Figure 4
Derived eGFR from serum creatinine SCr hyperfiltration and RI construction. (a) Two values for eGFR calculation. Pregnancy-related hyperfiltration can be inferred from decreased SCr values compared to non-pregnant states (Eq. (3), overall hyperfiltration ratio). However, since SCr based on GW exhibited curvilinearity, a correction factor (kgw) was applied for each GW in the overall hyperfiltration ratio. (b) Derived eGFR from original SCr measurement. The overall hyperfiltration ratio and the kgw were substantiated for deriving eGFR from SCr measurements, and the final calculation process is defined as gestational eGFR formula (Eq. 6). (c) Best degrees for eGFR RI. Similar to the process of constructing SCr RI, the best degrees of the upper and lower limit for eGFR RI were explored a thousand times, respectively, and were both 4. (d) Confirmed optimal polynomial regression curves for the upper and lower limits of eGFR. The pre-implantation period (0–3 GW, which is 1 GP) was also excluded from the regression analysis.
