Nutrition for the second trimester – growth & development

During the second trimester, systems that formed during the first trimester start to become more complex and functional. Growth rate needs to be maintained, so your ongoing nutrition and general health are very important at this stage. By around 12 weeks, any miscarriages or lost pregnancies will have already occurred, and the pregnancy is deemed viable when scans are considered normal.

By now, your pregnancy is becoming more obvious and it is essential to maintain consistent weight gain.  If you gain too much weight at once, you may be at risk of Metabolic Syndrome or Gestational Diabetes. On the other hand, if you don’t gain enough weight at the right stages, there is a risk of baby having a low birth weight. Your appetite may decrease from pressure on your stomach, but you need to ensure that you eat high nutrient foods in small portions at regular times.

Even though the majority of organs form in the first trimester, your body needs a steady stream of nutrients to help feed your growing baby. For example, your levels of Vitamins C and E during the second trimester have been shown to be associated with baby’s birth weight ^[1]. During the second trimester you need an extra 300 calories a day which is equivalent to 2 slices of wholemeal toast and ½ and avocado.

Vitamin D:

In pregnancy vitamin D is important for supporting healthy bone development of the baby, as well as affecting mum’s blood pressure, mood and brain function, and immunity ^[5-6].

As breastmilk contains low concentrations of vitamin D, most of baby’s vitamin D comes from maternal stores transferred during gestation. Deficiency in vitamin D during pregnancy results in low vitamin D stores of the newborn which may affect bone development if left untreated. Vitamin D deficiency during pregnancy is also linked to a condition called preeclampsia, which is characterised by high blood pressure and increased pregnancy risks ^[7].

Along with getting a healthy dose of sunshine, you can get vitamin D from some foods.

Dietary sources of vitamin D:

Fish, mushrooms, dairy, eggs, fortified cereals and organ meats.

Vitamin C

Vitamin C is an essential micronutrient responsible for many metabolic functions within the body. During the second trimester, vitamin C is involved in collagen synthesis and metabolism of folate and iron, assisting in the absorption of dietary non-heme iron (plant sourced iron). It also acts as an antioxidant and supports normal immune system function in mum ^[2].

Dietary sources of vitamin C:

Cirtus fruits, strawberry, mango, tomato, kiwi fruit, capsicum

Vitamin E

Vitamin E functions as a lipid-soluble antioxidant, protecting cells of the body from damage by harmful free radicals, as well as helping the body form and use red blood cells and muscles. As antioxidants, vitamins E and C act synergistically to help prevent oxidative stress, which occurs when there are insufficient antioxidants to counteract the harmful effects of free radicals.

Links have been made between oxidative stress during pregnancy and the development of pre-eclampsia, and increased risk of intrauterine growth restriction and pre-labour rupture of membranes (PROM) ^[3]. Consuming plenty of antioxidants through vegetables, fruits and healthy fats is important for a healthy pregnancy.

Dietary sources of vitamin E:

Sunflower seeds, wheatgerm, almonds, avocado, olive oil, fish

Protein:

Protein helps to build your baby’s soft tissue, including the brain, the placenta, and your red blood cells. It also helps to form hair, nails, bones, and organs, and is used to create the hormones that regulate every function in the body.

During the second trimester and for the rest of your pregnancy experts recommended eating between 75 to 100 grams of protein each day ^[4]. To make sure you are getting enough protein, you should include a source of protein with every meal.

Dietary sources of protein:  

Meat, fish, eggs, tofu, legumes, nuts, quinoa, brown rice, oats.

Omega-3 (EPA & DHA)

During pregnancy, omega-3s are a critical building block of the foetal brain, eyes, and nervous system, and are associated with healthy birth weight and gestational length and immune system development.

While in the first trimester, nerve connections were built that enable your baby to move around in the womb, the second trimester involves more nerve connections and brain tissue formation ^[8]. As DHA forms part of the structural component of the brains grey matter, it is an essential nutrient for baby’s brain development and for mum’s own health and well-being ^[9].

A daily level of at least 300mg of DHA has been recommended during pregnancy, to prevent problems such as pre-term birth ^[10].

Dietary sources of omega-3 EPA & DHA:

Tuna, salmon, herring, mackerel, sardine, marine algae (algal oil).

Remember that all nutrients are important and eating a balanced diet is the best way to support a healthy pregnancy.

For additional information, here is a list of important vitamins and minerals that play a role in the second trimester of pregnancy.

Nutrient	Dietary Sources	Function
Folic acid (folate)	Green leafy vegetables	Prevent preterm birth [10] and reduce risk of preeclampsia [12]
Zinc	Seafood Lean meat	Birth weight, cell development
Vitamin D	Sunlight exposure Eggs Fish	Enhances calcium absorption, prevents Gestational Diabetes, preeclampsia, infections, helps with brain, metabolism and immune development
Iron	Red meat Spinach Lentils	Haemoglobin production (oxygen transport) & neural development
B vitamins	Lean meat Lentils Wholegrains	General cell development. Important for red blood cell production (foetal circulation)
Iodine	Seafood Seaweed Iodized-salt	Brain, neural development, general growth
Omega-3 fatty acids (DHA & EPA)	Seafood Fish	Brain & neural development, general growth
Vitamin C	Citrus fruits Tropical fruits	Cell and protein metabolism, increase iron absorption, antioxidant support, birth weight
Vitamin E	Nuts Seeds	Antioxidant support, cell growth and development, birth weight
Magnesium	Vegetables, Nuts & seeds Meat & seafood	Cell & tissue development (skeletal and muscle function)
Calcium	Dairy Green vegetables Sesame seeds	Skeleton and muscle formation, regulates circulatory system
Beta-carotene	Carrots Sweet potato Pumpkin	Antioxidant protection, eye development, general growth and development