Table 3.
Numbers of blood, urine, saliva, stool and placental samples per study site
| Sylhet-Bangladesh | Pemba-Tanzania | Karachi-Pakistan | Total | ||
|---|---|---|---|---|---|
| Sample type | Sample time | n/N (%) | n/N (%) | n/N (%) | n/N (%) |
| Maternal blooda | Enrolment (8 to <20 weeks) | 2999/3000 (100%) | 4501/4501 (100%) | 2500/2500 (100%) | 10000/10001 (100%) |
| Pregnancy visit 2 or pregnancy visit 3 | 2760/2958 (93.3%) | 4170/4423 (94.3%) | 2204/2427 (90.8%) | 9134/9808 (93.1%) | |
| Visit during postnatal period (42 days post-partum) | 2529/2731 (92.6%) | 4007/4473 (89.6%) | 2207/2330 (94.7%) | 8743/9534 (91.7%) | |
| Maternal urinea | Enrolment (8 to <20 weeks) | 3000/3000 (100%) | 4501/4501 (100%) | 2500/2500 (100%) | 10 001/10 001 (100%) |
| Pregnancy visit 2 or pregnancy visit 3 | 2767/2958 (93.5%) | 4170/4423 (94.3%) | 2204/2427 (90.8%) | 9141/9808 (93.2%) | |
| Visit during postnatal period (42 days post-partum) | 2534/2731 (92.8%) | 4007/4473 (89.6%) | 2205/2330 (94.6%) | 8746/9534 (91.7%) | |
| Faecesb | Maternal | 2581/3000 (86%) | 3869/4440 (86%) | 2201/2287 (96.2%) | 8651/9727 (88.9%) |
| Newborn | 2213/2858 (77.4%) | 3585/4366 (82.1%) | 1999/2205 (90.7%) | 7797/9429 (82.7%) | |
| Placentac | Placenta | 2532/2964 (85.4%) | 4095/4443 (92.2%) | 808/2325 (34.8%) | 7435/9732 (76.4%) |
| Cord bloodc | Fresh cord blood | 1488/2964 (50.2%) | 3674/4443 (82.7%) | 294/2325 (12.6%) | 5456/9732 (56.1%) |
| Clotted cord bloode | 567/2964 (19.1%) | 377/4443 (8.5%) | 517/2325 (22.2%) | 1461/9732 (15.0%) | |
| Saliva | Newbornd | 553/2858 (19.3%) | 206/4366 (4.7%) | 1413/2325 (60.8%) | 2172/9549 (22.7%) |
| Paternal | 2384/3000 (79.5%) | 3858/4501 (85.7%) | 2319/2500 (92.8%) | 8561/10 001 (85.6%) |
To calculate the proportion of maternal blood and urine samples collected during the pregnancy visits, the denominator is the total number of women still pregnant in the cohort at the time of the visit. For the maternal samples collected in the postnatal period, the denominator corresponds to the total number of women who had a stillbirth or live birth.
To calculate the proportion of newborn faeces collected, we included all babies born alive in the denominator.
To calculate the proportion of placenta and cord blood samples collected, we considered all pregnancies that ended in delivery as the denominator.
Collected only if cord blood could not be collected.
Collected only if fresh cord blood could not be collected.