Pregnancy is a time of joy for most women and their families. But pregnancy can also be a source of anxiety and the great unknown. Ten percent of American women will experience preterm births—babies born before 37 weeks—a leading cause of infant mortality, morbidity and long-term disability.
It’s often difficult to determine the specific cause of a premature birth. Genetics likely contribute to some preterm pregnancies. And there are also some known risk factors including chronic conditions such as diabetes or high blood pressure, previous multiple miscarriages, smoking and weight issues including obesity.
For the purposes of this blog post, we’ll examine some of the research conducted on preterm birth and omega-3 supplements. We’ll also address how a simple personalized blood test of DHA levels can serve as a guide for pregnant women to help reduce the risk of preterm births.
To give you a quick summary before we dive into the science, if we look at all four of the studies we’ll be discussing today, they all lead to two pieces of advice for pregnant women seeking to supplement with DHA omega-3 as a means to improving her chances of reducing the risk of a preterm birth: 1) test omega-3 DHA status before and during pregnancy; 2) take a personalized, targeted approach to omega-3 supplementation during pregnancy based on the results of those tests.
And Now on to the Science
Let’s start with a recent analysis published in March in the European Journal of Clinical Nutrition (EJCN) that included 142 New Zealand participants from the Healthy Mums and Babies study. The new study analyzed omega-3 fatty acid status in these pregnant women who were also obese, a population known to be at risk for giving birth prematurely.
The researchers from the University of Auckland and Massey University, both in New Zealand, wanted to address their hypothesis that pregnant women with obesity would have low levels of omega-3 fatty acids and therefore might benefit from omega-3 supplements.
But what they found was not what they expected. Contrary to their hypothesis, the omega-3 status of their study population was not low—in fact it was comparable or higher compared to those reported in pregnant populations in Australia, Norway, China and Germany.
The authors suggest that the high red blood cell (RBC) levels of omega-3s were related to high fish intake (28% reported eating at least two servings/week compared with <15% eating at least two servings per week in a 2017 study of New Zealand pregnant women).
Although the authors did not collect data on omega-3 fatty acid supplementation in their study, they noted that although supplementation could have contributed to the high omega-3 levels found, it was unlikely as it’s been previously reported that only about 20% of pregnant New Zealand women consume omega-3 fatty acid supplements.
Further, they advised, omega-3 supplementation is higher in women with higher levels of education, while this study looked at women drawn from a population with high rates of socio-economic deprivation.
The researchers believe that the findings from this study highlight that it should not be assumed that groups at high risk for preterm birth have low omega-3 fatty acid status.
INFOGRAPHIC: 5 Reasons Every Pregnant Woman Needs to Know Her DHA Level
These results led the authors to reject the practice of blanket recommendations for supplementing with omega-3s in a population of pregnant women at high risk for preterm pregnancies, suggesting that approach might not be appropriate.
Rather, the authors recommended “screening to identify women most likely to benefit from [omega-3] supplementation” for preventing preterm birth.
In addition, they call for further studies to determine the impact of omega-3 fatty acid supplementation in pregnant women with adequate or high EPA and DHA levels.
The Scientific Appeal of Omega-3 DHA for Pregnant Women
Before we talk about the importance for pregnant women of knowing their omega-3 status, let’s first take a step back to look at why experts find the research on premature birth and omega-3 supplements so compelling—especially for DHA (docosahexaenoic acid), an omega-3 fatty acid found in prenatal supplements, fish and fish oil.
Scientific momentum has been building for the last several years for DHA omega-3 supplements helping prevent premature birth. Then, in November 2018, one of the most promising pieces of scientific analysis for pregnant women and omega-3s was published.
With the release of an updated Cochrane Review of 70 randomized controlled trials (RCTs) involving nearly 20,000 women, there seemed to be little question left about whether benefits exist for pregnant women in reducing the risk of preterm births and other pregnancy issues by consuming omega-3 EPA and DHA fatty acid supplements. (And that’s not even taking into consideration the additional benefits that omega-3s can provide for the mother-to-be beyond pregnancy-related assistance.)
In fact, the meta-analysis concluded there is strong evidence to suggest that women taking omega-3s during their pregnancy can reduce the risk of preterm (before 37 weeks) and early preterm (before 34 weeks) birth by 11% and 42%, respectively.
Those statistics are impressive enough. Add to that, the Cochrane Review determined that omega-3s can reduce the risk of low birthweight by 10%, as well as perinatal death by 25%.
Stating that “supplementation during pregnancy is a simple and effective way to reduce preterm, early preterm birth and low birthweight, with low cost and little indication of harm,” the researchers then went one step further, advising “More studies comparing omega-3s and placebo (to establish causality in relation to preterm birth) are not needed at this stage.”
A New Trial Finds Some Different Results
But then came the ORIP Trial (Omega-3 fats to Reduce the Incidence of Prematurity) published in the New England Journal of Medicine in September 2019. The study objective was to investigate whether taking a fish oil rich in the omega-3 fat DHA would help prevent very premature delivery (before 34 weeks).
