Does Inflammatory Bowel Disease impact fertility?
Does having Inflammatory Bowel Disease impact fertility?
It is understandable that if you have Inflammatory Bowel Disease you may be hesitant about starting a family. Our concerns around pregnancy can vary from our ability to conceive, impact of medications on the baby in the womb or impact of pregnancy on our disease. As a result of these concerns, both males and females with IBD are less likely to have children than people without IBD. One study concluded 44% of women and 50% of men of child bearing age with Crohn’s disease were childless through choice (1), compared with less than 20% of the general population.
I am thinking of starting a family, what should I do?
Research shows us that having Inflammatory Bowel Disease alone does not decrease fertility levels. However, surgery as a result of IBD complications can decrease fertility, particularly if it was close in proximity to reproductive organs (2). Each case will be individual and therefore it is important to talk to your consultant gastroenterologist and IBD team if you are considering starting a family. Likewise, whilst most medications are not considered to be harmful to the baby, there are some which are not recommended and this should be discussed with your doctor.
Should I wait until I am in remission?
In order to avoid being at an increased risk of pregnancy and birth complications, it is recommended that women with IBD are in stable remission for at least 6 months before trying to conceive. Due to the proximity of the gut to reproductive organs, inflammation may also spread to the ovaries and womb, so getting inflammation under control is a logical first step.
What are the nutritional considerations when trying to get pregnant with IBD?
Overall nutritional status is important for both males and females when trying to get pregnant. Deficiencies in nutrients can have an impact on the quality of the egg and sperm we produce, as well as the womb lining to support implantation of the egg and development of the foetus. Having IBD can often impact our nutritional status and increase the likelihood that we are deficient in certain nutrients. It is therefore important to address any of these issues a few months before trying to conceive.
Healthy Weight
It is recommended that a BMI (calculated as your weight divided by your height) within the range of 19–30 is optimum for fertility (3), which can be a challenge for people with IBD to maintain. If you are not ovulating regularly, then bringing your BMI within this range may help regulate your periods and increase the chance of conception. When trying to gain weight consuming healthy calorie dense foods such as avocados, nut butters or adding olive oil to your food may be a good way to increase your calorie intake, as long as they are tolerated.
Vitamins and Minerals
Whilst a balanced diet full of fruit, vegetables and wholegrains should typically give us all the nutrients we need for fertility, people with IBD are faced with unique challenges making this harder to achieve. Circulating blood levels of key nutrients such as vitamin B12, vitamin D, iron and calcium may be factors in successful pregnancies and these are known to be lower in people with IBD (4). The location and severity of inflammation, as well as medications, can have an influence on how well we are able to absorb these vitamins.
Folic Acid/Folate
To help prevent neural tube defects it is recommended that all women take a 400ug supplement of folic acid whilst trying to conceive and for the first 12 weeks of pregnancy (5). As folate is mainly absorbed in the upper part of the small intestine, a higher level may be recommended for people with small bowel Crohn’s disease, people who have had a resection of their bowels and patients taking the medication Sulfasalazine. Folate can also be obtained naturally from the diet by eating foods such as broccoli, kidney beans, leafy greens and eggs.
Vitamin B12
Vitamin B12 is absorbed in the last part of the small intestine, leading to deficiencies in people with Crohn’s disease of the terminal ileum and people who have had resections of the small intestine (4). Having low levels of vitamin B12 has been associated with infertility in both men and women (6). It is therefore important to correct any deficiency in either partner and ensure you are consuming plenty of vitamin B12 rich foods such as beef, fish, chicken, dairy, eggs, fortified breakfast cereals or yeast extract.
Vitamin D
A vitamin D supplement of 10mg a day is recommended for all adults living in the UK, including those trying to conceive (7). Only a small amount of the vitamin D we require comes from our diet, with oily fish and eggs being two of the main sources. Even though we produce vitamin D when exposed to sunlight, we often do not get enough exposure, particularly in winter. People with IBD have been found to be significantly more deficient in vitamin D than the rest of the population. Most cells in the human body have vitamin D receptors which includes the reproductive organs and immune system. Studies have shown low vitamin D levels in males are associated with lower sperm quality (8).
