Topic of the Month

Research Update: Prematurity Research, Omega-3 and Omega-6

Julia Bird

November 7, 2018

Preterm births are a serious health issue around the globe. Any birth that occurs before 37 weeks of gestation is considered a preterm birth. Approximately one in 10 babies worldwide are born preterm, which means that there are 15 million preterm births each year. It seems that rates of preterm birth are actually slowly increasing.  

Health Problems with Preterm Birth

Babies need at least 37 weeks for their bodies to develop normally. Birth complications from preterm birth occur because preterm infants’ organs are not yet adapted for life outside the protective environment of the womb. The earlier that the birth occurs before the due date, the greater the health impact1. The main health problems just after birth for infants born preterm include breathing difficulties due to immature lungs, feeding difficulties, problems maintaining the right body temperature and an increased risk of infections2,3. Long-term, infants born prematurely can suffer from a range of ailments ranging from mild to severe. Infants born close to the 37-week mark can typically expect to live a normal life, but infants born much earlier (generally less than 28 weeks gestation) may experience severe developmental delays, and have chronic health conditions such as cerebral palsy and permanent damage to the lungs, eyes, heart and ears1,4. Preventing preterm birth, and lessening its consequences, is vital to protect millions of preterm babies born each year.   

Preterm Birth Risk Factors

While in many cases, it is not possible to find an exact cause of preterm birth, a number of risk factors have been identified. A combination of genetics and environmental factors is believed to contribute to the risk of giving birth early1. Mothers who are very young or very old, or who have a short interval between births, are more likely to have a preterm birth. Multiple births are more likely to arrive early. Certain infections can increase the chances of preterm birth, and lifestyle factors such as intense physical work, psychological stress and cigarette smoking contribute as well1. The factors – infection and lifestyle – are related to the process of inflammation, which is a normal response to infection and stress but with negative health consequences.   

Omega-3, Omega-6, and Preterm Birth: Mothers and Babies

The omega-3 and omega-6 fatty acids have several important roles in the body, and one of the most important is that they are building blocks for messenger molecules in the body. One type of these messenger molecules, called prostaglandins, are an important part of childbirth because they prime the muscles in the uterus for labor5. The long-chain omega-6 fatty acid, arachidonic acid, is used by the body to make prostaglandins that have a strong biological effect5. Biologically weaker prostaglandins are made from long chain omega-3 fatty acids [6]. While it seems that it is good to have plenty of omega-6 to support the processes behind active labor, high levels may actually be excessive, possibly increasing risk of early labor7,8. Some researchers believe that omega-3 fatty acids may balance omega-6 fatty acids by producing weaker prostaglandins that are less likely to lead to preterm labor8.

Preterm infants may also need to be provided with additional long chain omega-3 fatty acids because they have missed the critical period in the womb when the main transfer of omega-3s occurs, and their immature metabolism means that they cannot make the right types of omega-3s themselves yet9

Long chain omega-3 fatty acids, when given to women during pregnancy, have been shown to reduce the risk of preterm birth in several studies10,11. Researchers estimate that gestational length is increased by two daysto two weeks11 after omega-3 supplementation, and that preterm birth rates were reduced overall. Providing adequate omega-3 fatty acids to pregnant women is common-sense, and particularly so if it may reduce the risk of preterm birth. 

It is vital that preterm infants receive enough long chain fatty acids (both omega-3 and omega-6) after birth to support normal cognitive and physical development12,13. During their first week of life, preterm infants’ long chain fatty acid supply diminishes, and they must be provided with additional fatty acids to make sure that they do not become deficient13. Some experts suggest that omega-3 and omega-6 fatty acid requirements for preterm infants may be two to three times higher than what is currently provided in infant nutrition products and medical nutrition products14

References

  1. Blencowe, H.; Cousens, S.; Oestergaard, M.Z.; Chou, D.; Moller, A.B.; Narwal, R.; Adler, A.; Vera Garcia, C.; Rohde, S.; Say, L., et al. National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet 2012, 379, 2162-2172. 10.1016/S0140-6736(12)60820-4.
  2. Ramachandrappa, A.; Jain, L. Health issues of the late preterm infant. Pediatr Clin North Am 2009, 56, 565-577, Table of Contents. 10.1016/j.pcl.2009.03.009.
  3. Verklan, M.T. So, he's a little premature...what's the big deal? Crit Care Nurs Clin North Am 2009, 21, 149-161. 10.1016/j.ccell.2009.03.001.
  4. Glass, H.C.; Costarino, A.T.; Stayer, S.A.; Brett, C.M.; Cladis, F.; Davis, P.J. Outcomes for extremely premature infants. Anesth Analg 2015, 120, 1337-1351. 10.1213/ANE.0000000000000705.
  5. Carlson, N.S.; Hernandez, T.L.; Hurt, K.J. Parturition dysfunction in obesity: time to target the pathobiology. Reprod Biol Endocrinol 2015, 13, 135. 10.1186/s12958-015-0129-6.
  6. Calder, P.C. Marine omega-3 fatty acids and inflammatory processes: Effects, mechanisms and clinical relevance. Biochim Biophys Acta 2015, 1851, 469-484. 10.1016/j.bbalip.2014.08.010.
  7. Facchinetti, F.; Fazzio, M.; Venturini, P. Polyunsaturated fatty acids and risk of preterm delivery. Eur Rev Med Pharmacol Sci 2005, 9, 41-48. 
  8. Makrides, M.; Best, K. Docosahexaenoic Acid and Preterm Birth. Ann Nutr Metab 2016, 69 Suppl 1, 29-34. 10.1159/000448263.
  9. Koletzko, B. Should Women Providing Milk to Their Preterm Infants Take Docosahexaenoic Acid Supplements? Clin Perinatol 2017, 44, 85-93. 10.1016/j.clp.2016.11.002.
  10. Yelland, L.N.; Gajewski, B.J.; Colombo, J.; Gibson, R.A.; Makrides, M.; Carlson, S.E. Predicting the effect of maternal docosahexaenoic acid (DHA) supplementation to reduce early preterm birth in Australia and the United States using results of within country randomized controlled trials. Prostaglandins Leukot Essent Fatty Acids 2016, 112, 44-49. 10.1016/j.plefa.2016.08.007.
  11. Kar, S.; Wong, M.; Rogozinska, E.; Thangaratinam, S. Effects of omega-3 fatty acids in prevention of early preterm delivery: a systematic review and meta-analysis of randomized studies. Eur J Obstet Gynecol Reprod Biol 2016, 198, 40-46. 10.1016/j.ejogrb.2015.11.033.
  12. Brenna, J.T. Long-chain polyunsaturated fatty acids and the preterm infant: a case study in developmentally sensitive nutrient needs in the United States. Am J Clin Nutr 2016, 103, 606S-615S. 10.3945/ajcn.114.103994.
  13. Robinson, D.T.; Martin, C.R. Fatty acid requirements for the preterm infant. Semin Fetal Neonatal Med 2017, 22, 8-14. 10.1016/j.siny.2016.08.009.
  14. Lapillonne, A. Enteral and parenteral lipid requirements of preterm infants. World Rev Nutr Diet 2014, 110, 82-98. 10.1159/000358460.