| Doubling Time | Number of Pregnancies in this range |
|---|---|
| 11 - 14 hours | (3) |
| 14 - 18 hours | (2) |
| 18 - 22 hours | (16) |
| 22 - 28 hours | (131) |
| 28 - 36 hours | (855) |
| 36 - 45 hours | (1466) |
| 45 - 56 hours | (622) |
| 56 - 71 hours | (144) |
| 71 - 89 hours | (26) |
| 89 - 112 hours | (4) |
| 112 - 141 hours | (3) |
| 141 - 178 hours | (2) |