Iron
Iron has been found to reduce infertility by supporting ovulation, so if you are experiencing difficulties in conceiving then check for an Iron deficiency. Iron deficiency anaemia has been found in a third of patients with IBD, caused by a combination of intestinal bleeding, poor absorption through the gut due to inflammation and in Crohn’s disease due to high levels of iron consuming bacteria colonising the gut (9). Oral iron supplementation is available but can often exasperate digestive symptoms, making injections a preferrable option to correct levels. You can also get good sources of iron from your diet by eating red meat, chicken, fish and eggs, which all contain an easily absorbed type of iron called heme iron. Other sources of non-heme iron found in spinach, oats, chickpeas, lentils and broccoli are not as easily absorbed, but can still contribute towards your overall iron intake.
Calcium
Calcium has been found to be important for the quality of sperm in men (10) and therefore something to consider if experiencing difficulties with conception. Some commonly used treatments for the symptoms of IBD, such as oral steroids, can reduce the absorption of calcium significantly. Long term use of these drugs is known to affect bone health, so taking a calcium supplement is often recommended. As vitamin D helps with the absorption of calcium, it is also important to take vitamin D supplements at the same time.
If you suffer from IBD you may find that foods which contain a good source of calcium, such as milk and other dairy products, can trigger symptoms possibly due to their lactose content. However, good sources of calcium are available which do not contain lactose, such as fortified milk alternatives, turnip, kale, kidney beans, baked beans and dried figs. Hard cheeses such as cheddar cheese and parmesan are also good sources of calcium, whilst having very low levels of lactose.
Fruit and Vegetables
Although fruits and vegetables are a great source of the micro-nutrients required for pregnancy, if you have IBD it may be difficult to tolerate the fibre in these foods. However, this does not mean that you need to miss out on all fruit and vegetables, peeling and deseeding and then cooking well can help to break down the fibre making it easier to digest. Alternatively, blending fruit and vegetables into purees, soups or juices are all good ways to make fruit and vegetables more tolerable.
Takeaways
having IBD does not decrease fertility in people who have not had surgery
starting a family should be discussed with your IBD team, to enable them to check medications and nutrient deficiencies
it is best to have inflammation under control before conceiving to avoid complications
aim to achieve a healthy weight to regulate periods
nutritional deficiencies in males and females can make it harder to conceive and have a healthy pregnancy
it is recommended to correct any deficiencies at least 3 months before trying to conceive.
If you would like help and support with your IBD and what dietary and lifestyle changes would be appropriate for you, please get in touch with me. You can book a free call, where I can get to know you, your journey, your struggles, your life, and we can chat about the best route forward for you. You can also ask any questions you have about working with me.
This article was written by Helen Morris (MSc, ANutr) who is our wonderful intern at The NALM Clinic. She's passionate about IBD nutrition research and sharing evidence based IBD nutrition information having lived with Crohn's Disease since 2018.
References
Tavernier, N. et al (2013), Systematic review: fertility in non‐surgically treated inflammatory bowel disease. Alimentary Pharmacology & Therapeutics, 38: 847-853. https://doi.org/10.1111/apt.12478
Mountifield, R. et al (2009) Fear and Fertility in Inflammatory Bowel Disease: A Mismatch of Perception and Reality Affects Family Planning Decisions, Inflammatory Bowel Diseases, 15 (5), 720–725, https://doi.org/10.1002/ibd.20839
https://www.nhs.uk/conditions/infertility/
Weisshof R (2015). Micronutrient deficiencies in inflammatory bowel disease. Curr Opin Clin Nutr Metab Care. Nov;18(6):576-81. doi: 10.1097/MCO.0000000000000226. PMID: 26418823.
https://www.nhs.uk/pregnancy/keeping-well/vitamins-supplements-and-nutrition/
Bennett M. (2001) Vitamin B12 deficiency, infertility and recurrent fetal loss. J Reprod Med. Mar;46(3):209-12. PMID: 11304860.
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
Rehman, R. (2018) Association Between Vitamin D, Reproductive Hormones and Sperm Parameters in Infertile Male Subjects. https://doi.org/10.3389/fendo.2018.00607
Stein, J (2010). Diagnosis and management of iron deficiency anaemia in patients with IBD. Nat Rev Gastroenterol Hepatol, 7, 599-610
Hong CY, Chiang BN, Turner P. Calcium ion is the key regulator of human sperm function. Lancet. 1984 Dec 22;2(8417-8418):1449-51. doi: 10.1016/s0140-6736(84)91634-9. PMID: 6151055.