Diet and Fertility

cherries and peaches with vegetables


Should you make changes to your diet when trying to conceive?

At Merrion Fertility Clinic, we recommend a healthy BMI of between 19 – 30, which is associated with the best chance of conceiving and also of having a healthy pregnancy. Women who are not ovulating, or have no periods at all, may find that restoring their weight to the optimal range can restore ovulation & correct disturbances in their menstrual cycle. Also, in pregnancy, being significantly underweight or over weight increases risks for both mother and baby.

Patients of Merrion Fertility Clinic who are having trouble maintaining an optimal BMI can request a referral to attend Sinead Curran.  Sinead is a senior dietician in women’s health at the National Maternity Hospital and provides private sessions by appointment.


Please see below for tips on nutrition, weight management and supplements for couples who are trying to conceive.

  • Optimise your health overall- nutrition is part of that
  • Sort out any chronic condition such as diabetes, coeliac disease, mental health, thyroid illness with your doctor/ MDT well in advance
  • Get your weight right
    • Normal BMI 18.5-25kg/m2
    • Underweight? Gaining weight improves hormonal function and reduces risk of miscarriage
    • Overweight? Losing 7-10% of your current weight improves your fertility
    • Don’t ‘go too soon’- address weight at least 3-6 months before you plan to be pregnant
  • Take folic acid 400mcg tablet daily
  • Address anaemia & improve iron stores with diet
  •  A multivitamin may be useful as well as a healthy diet, but not instead of dietary changes
  •  Don’t smoke, drink alcohol excessively or use drugs
  •  Cut down on caffeine
  •  Check vaccinations & prescription drugs

What is a Balanced Diet for Preconception?

For Him & Her:

  • Starchy carbohydrate for energy- about half your plate (or 2 handfuls) at each meal- more if very active
  • Choose wholegrains, reduce simple sugar
  • Lots of vegetables- all kinds, for fibre, vitamins and minerals
  • Moderate protein x 2 a day- meat, chicken, fish & seafood are iron rich and contain zinc and oily fish are also rich in omega 3 fatty acids & vitamin D; red meat 3 times a week; oily fish once a week.
  • Use vegetable protein more often- beans, lentils, chickpeas e.g. meat free once a week
  • Include some fruit for vitamins & fibre & yogurts, cheese, milk for calcium, vitamin D
  • Include foods like nuts, seeds, olives, avocado for the healthy fats & oils and antioxidants like selenium

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