Preterm birth, which is defined as a baby born before 37 weeks of pregnancy, is incredibly common in the U.S, affecting 1 out of every 10 infants.1
When a baby is born too early, organs including the brain, lungs and liver do not have a chance to fully develop and as a result there is an increased risk of long-term neurological and other disabilities and death.
Preterm birth is the greatest factor leading to infant death, especially among those born very preterm (before 32 weeks). Babies born too early may also experience:2
Vision and hearing problems
The cause of preterm birth is often said to be unknown, and associated risk factors you may hear from your conventional physician include high blood pressure during pregnancy, infection, extreme stress, carrying more than one baby, prior preterm birth and use of tobacco, alcohol or controlled substances.
However, there are other factors that may play a primary role in preterm birth that are rarely talked about and certainly do not typically get brought up during a typical prenatal care appointment — but they should.
If you’re a parent-to-be or planning to start a family, here are tips to help support a healthy, full-term pregnancy.
Optimize Your Vitamin D Levels
The moment you find out you’re pregnant, and ideally well before, have your vitamin D levels tested and take steps to increase them if necessary — to at least 40 ng/mL.
In a study published in The Journal of Steroid Biochemistry and Molecular Biology, women with serum 25(OH)D (vitamin D) concentrations of 40 ng/mL or higher had a 57 percent lower risk of preterm birth compared to those with concentrations of 20 ng/mL or less.3
Among Hispanic women, the rate of decrease was even more striking — 79 percent — for those with vitamin D levels of at least 40 ng/mL, while black women had a 45 percent lower risk of preterm birth when their vitamin D levels were at least 40 ng/mL. The authors concluded:4
“The March of Dimes estimates that the annual cost of preterm births in the United States is $12 billion (for 455,918 children).
If approximately 50 percent of preterm births could be prevented in the general population, as this analysis suggests is possible, there could be $6 billion available for other services and more than 225,000 children and families spared this trauma.
In light of this, practice guidelines at the Medical University of South Carolina (MUSC) and other institutions are currently being changed to prospectively target 40 ng/mL for pregnant women with the goal of dramatically lowering preterm birth rates.”
Separate research has also revealed that the risk of preterm birth significantly decreased as levels of vitamin D increased up to about 40 ng/mL and then plateaued.5
Yet another study found women with the lowest levels of vitamin D were 1.5 times more likely to deliver early than those with the highest levels, perhaps because vitamin D helps reduce bacterial infection in the placenta, which may trigger early delivery.6
Vitamin D Screening and Monitoring Are Key
Vitamin D screening is key, as this is the only way to determine whether you might be deficient or not, and regular testing is important to make sure whatever dosage of vitamin D you're taking is sufficient to reach clinically relevant levels.
GrassrootsHealth, which is compiling vitamin D data from a number of population-based studies, recommends maintaining a vitamin D blood serum level of 40 to 60 ng/mL to protect your and your baby's health.
However, according to previous studies, your levels need to be above 50 ng/mL to protect your baby from serious complications, such as preterm delivery and preeclampsia.7 So please, if you’re pregnant, make sure to get your 25 hydroxy D levels checked.
While optimizing your vitamin D through sensible sun exposure is best, if this isn’t possible Dr. Bruce Hollis’ research indicates that 50 percent of women can achieve this level with 4,000 IUs daily during pregnancy and 6,400 IUs (for nursing mothers) of vitamin D3 on a daily basis.
But again, you’ll need to have your vitamin D levels tested and monitored to be sure you’re within the optimal range.
Increase Intake of Omega-3 Fats
Research has linked inadequate intake of animal-based omega-3 fats, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in pregnant women to premature birth, increased risk of preeclampsia (a risk factor for preterm birth) and low birth weight, in addition to hyperactivity in children.8
A recent study published in the journal Prostaglandins, Leukotrienes and Essential Fatty Acids also found supplementation with the omega-3 fat DHA during pregnancy increased gestation by about three days while also reducing early preterm births (those before 34 weeks of pregnancy).
The study, which included an analyses of two clinical trials from the U.S. and Australia, found that daily DHA supplements for pregnant women could prevent more than 106,000 high-risk early preterm births in the U.S. and about 1,100 such preterm births in Australia each year.9
The American Dietetic Association and Dietitians of Canada recommend that pregnant and lactating women (along with all adults) consume at least 500 milligrams (mg) of omega-3s, including EPA and DHA, daily.
