Sample collection schedule for PREG and the MDP extension
| Measure | PREG time points (weeks gestation) | MDP time points | |||||
| 0–15 | 10–25 | 20–40 | 37–42 | Birth | 6 weeks | 6–12 months | |
| Maternal data* | |||||||
| SEDH survey | 232 | – | – | – | – | – | – |
| PSE survey | 232 | 185 | 192 | 147 | – | 105 | 57† |
| DNAm | 234 | 190 | 183 | 161 | – | 107 | 55† |
| Gene expression | – | – | – | 159 | – | – | – |
| GWAS‡ | 234 | – | – | – | – | – | – |
| Telomere length | 234 | – | – | – | – | – | – |
| Micronuclei | 234 | – | – | – | – | – | – |
| NIfETy§ | 139 | – | – | – | – | – | – |
| Child data (newborn)¶ | |||||||
| DNAm | – | – | – | – | 136 | – | – |
| Gene expression | – | – | – | – | 87 | – | – |
| Telomere length | – | – | – | – | 136 | – | – |
The numbers shown in the table represent the number of samples collected. Only samples from participants who met all birth inclusion criteria will be processed.
*DNAm, gene expression, GWAS, telomere length and micronuclei measurements using peripheral blood.
†Approximately half of the participants who continued to the MDP extension aged out before the second postpartum visit because funding was not obtained until 2014.
‡Intended to identify methylation quantitative trait loci.
§NIfETy ratings were completed either during pregnancy or within 1 year of birth.
¶DNAm, gene expression and telomere length measured in umbilical cord blood.
DNAm, DNA methylation; GWAS, genome-wide association study; MDP, major depression in the peripartum; NIfETy, Neighbourhood Inventory for Environmental Typology; PSE, pregnancy-specific environment; SEDH, social and environmental determinants of health.