pulpit has infiltrated civilization, which – until recently – was making pretty good progress on commonality of human existence and the need for peaceful solutions.

So, what do we see? A return to the “ethics” of war, including rape and control of women’s bodies (go back to item #1). It is interesting to me that in the U.S. there is a growing awareness among young, childbearing women that there are a lot of unnatural processes going on in birth. I am duly impressed by the extent to which young women have pressed the discussion of whether or not the way in which we birth as a nation produces the best outcomes for baby and mother.

We don’t need as much abortion as we used to. We have much more effective ways to prevent unwanted pregnancies. Our teenagers are finally getting the message in some demographics that prevention is best. If we continue as a warring nation, will we threaten this progress? This worries me. I hope we can steer our culture in a more productive direction. Women’s bodies should not be a battleground.

Preventing Prematurity

Today is a day for bloggers to raise awareness of the growing rate of prematurity in the U.S.  As a pre/postnatal fitness specialist who has been working in the field for more than 30 years, I have a number of thoughts on this topic.

I like to start thinking about this problem by thinking back 50,000 years. Back in the day when survival meant hard physical work. 

Which pregnant women survived?  The strongest, fittest and best fed.

Does it make sense, therefore, that becoming sedentary and eating junk food is going to produce healthy offspring at full term? Well, the evidence says no. This behavior is responsible for some of the growing prematurity. Women who are aerobically fit, eat a healthy diet and maintain a healthy weight generally enjoy these benefits over those who do not:

  • a healthier endometrium into which the zygote will implant
  • a healthier placenta with more nutrient delivery surface
  • reduced risk that the necessary immune system modulations of pregnancy go awry
  • better control of metabolic and cardiovascular factors that can threaten pregnancy, such as gestational diabetes or preeclampsia
  • a greater ability to physically cope with some environmental toxins

There are – of course – factors that affect prematurity in any case. But, to a certain degree, the growing rate of prematurity is another example of lifestyle-caused disorders. Some of the fix therefore requires a lifestyle that is active and health-conscious.

But, I am hopeful. I see – for the first time in a couple of decades – growing numbers of young women interested in living a healthy lifestyle…exercising, eating healthy and seeking to improve environmental conditions. I also see young women interested in preventing poor living conditions and infection rates in this country and in the developing world that have hindered progress in preventing disorders such as gestational diabetes and preeclampsia.

To these young women I say:  kudos. Keep working. We have much work to do.

To young women contemplating pregnancy in their future I say:  become aerobically fit, eat a balanced and colorful diet, spend 15 minutes in the sun most days (or, if you are at risk for skin cancer, take vitamin D), practice meditation or a simple progressive relaxation with deep breathing for 10 or 15 minutes most days.

To all the moms whose babies came too soon, my heart is with you. I know this pain.

Reflecting on Mother’s Day

Mothers make people.

Be sure to thank your mom!

It is a stunning thought that with our bodies women are able to make new people.

It is a big responsibility.

We want to give words of encouragement to all moms-to-be and new moms who take care of themselves and their little ones through healthy living!

Bless you all for all you do! For every mom who takes care of herself prior to, during and after pregnancy, the load is reduced for the March of Dimes and the White Ribbon Alliance for Safe Motherhood.

If you have questions about how to live healthy for your baby, here are some ways to get those questions answered…

• Post a question to us via Comments.

• Check our Blog archives for Pregnancy Pathway topics that can help you have a healthy pregnancy and postpartum experience, including pre-conception health, conception, exercise, nutrition, avoiding toxins, birth preparation, recovery, and other healthy behavior topics.

• Visit our website www.dancingthrupregnancy.com for tips on exercise and nutrition and for updates on current research.

If you want to help others who may not be as fortunate as you, here is another organization you can help: www.thediaperbank.org that provides diapers for those who cannot afford them.

Thanks for reading, and pass on our location. Thanks!