Best greetings and hope you are doing well. Your question itself indicates great shortage in understanding the statistical medicine application and the software which calculates the required parameters you have chosen in your study to evaluate prediction of preeclampsia.
I would suggest that you attend two courses intensively; first in medical statistics as guided by up to date software, while the second course in excel, statistical software and related affairs.
In order to evaluate the method you have chosen in your study as predictor of preeclampsia you should have a wide insight into the methods used in predictions in statistics for example ROC curve.
Then after you collect your data you analyze them with at least 30 free of charge software in statistics available nowadays in the web. You can chose the one much suits your taste.
otherwise you will jump from one idea to other without gaining any results. and please always remember JUMPING or OVER upstairs always rewards bad for your future.