“Normal” doubling time
| Beta-hCG | LMP (DPO) * | Doubling time |
|---|---|---|
| < 1200 | < 5 weeks (21 dpo) | 2-3 days (48-72 hours) |
| 1200-6000 | 5-6 weeks (21-28 dpo) | 3-4 days (72-96 hours) |
| > 6000 | > 6 weeks (28 dpo) | more than 4 days (96 hours) |
LMP – last menstrual period.
DPO – days past ovulation (post-ovulation).
High levels of hCG
Extremely high levels of hCG may suggest multiple pregnancy (twins, triplets, or more).
Low levels of hCG
A low level of hCG may mean that ovulation occurred later than expected, if the HCG level is rising (doubling) adequately.