Are early first trimester weights valid proxies for preconception weight?

An accurate estimate of preconception weight is necessary for providing a gestational weight gain range based on the Institute of Medicine’s guidelines; however, an accurate and proximal preconception weight is not available for most women. We examined the validity of first trimester weights for estimating preconception body mass index category. Under identical measurement conditions, preconception weight and two first trimester weights (i.e.,...