What are some risk factors in miscarriage?

Despite all the medical advancements in the last century, miscarriages are still very common and feared by many pregnant women. In 2005, Health Canada recorded a fetal loss rate of  2 out of 1000 in women aged 25 to 29. 

When considering miscarriages there are certain lifestyle factors we can modify to help decrease our risk. In this article, we will review the impacts of caffeine and alcohol on pregnancies.


Some studies have associated coffee consumption during pregnancy with miscarriages. Researchers have found a higher risk of miscarriages with higher consumption of caffeine especially caffeine obtained from coffee rather than tea or chocolate.

Another study found that miscarriages were significantly higher in women who drank caffeine prior to conception and during their first trimester. Keep in mind that it takes a newborn about 32 to 140 hours to eliminate only half the amount of caffeine in its system, whereas it takes a healthy adult only 2.5 to 4.5 hours.


In a study conducted on 252 couples registered for either In Vitro fertilization (IVF) or Gamete intrafallopian transfer (GIFT) it was found that women who consumed alcohol the month prior to their treatment had a 13% decrease in eggs collected, were 2.86 times less likely to conceive and had a 2.21 increased chance of miscarrying.

In addition, this study revealed that consumption of alcohol in the male partner also had a significant dose-dependent impact. This means the more they drank the less likely they were able to conceive, and the more likely their female partner would miscarry.

Men who drank the month prior to the fertility treatments were 2.26 times less likely to conceive and had a 2.70 increased chance of miscarrying.

In summary

Caffeine consumption by women trying to conceive or during their first trimester, as well as alcohol consumption in both female and male partners prior to IVF or GIFT, can have a significant impact on the risk of miscarrying.

Women who are underweight or overweight; who lift 20 kg or more on a daily basis; or who work night shifts also have a higher miscarriage risk.

History of contraception (oral or IUD), abortion or intercourse in early pregnancy have NOT been found to cause miscarriages. 

As you may already know, not all miscarriage risk factors are lifestyle-based. If you have experienced two or more miscarriages you should be assessed by a healthcare practitioner. Conditions such as PCOS, Hashimoto’s thyroiditis, luteal phase defect, hyperhomocysteinemia, endometriosis and celiac disease can all cause recurrent miscarriages.

As Naturopathic Doctors we are in a unique position to use laboratory assessment to measure  your risk of miscarriage and use natural interventions and dietary advice to lower the risk of miscarriage.

Written by

Dr. Natacha Montpellier, B.Sc. ND.


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