Table 3.
Maternal and birth characteristics and available samples, in the pregnancy study
| Maternal characteristics at inclusion | Pregnancy cohort, n=538 | n included in calculations |
| Age (years) | 27 (23–33.5) | 532 |
| Height (cm) | 156 (152–159) | 535 |
| Weight (kg) | 55.6 (49.1–63.8) | 531 |
| Maternal first antenatal visit BMI (kg/m2) | 23 (20.5–26.1) | 528 |
| Systolic blood pressure (mm Hg) | 112 (12) | 535 |
| Diastolic blood pressure (mm Hg) | 71 (10) | 535 |
| Parity | 2 (1–4) | 538 |
| Ethnicity | 538 | |
| Sambaa | 198 | |
| Zigua | 173 | |
| Others* | 128 | |
| Education | 538 | |
| None or incomplete primary | 122 (22.7) | |
| Complete primary | 359 (66.7) | |
| Secondary or higher | 57 (10.6) | |
| Source of domestic water | 536 | |
| Private tap or bore hole | 25 (4.7) | |
| Public tap or bore hole | 369 (68.8) | |
| River/pool | 142 (26.4) | |
| Type of toilet facility | 536 | |
| Flush | 160 (29.9) | |
| Pit | 370 (69.0) | |
| None | 6 (1.1) | |
| Diabetes mellitus (known) | 2 (0.4) | 538 |
| HIV-seropositive | 17 (3.4%) | 500 |
| Pregnancy and birth characteristics | ||
| Gestational age (days) at enrolment | 63 (45–85) | 517† |
| Anaemia during pregnancy (Hb<11 g/dL) | 359 (66.7%) | 538 |
| Moderate-severe anaemia during pregnancy (Hb≤9 g/dL) | 85 (15.8%) | 538 |
| Severe anaemia during pregnancy (Hb≤8 g/dL) | 33 (6.3%) | 538 |
| Malaria during pregnancy | 185 (34.4%) | 538 |
| Early miscarriage (GA≤14 weeks) | 72 (13.4%) | 538 |
| Late miscarriage (GA>14 weeks, GA≤22 weeks) | 8‡ (1.5%) | 538 |
| Delivery | 427 | |
| At hospital | 369 (86.4%) | |
| At home | 45 (10.5%) | |
| At dispensary | 13 (3.0%) | |
| Caesarean section | 35 (8.2%) | 426 |
| Newborns delivered | 438 (410 singleton, 28 twins) | 427 women |
| Sex (boys) | 206 (48.5%) | 425 |
| Gestational age (days) at delivery (GA>22 weeks) | 280 (274–286) | 424§ |
| Preterm delivery (GA>22 and GA<37 weeks) | 27 (6.4%) | 424§ |
| Birth weight (g)¶ | 3016 (486) | 379 |
| Low birth weight≤2500 g¶ | 39 (10.3%) | 379 |
| Stillbirth# | 12 | 435 |
| Neonatal death (before 28 days)¶ | 13 | 423 |
| Perinatal mortality rate (stillbirth+first 7 days of life)¶ | 53/1000 | 435 |
| Neonatal anthropometry after 28 days of life | 400 | 410 |
| Paternal follow-up | 113 | |
| Blood samples, biopsies and stereology | ||
| Inclusion | 534 | 538 |
| GA 11–14 weeks | 259 | 276 |
| AV 2 (GA 20 weeks) | 389 | 391 |
| AV 3 (GA 26 weeks) | 391 | 393 |
| AV 4 (GA 32 weeks) | 404 | 404 |
| AV 5 (GA 37 weeks) | 367 | 370 |
| Delivery | 410 | 427 |
| Cord blood** | 366 | 438 |
| Placental epigenetic samples** | 395 | 427 |
| Placental stereology samples‡ | 393 | 427 |
Data are presented as mean (SD), median (IQR) or n (%).
*Includes: all other tribe groups including tribes with <10% prevalence.
†Among the 538 women 21 had a positive UPT on inclusion into the pregnancy study but had a miscarriage before GA was estimated by ultrasound evaluation.
‡Three of these participants had a very late miscarriage with complete delivery data collected, and are therefore included in the total number of 427 deliveries.
§Three late miscarriages are excluded.
¶Includes: singleton, live births, no major malformation, GA >22 weeks.
**Includes: all neonates (singleton + twins).
AV, antenatal visit; BMI, body mass index; GA, gestational age; Hb, haemoglobin.