Omega-3, pregnancy and preterm birth
Preterm birth (birth before 37 weeks gestation) is leading cause of neonatal mortality. Infants born preterm generally require care in neonatal intensive care, and can have an increased risk of a number of potentially serious complications such as cerebral palsy, respiratory distress syndrome, intraventricular haemorrhage, necrotising enterocolitis and blindness. Preterm birth cannot be easily predicted, however we can do everything in our power to prevent it.
Nutritional status during and prior to pregnancy is an important determinant of fetal health through pregnancy. Observations of populations with higher fish consumption found increased lengths in gestation. So what does fish have that potentially decreases risk of preterm birth? Fish is high in an essential fatty acid, omega-3. Omega-3 is hard to come by in any other food source, so our friends in the sea are one of the only places we can find it. There are a few omega-3’s:
- Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA): found almost exclusively in oily fish and seafood.
- A-linoleic acid (ALA): found in some nuts, linseed and canola oil, legumes and small amounts in leafy greens. ALA is generally inactive until converted to EPA and DHA, of which it only converts very small amounts.
Omega-3’s, specifically EPA and DHA play key roles in the development of the fetus, modulating inflammation and the synthesises of prostaglandins. Prostaglandins are substances that play a role in blood flow, the induction of labour and gestational length through reducing the inflammatory pathway which is linked to spontaneous preterm birth. During labour omega-3’s play a crucial role in the inflammatory cascade, blood flow and cervical ripening.
In fetal development, omega-3’s have been shown to impact the fetal brain, retina and respiratory system. Higher near-birth DHA levels in the fetus are associated with increases in brain volume that correlate with increased language and motor scores in preschool age children. Supplementation during pregnancy reduces the incidence of asthma and improves heart rate variability, with low levels of omega-3 through childhood being postulated to be a risk factor for autism spectrum disorder.
So how do I get omega 3?
- Intake of fatty fish – especially sustainably wild sourced and of a good quality.
- Supplement a good quality fish oil, that is rich in DHA. Poor quality fish oils can be contaminated with heavy metals, come from low quality processing facilities and may even be rancid. Quality is everything with omega-3 supplementation.
- Some omega-3 can be from a marine algal source, which can also be excellent – just ensure that this is a high EPA/DHA marine algae.
How much do I take?
There have been a lot of studies on supplementation in pregnant women with doses of 750-1000mg/day shown to be safe and effective.
Although there are studies on omega-3 and fish oil supplements being safe and effective for most pregnant women, always consult with your healthcare professional before starting any new supplements. There can never be a guarantee that any one supplement will prevent preterm birth for your specific situation. There is no one size fits all approach to pregnancy care, always have a team of professionals assessing your nutrition, supplements and lifestyle.
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