American Journal Obstetrics And Gynaecology

American Journal Obstetrics And Gynaecology

American Journal Obstetrics And Gynaecology

A case study published by the journal Emerging Infectious Diseases suggests a possible link between exposure to seasonal flu and second semester miscarriage. The authors of the study recommend further work be undertaken to establish whether the flu virus poses a significant risk to women in the early stages of pregnancy.

Causes of miscarriage

Between 15% and 20% of pregnancies end in miscarriage, around half of which are the result of chromosomal defects (Goddjin and Leschot, 2000). Many other cases of miscarriage therefore have unexplained causes, but may be due to maternal inflammatory responses to infection. There are a number of factors which are associated with increased risk of miscarriage including age, obesity, smoking, and some medical conditions such as diabetes, high blood pressure or thyroid problems.

Flu and pregnancy

There were early reports of increased illness and death relating to pregnant women during the influenza A pandemic of 2009-2010 (swine flu). Siston et al reported that pregnant women contributed 5% of all deaths from influenza A(H1N1) in the US during the flu pandemic, indicating that pregnant women have a disproportionately high risk of complications associated with flu. There have also been reports of higher miscarriage rates during previous influenza pandemics, including the Asian flu outbreak of 1957-1958 (Hardy et al, 1961). However, a firm link between seasonal flu and increased miscarriage risk has been very difficult to demonstrate due to the high incidence of both flu and miscarriage itself.