How does pregnancy affect risk of stroke in older, younger women?

October 24, 2016

Younger pregnant women, including the postpartum period up to six weeks after delivery, appeared to be at increased risk of stroke compared with their nonpregnant counterparts, and that increased stroke risk was not associated with older pregnant women, according to a new article published online by JAMA Neurology.

Eliza C. Miller, M.D., of Columbia University, New York, and coauthors used data on all admissions in the state of New York from 2003 to 2012 to determine age-specific incidence risk ratios for pregnancy-associated stroke (PAS) compared with nonpregnancy-associated stroke (NPAS).

There were 19,146 women hospitalized with stroke during the study period and 797 (4.2 percent) of the women were pregnant or postpartum.

The authors report the incidence of PAS in women 12 to 24 years old was 14 events per 100,000 pregnant/postpartum women compared with a NPAS incidence of 6.4 per 100,000 nonpregnant women. In women 25 to 34, the PAS incidence was 21.2 per 100,000 pregnant women and NPAS incidence was 13.5 per 100,000 nonpregnant women.

In older women 35 to 44, PAS incidence was 33 per 100,000 pregnant women and NPAS incidence was 31 per 100,000 nonpregnant women. In women 45 to 55, PAS incidence was 46.9 per 100,000 pregnant women compared with NPAS incidence of 73.7 per 100,000 nonpregnant women.

Although older pregnant women had higher rates of stroke in pregnancy than younger , their risk of stroke was similar to women of their own age who were not pregnant. But in women under 35, pregnancy increased the risk of stroke, more than doubling it in the youngest group, the authors report.

PAS accounted for 15 percent of strokes in women 12 to 24; 20 percent of strokes in women 25 to 34; 5 percent of strokes in women 35 to 44; and 0.05 percent of strokes in women 45 to 55, according to the results.

Women with PAS were less likely than women with NPAS to have vascular risk factors, diabetes and active smoking. Death was also lower among women with PAS compared with NPAS. The authors note different underlying stroke mechanisms may factor into why younger women had higher stroke risk during pregnancy.

Study limitations include billing data that lack specificity, especially in regard to PAS.

"In our sample of all women aged 12 to 55 years hospitalized with stroke in New York State from 2003 to 2012, younger pregnant and postpartum women - but not older women - were at increased risk of stroke compared with their nonpregnant contemporaries. These results have potential implications for research aimed at better characterizing and preventing PAS and clinically in terms of counseling patients. Although have an increased risk of many pregnancy complications, a higher risk of stroke may not be one of them. Our results should be interpreted with caution and regarded primarily as hypothesis generating; more research is needed to investigate why younger may have an increased risk of PAS," the study concludes.

Explore further: Study explores link between weight and stroke risk in women

More information: JAMA Neurol. Published online October 24, 2016. DOI: 10.1001/jamaneurol.2016.3774

Related Stories

Study explores link between weight and stroke risk in women

September 8, 2016
(HealthDay)—Excess weight may put women at increased risk for ischemic stroke, but at lower risk for hemorrhagic stroke, according to research published online Sept. 7 in Neurology.

Pregnancy in older age increases stroke, heart attack risk years later

February 17, 2016
Women who become pregnant at age 40 or older face a greater risk of stroke and heart attack later in life than women who become pregnant at a younger age, according to research presented at the American Stroke Association's ...

Hospitalizations in pregnancy, delivery stable for HIV-infected

October 10, 2016
(HealthDay)—From 2004 to 2011 there was no increase in the number of hospitalizations during pregnancy and delivery for HIV-infected women, according to a study published in the October issue of the American Journal of ...

Rate of stroke increasing among women during, soon after pregnancy

July 29, 2011
The stroke rate for pregnant women and those who recently gave birth increased alarmingly over the past dozen years, according to research reported in Stroke: Journal of the American Heart Association.

No difference in post-op complications for pregnant women undergoing general surgery

May 13, 2015
Pregnant women who undergo general surgical procedures appear to have no significant difference in postoperative complications compared with women who are not pregnant, according to a report published online by JAMA Surgery.

Calcium supplements linked to dementia risk in women with certain health conditions

August 17, 2016
According to a new study, calcium supplements may be associated with an increased risk of dementia in older women who have had a stroke or other signs of cerebrovascular disease. The research is published in the August 17, ...

Recommended for you

Study finds graspable objects grab attention more than images of objects do

December 15, 2017
Does having the potential to act upon an object have a unique influence on behavior and brain responses to the object? That is the question Jacqueline Snow, assistant professor of psychology at the University of Nevada, Reno, ...

Little understood cell helps mice see color

December 14, 2017
Researchers at the University of Colorado Anschutz Medical Campus have discovered that color vision in mice is far more complex than originally thought, opening the door to experiments that could potentially lead to new treatments ...

Scientists chart how brain signals connect to neurons

December 14, 2017
Scientists at Johns Hopkins have used supercomputers to create an atomic scale map that tracks how the signaling chemical glutamate binds to a neuron in the brain. The findings, say the scientists, shed light on the dynamic ...

Activating MSc glutamatergic neurons found to cause mice to eat less

December 13, 2017
(Medical Xpress)—A trio of researchers working at the State University of New York has found that artificially stimulating neurons that exist in the medial septal complex in mouse brains caused test mice to eat less. In ...

Gene mutation causes low sensitivity to pain

December 13, 2017
A UCL-led research team has identified a rare mutation that causes one family to have unusually low sensitivity to pain.

Scientists discover blood sample detection method for multiple sclerosis

December 13, 2017
A method for quickly detecting signs of multiple sclerosis has been developed by a University of Huddersfield research team.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.