***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: We found two studies involving 4993 participants. The methodological quality of the trials was good. Both studies included women at low risk for hypertensive disorders, with Doppler ultrasound of the uterine arteries performed in the second trimester of pregnancy. In both studies, pathological finding of uterine arteries was followed by low-dose aspirin administration. We identified no difference in short-term maternal and fetal clinical outcomes. We identified no randomised studies assessing the utero-placental vessels in the first trimester or in women at high risk for hypertensive disorders. Present evidence failed to show any benefit to either the baby or the mother when utero-placental Doppler ultrasound was used in the second trimester of pregnancy in women at low risk for hypertensive disorders. Nevertheless, this evidence cannot be considered conclusive with only two studies included. There were no randomised studies in the first trimester, or in women at high risk. More research is needed to investigate whether the use of utero-placental Doppler ultrasound may improve pregnancy outcome.
Output:

It is used in pregnancy to study blood circulation in the baby, the mother's uterus and the placenta. If abnormal blood circulation is identified, then it is possible that medical interventions might improve outcomes. We set out to assess the value of using Doppler ultrasound of the mother's uterus or placenta (utero-placental Doppler ultrasound) as a screening tool. Other reviews have looked at the use of Doppler ultrasound on the babies' vessels (fetal and umbilical Doppler ultrasound). We also choose to look at women with low-risk and high-risk pregnancies, and in their first or second trimesters. This screening offers a potential for benefit, but also a possibility of unnecessary interventions and adverse effects. The review of randomised controlled trials of routine Doppler ultrasound of the uterus or placenta identified two studies involving 4993 women. All the women were in the second trimester of pregnancy and at low risk for hypertensive disorders. The studies were of good quality but small in size. We identified no improvements for the baby or the mother. However, more data would be needed to show whether maternal Doppler is effective, or not, for improving outcomes. We did not find any studies in the first trimester of pregnancy or in women at risk of high blood pressure disorders. More research is needed on this important aspect of care.