By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger
By now, most people have heard that 28 pregnant women in the United States have died from complications of H1N1 influenza (swine flu), but the details as to why it is so dangerous to pregnant women have been a little fuzzy. There are a couple of reasons why the combination of pregnancy and this particular virus is so dangerous:
Suppressed immune system: Pregnant women have a suppressed immune system, which is nature's way of allowing a mother to carry a "foreign body" in her uterus without reacting to the baby's possibly different blood type, waste products and just the fetus in general (after all, half of the DNA comes from the father and is therefore "foreign"). While this is wonderfully adaptive in terms of reproduction, it often means that pregnant women are plagued with all sorts of colds and other illnesses that probably wouldn't have even been symptomatic in the same woman if she wasn't pregnant.
H1N1 is taking advantage of this situation, as pregnant women are six times more likely to become infected with H1N1 than people in the general population.
Lung compression: Anyone who has ever been pregnant can tell you that taking a deep breath doesn't mean the same when you are pregnant, especially in the second half of the pregnancy. Growing fetuses have to have room and they get that space from the places that the organs of the woman usually occupy. The diaphragm is pushed up and there is less room for the lungs to expand. All of this means that it is much easier for pneumonia to settle in, as it is harder to expel fluid that might accumulate.
Pregnant women do have some defenses - plenty, in fact. They should: get the H1N1 vaccine as soon as it becomes available (the injection), get the seasonal flu vaccine (also the injection), see their doctor the minute that they have any symptoms and follow his or her recommendations for treatment (Tamiflu is safe for use during pregnancy), avoid contact with sick people as much as possible, encourage all people around them (especially family members) to also get the vaccination. Although there is some debate about whether handwashing can slow the spread of H1N1, pregnant women would be wise to wash their hands frequently anyway, as there are plenty of other things that spread that way.
My advice, as someone who was pregnant during a stressful flu season, is to do what you can to stay safe and healthy - then try to relax. Have a plan in case you do get sick, so that you can take action instead of panicking. Pregnancy can be stressful enough, try to take some of the extra worry out of it if you can.
You might wish to examine the evidence regarding immune suppression among pregnant women. This thinking is outdated, and it doesn’t make sense from an evolutionary perspective. We need healthy, vigorous immune systems to ensure the next generation is brought to term. It is precisely this vigor, though, which can make some diseases very risky for pregnant women. The immune system chooses – spare mother vs spare child? Which do you think it will do, again, from an evolutionary perspective? Hence, preterm labor in some cases. Recommend research by Gil Mor PhD, Yale Reproductive Endocrinology Unit.