How Omega-3 Ensures A Healthy Pregnancy

Written by Cassi O'Brien
Reviewed by Kimberly Langdon

Expecting mothers have a million worries. Picking out a good name, getting the nursery ready, getting clothing and supplies, and keeping routine doctor’s appointments are just a few. However, the biggest worry a pregnant woman will encounter is about the health of her child and herself. Adequate medical care, a good diet, and prenatal vitamins lower the chances of experiencing many of the common complications that can occur during pregnancy and prenatal development. But the majority of prenatal vitamins and modern diets are missing a vital component: omega-3 fatty acids. In this article, we’ll discuss the benefits of taking omega-3 during pregnancy.

Is there a proper omega-3 dosage during pregnancy?

It has been advised that pregnant women maintain a minimum omega-3 intake of 300 mg per day. There are a few brands that offer prenatal vitamins with omega-3 included in their ingredients but the dosage amount is usually only the minimum recommended intake, averaging between 200mg and 300mg per dose.

Although the minimum is a vast improvement from not getting any omega-3 at all, additional supplementation may be needed to receive the full benefits of the essential fatty acid.

5 ways omega-3 can help during pregnancy

What benefits can taking omega-3 during pregnancy offer an expecting mother and her child? The list is fairly lengthy because omega-3 and especially the omega-3 fatty acid DHA has positive effects throughout every stage of pregnancy and continues to be extremely important during infancy.

heavily pregnant woman

1) It can help prevent miscarriage

There are only a few limited studies on the role omega-3 may play in preventing miscarriages but the results of the studies conducted are favorable. In one study, omega-3 was seen to significantly reduce the risk of miscarriage when combined with low-dose aspirin. This benefit is due to the effect omega-3 has on the blood flow to the uterus..

Having good blood flow to the uterus is vital during pregnancy. Blood carries the oxygen and nutrients needed for the fetus to grow and for the uterus to function properly. When the blood flow is poor, it can lead to complications because the uterus and fetus may begin to become starved of nutrients. This has the potential to result in a miscarriage. By keeping the blood flow at a healthy level, taking omega-3 during pregnancy can help reduce the risk of this happening. While the study showed that omega-3 was effective in this aspect, it appeared to work better when in combination with low-dose aspirin.

2) It can help prevent preeclampsia

Preeclampsia is a condition that can occur in the last trimester of pregnancy. It is marked by hypertension, loss of protein in the urine, and edema. The condition has a tendency to rapidly worsen right after the first symptoms appear. While it is more common in those who are first-time mothers, overweight women, those with preexisting  high blood pressure, or have diabetes, this is one of the leading causes for complications during pregnancy and it poses a risk to both mother and child.

Omega-3 has not been shown to cure or treat preeclampsia, but it may have preventative qualities if taken throughout the pregnancy. A study showed that women with lower levels of omega-3 and higher levels of omega-6 were up to seven times more likely to develop preeclampsia  in their pregnancy. These results were supported by a second study that also found a link between omega-3 deficiency and preeclampsia. This indicates that taking omega-3 supplements from the start of the pregnancy may prevent the development of the condition and the complications that come with it.

3) Omega-3 can prevent preterm labor

Being born prematurely can have a vast amount of negative effects on a baby because organs do not get the chance to completely develop, especially the lungs and the brain. These effects can sometimes be life-threatening or permanent, even with the best medical care available. So, carrying a baby fully to term is essential for the baby’s health. Ina few studies, omega-3 deficiency was linked to increased risk for delivering prematurely.

A study published in 2020 showed that women who took omega-3 supplements had a lower chance of delivery preterm and premature rupture of membranes but also had a higher chance of a prolonged gestation.

It has been observed that high levels of omega-6 are linked to shorter pregnancies. This was true in the 1992 study as well. The olive oil group, who had the shortest pregnancy, were found to have significantly higher omega-6 levels by the end of the study. The reasons why omega-6 shortens pregnancy are debated but we know that omega-3 balances out the negative effects of omega-6.

Omega-6s cause more inflammation which is linked to premature births while omega-3s have anti-inflammatory effects. Due to only having a few limited studies on the topic, more research is needed but the evidence so far indicates that omega-3 supplementation, especially in the third trimester, may prevent premature delivery and low birth weight.

taking omega-3 during pregnancy can result in healthy baby

4) Omega-3 helps build baby’s healthy brain

Brain health and omega-3 are deeply intertwined. DHA, an omega-3 fatty acid, is a building block for brain cells. It is the primary fatty acid found within the brain and without it, the brain doesn’t function as well as it should. When it comes to a developing brain, DHA is even more important. The brain develops rapidly during the third trimester to the point that at birth a newborn has between 100 billion and 200 billion brain cells. By the time a child is a year old, this number has doubled. To build these neurons, the child needs an ample of amount of DHA.

Studies have shown that women who had a high intake of omega-3 during pregnancy and while breastfeeding have children with higher IQ levels. IQ is measured by the brain’s ability to process and use information. It basically shows how well the person’s brain functions. Since DHA is vital to building brain cells, having a good supply of DHA during pregnancy leads to optimal brain function.

While supplementation of omega-3 offers great benefits for a developing brain, a deficiency of omega-3 carries a few worrisome risks. A deficiency of omega-3 during brain development has been linked to both ADHD and schizophrenia. Both of these conditions are marked by lower amounts of grey matter in the brain than normal. The lack of sufficient grey matter could be the result of the brain not having enough DHA to build that part of the brain completely.

Omega-3 DHA is essential during fetal and infant brain development, not only for ensuring that the brain develops to its full potential, but also to safeguard against the development of serious neurological disorders later in life. This is why a high DHA supplement is so vital during pregnancy.

5) It promotes good eyesight in babies

Much like with the brain, DHA is a vital building block for the eyes. It’s a structural component of the retinal photoreceptor membrane, which is vital for good vision.

study on rhesus monkies was conducted in 1986, where the monkeys that were deprived of omega-3 during prenatal development and the first few weeks after birth were shown to have below normal eyesight.

This study was supported by the results of a second study published in 1992. This study involved human participants and showed that the effects of an omega-3 deficiency on eyesight within humans were extremely similar to the effects seen with monkeys. Children whose mothers had lower levels of omega-3 during pregnancy and lactation had poorer eyesight than the children whose mothers had a decent omega-3 intake. This leads to the conclusion that omega-3 is vital to ensuring good eye development and eyesight.

Omega 3


Final thoughts on taking omega-3 during pregnancy

Omega-3 is not produced by the body so it has to be obtained either through a diet heavy in fish or a high-quality omega-3 supplement. Since the majority of prenatal vitamins do not contain omega-3s, taking an omega-3 with high DHA supplement during pregnancy can be extremely beneficial to expecting mothers and their children. Most importantly, it’s entirely safe.

Throughout the studies conducted, there was never a report of negative effects for the mother or child and omega-3 is even recommended by medical associations. Omega-3 fish oil is a safe and essential nutrient that is needed for ensuring a smooth pregnancy and a healthy child.


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