Figure 1.
Type and number of urine samples analyzed in this study from 188 pregnancies. Theoretically, if all mothers were fully compliant with our sampling protocol (three FMVs and one 24-hour sample for each of the 2nd and 3rd trimesters), the total number of samples available for this present study should be 1,504. After selecting the first FMV as an individual sample and pooling the remaining samples, a total number of 752 samples should remain for analysis: 376 FMVs as an individual sample and 376 pools with 3 composites. Although all mothers were asked to collect four samples per trimester, many did not. In some cases, samples provided by mothers as the 2nd trimester sample were later determined as the 3rd trimester sample or vice versa. In other cases, mothers collected more samples than necessary. Thus, the number of samples included in each of the 198 pools varied based on the number of samples each woman collected.