Fertility After Bariatric Surgery

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Diet forms a crucial component for long-term health and fertility after bariatric surgery.

First up, pregnancy is very possible after surgery. Strategic nutrition and supplement planning should be in place though to ensure adequate dietary nutrients for fertility after bariatric surgery.

Planning a nourishing diet which makes every bite count with a tailored supplement regime preconception should be a non-negotiable for fertility after bariatric surgery.

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What is bariatric surgery?

Bariatric surgery reduces the size of your stomach, and sometimes your small intestines. Vitamin & mineral supplementation is recommended for all bariatric procedures lifelong. This because the physiological changes to your stomach and/or intestines will alter how the body absorbs nutrients. This is why nutrient deficiency can be common. It also reduces the volume of food, therefore micronutrients which will be consumed.

The body will go through a phase of initial rapid weight loss after surgery until weight plateaus at about 1-2 years later based on surgery type. Given the extra nutrient requirements of pregnancy, most guidelines recommend waiting until the weight plateau before falling pregnant.

Post bariatric surgery supplementation

Post surgery multivitamin supplementation requirements will vary based on the type of bariatric surgery undertaken.

There are specific supplements available for bariatric surgery patients. Fertility and pregnancy planning will further increase the requirements for specific nutrients.

Below I discuss a few of these key nutrients, but this is general advice only. Please do not use an article you found on the internet to guide your health journey.


The big one for fertility after bariatric surgery.

Folate is crucial for the healthy closure of baby’s neural tube in early pregnancy. Folate requirements are sometimes also higher post surgery related to reduced absorption capacity. It’s also because you will be eating less food, and food is a big gateway for micronutrients.

It is likely additional top-up supplementation will be recommended beyond any multivitamin you may be taking.

A few nourishing food sources include leafy green veggies, legumes, eggs, liver and fortified breads and cereals.

Vitamin B12

Vitamin B12 absorption is aided in the body by Instinct Factor (IF). IF is a glycoprotein produced by the parietal cells in the stomach. Now, if a portion of the stomach is removed, the body’s ability to make IF is reduced.

Reduced IF equals less absorption of vitamin B12.

Deficiency of this nutrient is common amongst post bariatric surgery patients. Requirements increase to between 350-1,000ug from ~2.4ug for a healthy population.

Vitamin B12 plays a crucial role in DNA synthesis and red blood cell development. Which are all important things when growing a baby. Ensuring nutrient adequacy here so just so important.

If you are following a vegan or vegetarian diet, it is even more important to seek nutrition guidance. This is because dietary plant-based sources of vitamin B12 are hard to come by (pretty much non-existent).

Meat, seafood and eggs form most dietary sources of vitamin B12. But you can find fortified plant-milks, nutritional yeast and some mushrooms containing B12.

Vitamin D

The sunshine vitamin.

Vitamin D is a fat soluble vitamin required for strong healthy bones. This is important for you, and for developing baby. Vitamin D is also associated with many other beneficial fertility outcomes. Read more about this here>>

Deficiency is common, and supplementation is most likely necessary as requirements more than triple based on the type of surgery undertaken.

Most vitamin D will come from skin exposure to UV rays (sunlight), but you can obtain some vitamin D from foods like eggs, salmon and mushrooms which were soaked in the sunshine themselves.


Currently, you won’t find choline in bariatric multis, or in most prenatal supplements. But it is nutrient worth paying attention to.

Choline, like folate, is seen to be crucial for baby’s neural tube. With meat sometimes harder to eat post surgery, choline intake will be reduced also.

Dietary sources include liver, meat, legumes, fish and mushrooms.


Iodine is your thyroid’s best friend. It is essential for the synthesis of thyroid hormones T3 and T4. These hormones are responsible for metabolism and growth, amongst other crucial functions.

At present, guidelines do not make recommendations for an elevated intake beyond the national RDI. But, with reduced dietary intake, making a note to look at (and take!) recommended supplementation. Also including iodine rich foods in the diet for fertility after bariatric surgery is good move.


Most fats in the diet should come from monounsaturated and polyunsaturated fats. Let’s call these guys MUFAs and PUFAs.

Omega-3s sit in the PUFA group and contain essential fatty acids for good health, and for baby’s brain development. There is now also good evidence to suggest DHA and EPA in pregnancy reduce the risk of preterm delivery. Read more about omega-3s here >>

Evidence suggests omega-3 status is reduced post bariatric surgery. Adding oily fish like salmon, mackerel, trout or sardines to the diet at least twice a week is a good start to top up levels. Do chat to your health care team or dietitian prior to commencing any additional supplementation.


Iron requirements jump up from ~18mg per day for women, to 45-60mg per day for people post bariatric surgery.

This nutrient is one of the most common deficiencies seen in this cohort, especially for women who have their periods.

Here is where it gets tricky, iron requirements in pregnancy increase to accomodate additional blood volume, and placental transfer of iron from mum to baby for growth. Dietary iron may also be decreased related to reduced overall dietary intake post surgery. Also in pregnancy related to pregnancy induced nausea and vomiting (hello, morning sickness or HG).

Looking at dietary and supplemental iron in the 3-6 months prior TTC will ensure levels are topped for pregnancy.

Protein and overall diets

I have only scratched the surface here. There are a million and one other considerations from food relationships, micronutrient and macronutrient intake, food tolerances and post surgery symptoms, dietary preferences and forth. All requiring and deserving tailored advice.

Protein is the hot topic macronutrient post surgery. Dietary protein builds and maintains muscle in the body. I don’t need to explain why this is important for a developing baby. But for anyone who has undergone this surgery, I would guess it is for improved long-term health, and strong muscles are invaluable here.

A Mediterranean dietary pattern is suggested to be one of the healthiest in the world. It is the most researched diet to date and is considered incredibly beneficial for fertility. For fertility after bariatric surgery, a Med diet can be beneficial too. With a few tweaks to fill nutrient gaps to accomodate altered physiology and fertility needs.

As always, this is article is not intended as specific advice for you. But if you would like tailored nutrition guidance, book in>>