The ORIP study authors did not find evidence to support their hypothesis that those with the lowest levels of omega-3 DHA might benefit from supplementation by reducing preterm birth risk. That conclusion was reached when they assessed baseline DHA status in their prespecified subgroup analysis. However, they also indicated that further study is needed in this area.
Results in those women with high levels of DHA showed supplementation had no effect on early preterm birth, especially for those already getting a fair amount of DHA in their diet or through supplementation.
Results from ORIP are in stark contrast to the results from the 2018 Cochrane Review, which showed significant benefits for omega-3s and healthy pregnancies.
Why are the ORIP results so different than the Cochrane Review?
Omega Quant blogged about these results, seeking to explain several potential confounding effects which could have impacted the findings.
For example, Dr. Kristina Harris Jackson, Director of Research for OmegaQuant pointed out that the ORIP trial stopped the supplements at 34 weeks gestation to avoid increasing post-term interventions, which may have simply been too soon. In most other studies, she noted, supplementation was continued until birth.
In addition, Dr. Jackson advised that ORIP included women with multiple fetuses, which is unusual because twins are known to affect gestational period. The Cochrane Review, for example, excluded twins from their inclusionary criteria.
Dr. Jackson also questioned the results in ORIP that did not find benefits in the low-omega-3 status group, even though the researchers hypothesized they would. She explained when OmegaQuant converted the DHA levels from whole blood to RBC values she found the study results in this area even more perplexing. “With 900 mg per day DHA, I’m very surprised levels didn’t increase more than 0.6%,” leading to her questioning whether compliance was an issue.
Pregnancy Vitamin with DHA: To Take or Not to Take?
The simple answer is yes. Pregnant women need DHA. But there’s a simple caveat, especially for reducing pre-term pregnancies: it’s likely dependent on your DHA level.
Here’s another reason why. In February of this year, the British Journal of Obstetrics & Gynecology shed more light on how much DHA is ideal for pregnant women, and when they should (and probably should not) supplement with DHA in an effort to reduce their preterm birth risk.
One of the biggest revelations from this analysis was that a woman’s need for getting more DHA in her diet or through supplementation seems to be highly dependent on the level of DHA in her blood. In other words, if her DHA level is already high enough, then there is probably no need to get anymore. On the other hand, if her DHA level is low, then increasing her DHA intake to get to an optimal level in the blood is a good strategy for preterm birth prevention.
Test, Test, Test
Research shows that women who have low blood DHA levels are at a 10-fold increased risk of early preterm birth.
DHA is the nutrient in omega-3 supplements thought to carry the most weight in preventing premature births. For pregnant women, there’s no better way to determine how much DHA you need than by figuring out where you’re starting from.
And testing those levels before and during pregnancy is the only way to determine omega-3 DHA status. In other words, if you find out you’re low in DHA, you and your doctor can assess the risk factor for a preterm birth and make a wise decision as to the path forward.
Fortunately, there is a test to determine your DHA omega-3 status, one that’s easy, affordable and reliable.
OmegaQuant launched the The Prenatal DHA Test in early 2019 to measure DHA in the blood, so pregnant women and their doctors can determine if she is getting enough of this important nutrient to protect herself and her baby with a full-term healthy pregnancy.
It’s Not Like Studying for an Algebra Test
It’s much easier! This simple finger-prick blood test measures the amount of DHA in the blood, with a 5% target being the most protective level. It can be done from the comfort of your own home or in a doctor’s office. Wherever you choose to do it, make sure you are keeping your doctor informed about your results and working together to make a plan to modify your diet if you need to.
Importantly, the test should be repeated throughout the pregnancy, to serve as a guide for mothers-to-be and doctors to measure, modify and monitor their DHA levels to ensure pregnant women are optimizing the protective benefits of DHA.
While it’s generally recommended that pregnant women get 200 mg daily of DHA, that’s not happening. Most pregnant women only get ~60 mg from their diet and only 10% use a supplement.
It’s also recommended that pregnant women try to consume two servings per week of low-mercury, DHA-rich fish, but it’s also unlikely that’s happening. If The Prenatal DHA Test determines lower than desirable DHA levels, basic recommendations for supplementing with DHA are as follows:
- Prenatal DHA >5%– Continue to take a daily supplement with at least 200 mg of DHA per day.
- Prenatal DHA 3-5%– Increase DHA supplemental intake to at least 600 – 800 mg of DHA per day.
- Prenatal DHA <3%– Increase DHA supplemental intake to at least 800 – 1000 mg of DHA per day.
But pregnancy is personal. And so too should determining how much DHA a pregnant woman needs.
While women can benefit from sharing with other pregnant women or those who have previously given birth what’s going on during their pregnancy––their emotions, their cravings, the way their feet swell, their problems finding the right sleep position—a beautiful part of carrying your child-to-be are the things that are unique to your pregnancy.
Therefore, taking a personalized, targeted approach to improving DHA status makes sense. Women who regularly eat fish or who take a prenatal vitamin with omega-3s may not need to add more DHA to their health regimens because they may already be at a level where those protective pregnancy benefits are already in place. Still, the only way to determine if those benefits are already in place is to test your omega-3 DHA level.