The European Commission recommends that pregnant and lactating women consume a minimum of 200 mg of DHA, in particular, per day.10
In a study of more than 2,000 women, the majority did not meet these recommendations. In fact, only 27 percent of pregnant women and 25 percent of women at three months postpartum met the EU’s DHA recommendation.11
What’s the Best Way to Increase Omega-3 Fat Levels?
Overall, 79 percent of the omega-3s in the women’s diets came from seafood, fish and seaweed products, with the majority from salmon; however, this often wasn’t enough to provide therapeutic levels of omega-3s that are critical for infant development.
Health Canada recommends pregnant women consume one to two portions a week of fish high in omega-3 fats to help increase levels. The study also found that women taking an animal-based omega-3 fat supplement were much more likely to meet the recommendations.
You’re probably aware that if you don’t eat a lot of fish you can supplement your diet with omega-3 fats via fish oil. Less widely known is that you can also get your omega-3s from krill oil, and it may, in fact, be preferable to do so.
The omega-3 in krill is attached to phospholipids that increase its absorption, which means you need less of it.
Additionally, it naturally contains astaxanthin, a potent antioxidant — almost 50 times more than is present in fish oil. This prevents the highly perishable omega-3 fats from oxidizing before you are able to integrate them into your cellular tissue.
In laboratory tests, krill oil remained undamaged after being exposed to a steady flow of oxygen for 190 hours. Compare that to fish oil, which went rancid after just ONE HOUR. That makes krill oil nearly 200 times more resistant to oxidative damage compared to fish oil.
If you don’t regularly eat safe forms of fish like wild Alaskan salmon or sardines, I recommend supplementing with krill oil before and during pregnancy as well as while breastfeeding.
Does Calcium Buildup Play a Role?
Calcium buildup is already linked to a number of health problems, like stiff arteries and kidney stones. The buildup is the result of calciprotein particles, or mineral clusters, that float in your bloodstream and become deposited in your tissues. Recent research now suggests calcium buildup in the womb may be involved in preterm births as well, particularly those caused by preterm premature rupture of the membranes (i.e., PPROM, or water breaking too early).12
The study found higher levels of calcium deposits in the amniotic sac in cases when the water broke too early compared to full-term births or premature births that did not involve PPROM. The researchers also found that amniotic fluid may produce calciprotein particles, and in preemies there are also lower levels of fetuin-A in the fluid.
Fetuin-A is a protein that helps prevent calcium deposits from being deposited in places where they may cause harm. In the amniotic sac, calcium proteins may lead to less flexible membranes, possibly contributing to PPROM and therefore premature birth.
“To have a new potential mechanism for one significant form of preterm birth is quite exciting,” said Dr. Edward McCabe, chief medical officer of the March of Dimes, who wasn’t involved in the study, told STAT.13 After the research is confirmed, the next step will be figuring out how to detect and prevent the problem in pregnant women.
Preterm Birth Is Associated With Higher Uric Acid Levels Later in Life
The long-term effects of preterm birth are still being explored, but research suggests there may be considerable health repercussions later in life. For instance, a study published in the Journal of Pediatrics revealed uric acid levels are greater in adolescents born prematurely than in those born at full term.14
Uric acid drives up your blood pressure by inhibiting the nitric oxide in your blood vessels. Nitric oxide helps your vessels maintain their elasticity, so nitric oxide suppression leads to increases in blood pressure. The researchers found the difference in uric acid levels among people born prematurely and those born full term “could contribute to greater BP [blood pressure] among individuals born prematurely.”
US Earned a ‘C’ Grade on Preterm Births
Preterm births are one of the factors propelling infant mortality rates upward in the U.S., which has one of the highest rates of preterm births among developed countries. According to a Premature Birth Report Card released by the March of Dimes, the U.S. earned only a “C” grade for its premature birth rate, which is subpar for a country with the most expensive health care system. Worldwide, 15 million babies are born premature and nearly 1 million die as a result. According to the March of Dimes:15
“With a grade of ‘C,’ the United States has a long way to go in reducing our preterm birth rate. In the U.S., 1 in 10 babies is born too soon, and the preterm birth rate is higher than that of most high-income countries.”
Simple steps, like optimizing vitamin D levels and consuming animal-based omega-3 fats, may go a long way toward reducing this number.