 ### Description

Placentas show a distribution in size and weight with increases seen with increasing gestational age.

 week gestation placenta weight low mean placenta weight placenta weight high 23 116.6 126 135.4 24 151.6 158.1 164.6 25 144.4 158.3 172.2 26 173.2 187.5 201.8 27 146.7 151.5 156.3 28 188.9 213.6 238.3 29 208 220.4 232.8 30 241.3 260.3 279.4 31 265 286.3 307.7 32 285.2 306.6 328 33 280.4 292.2 304.1 34 320.1 333 345.9 35 337.8 353.2 368.6 36 374.5 383.2 391.9 37 394.7 405.6 416.5 38 401.5 406.9 412.3 39 421.4 425.7 430 40 433.7 437.1 440.5 41 443.5 450.7 457.9 42 454.7 465 475.3 43 480.1 489 497.9

Initial line approximations:

placenta weight low =

= (18.98388 * (week gestation)) - 328.224

placenta weight high =

= (18.314558 * (week gestation)) - 282.6047

week gestation for low weight placentas =

= ((0.0000104 * ((placental weight) ^2)) + (0.0457037 * (placental weight)) + 18.303052

week gestation for mean weight placentas =

= ((0.0000264 * ((placental weight) ^2)) + (0.0365859 * (placental weight)) + 18.775538

week gestation for high weight placentas =

= ((0.0000436 * ((placental weight) ^2)) + (0.0260057 * (placental weight)) + 19.566584

Subsequent line approximations:

 Line fetal weight = low, 23 to 34 weeks (0.6631 * ((weeks)^2)) - (19.81 * (weeks)) + 228.1 low, 34 to 43 weeks (-1.305 * ((weeks)^2)) + (115.9 * (weeks)) - 2111 high 23 to 34 weeks (0.2257 * ((weeks)^2)) + (6.56 * (weeks)) - 134 high, 34 to 43 weeks (-0.5576 * ((weeks)^2)) + (57.3 * (weeks)) - 953.2