Abstract
Objective : To build a computer vision model that can
automatically detect sleeping position in the third trimester under
real-world conditions.
Design : This study used data from an ongoing observational
study and a previous cross-sectional study.
Setting : Participants’ homes.
Sample : Pregnant participants in the third trimester and their
bed partners.
Methods : Real-world overnight video recordings were collected
from an ongoing, Canada-wide, prospective, four-night, home sleep apnea
study and controlled-setting video recordings were used from a previous
study. Images were extracted from the videos and body positions were
annotated. Five-fold cross validation was used to train, validate, and
test a model using state-of-the-art deep convolutional neural networks.
Main Outcome Measures : Precision and recall of the model for
detecting thirteen pre-defined body positions.
Results : The dataset contained 39 pregnant participants, 13 bed
partners, 12,930 images, and 47,001 annotations. The model was trained
to detect pillows, twelve sleeping positions, and a sitting position in
both the pregnant person and their bed partner simultaneously. The model
significantly outperformed a previous similar model for the three most
commonly occurring natural sleeping positions in pregnant and
non-pregnant adults, with an 82-to-89% average probability of correctly
detecting them and a 15-to-19% chance of failing to detect them when
any one of them is present.
Conclusions : The model holds potential to solve yet unanswered
research and clinical questions regarding the relationship between
sleeping position and pregnancy outcomes.
Funding : Mitacs (Grant No. IT 26655)
Keywords : artificial intelligence, classification, deep
learning, detection, foetal growth, localization, real-world,
controlled-setting, small-for-gestational age, stillbirth, supine