Comment Authors: Diana Aguiar de Sousa, Department of Neurology, Hospital de Santa Maria, University of Lisbon, Portugal

Original Article: Aarnio K, Gissler M, Grittner U et al. 2017. Outcome of pregnancies and deliveries before and after ischaemic stroke. European Stroke Journal; Online first: doi: 10.1177/2396987317723795

The incidence of ischemic stroke at younger ages has increased during the past decades, including in women at childbearing ages. Pregnancy is a well-known risk factor for stroke and history of pre-eclampsia or gestational diabetes mellitus has been associated with increased risk of stroke. However, previous literature regarding the reproductive health of patients with ischemic stroke is limited and has failed to distinguish risks of pregnancy-related complications before and after ischemic stroke.

In this paper, Aarnio and colleagues aimed to quantify the incidence of pregnancy and delivery related complications before and after ischemic stroke, compared with stroke-free controls.

The authors used data from the Helsinki Young Stroke Registry, including 1008 consecutive patients who had a first-ever ischemic stroke between 1994 and 2007, and the Medical Birth Register, in which all births occurring in Finland between 1987 and 2014 were recorded.

380 women from the Helsinki Young Stroke Registry had any pregnancy recorded in the Medical Birth Register and a total of 152 women were included, as well as 608 control mothers matched by age, parity, year of delivery, residential area and number of newborns in the last pregnancy. The endpoints were: pre-eclampsia and/or eclampsia; placental abruption; gestational diabetes mellitus; hospital admission during pregnancy; preterm birth and/or low birth weight; small-for-gestational age; Apgar at 1 min ≤ 6; child not at home one week after the delivery; perinatal death; and a composite outcome including all prior outcomes as a count outcome. The outcomes of pregnancies and deliveries before and after stroke were compared separately. Only singleton pregnancies were included in the main analysis.

124 mothers had 207 pregnancies before the impending ischemic stroke and 45 mothers had 68 pregnancies after suffering the ischemic stroke. There were 17 mothers with both pre-stroke and post-stroke pregnancies. The index ischemic stroke was related with pregnancy in 8 mothers. The median time from the last birth of a child to stroke was six years.

Notably, mothers who had suffered an ischemic stroke had more induced abortions, miscarriages, caesarean sections and assistive reproductive technologies at first pregnancy after stroke.

After adjustment, the incidence rate ratio for the composite outcome was 1.43 (p=0.05) for mothers with stroke, compared with matched control mothers before stroke. Perinatal death and the incidence of hospital admissions during pregnancy were also slightly higher compared with the control mothers, particularly in the poststroke setting.

Despite the small numbers and possible detection bias associated with the use of registries, the authors suggest these associations could be linked to common risk factors, such as smoking, or common pathologies, as uteroplacental ischaemia. Larger studies are needed to confirm whether mothers with ischemic stroke are at increased risk for morbidity during pregnancy or perinatal death.

The original article “Outcome of pregnancies and deliveries before and after ischaemic stroke” is available in the Online First section of the European Stroke Journal.

Aarnio K, Gissler M, Grittner U et al. 2017. Outcome of pregnancies and deliveries before and after ischaemic stroke. European Stroke Journal. 2017
doi: 10.1177/2396987317723795