(RxWiki News) Being sick while pregnant certainly isn't fun. Having the flu while pregnant is even worse. But being down with the flu during pregnancy might be linked to longer term concerns, too.
A recent study found that children whose mothers had the flu while pregnant had an almost four times higher risk for bipolar disorder.
This study's findings do not mean that getting the flu during pregnancy will cause psychiatric problems for a child.
This probable link does provide another reason for pregnant women to take precautions to protect themselves from the flu, such as getting the flu vaccine and avoiding sick individuals, the researchers said.
"Talk to your OB/GYN about the flu shot."
The study, led by Raveen Parboosing, MMed, of the Department of Virology, at the University of KwaZulu-Natal's Albert Luthuli Central Hospital in South Africa, looked at whether a woman's having the flu while she was pregnant was linked to bipolar disorder in her child.
The researchers used data from a large group of pregnant women who were treated in the Kaiser Permanente Medical Care Plan in the Northern California Region from 1959 to 1966.
First, the researchers identified all the women who had been treated for the flu while pregnant in the group. Then they identified all the possible cases of bipolar disorder among their children using questionnaires and medical records.
Out of 214 possible cases, 92 children were confirmed to have bipolar disorder, based on interviews and the diagnosis of a group of clinicians.
The researchers included patients with four types of bipolar disorder: bipolar I, bipolar II, bipolar not otherwise specified or bipolar with psychotic features.
These bipolar participants were compared to 722 other participants without bipolar disorder who were matched on the basis of same birth dates, sex and geographical location.
The researchers found that children whose mothers had the flu during pregnancy had almost four times the risk of having bipolar disorder.
This link remained after the researchers made adjustments to their analysis to account for differences among the mothers' age, race/ethnicity, educational level, psychiatric history and the pregnancy week when she gave birth.
Past studies have found possible links between schizophrenia and a child's exposure to the flu while in the womb.
However, these studies can be difficult to interpret because it is often not possible to consider all the possible underlying differences among the pregnant women.
For example, some research has found that women with psychiatric disorders are also more likely to get the flu, and it may not be possible to completely account for this risk possibility in a group of women.
It is also possible that some women in the study had the flu while pregnant, but it was not diagnosed or they did not see a doctor, so cases might have been missed.
Similarly, some of those with bipolar disorder may not have been diagnosed, or diagnosed yet, since the disease is often diagnosed in a person's early 20s, and some of the children are not yet that old.
The authors noted that preventative measures for flu may include "pre-pregnancy vaccination and avoidance of individuals who have overt symptoms of respiratory tract infection."
The study was published May 8 in the journal JAMA Psychiatry. The research was funded by the National Institute of Mental Health and the National Institute on Child Health and Development. The authors reported no conflicts of interest.