Table 2  Maternal outcome classified according to birth weight.

Variable	4 000 – 4 499 g	4 500 – 4 999 g	≥ 5 000 g	all	p
(* n ):  Number of missing data for the variable **  Fisherʼs exact test (instead of χ 2 test, if expected n of a group < 5) ***  Grade III/IV perineal laceration, bleeding > 500 ml, hysterectomy 15 ****  p value based on the χ 2 test < 4 500 g vs. ≥ 4 500 g
All modes of delivery	2 005 (88%)	249 (11%)	23 (1%)	2 277
Mode of delivery (* 1 )					0.000****
Spontaneous	1 229 (61%)	131 (53%)	11 (50%)	1 371 (60%)
Vaginal-surgical	179 (9%)	15 (6%)	0 (0%)	194 (9%)
Prim. section	268 (13%)	52 (21%)	6 (27%)	326 (14%)
Sec. section	329 (16%)	51 (20%)	5 (23%)	385 (17%)
Mode of delivery, vaginal (* 1 )	1 408 (70%)	146 (59%)	11 (50%)	1 565 (69%)	0.000
Bleeding (* 95 )					0.001
< 500 ml	1 157 (60%)	118 (48%)		1 275 (58%)
500 – 999 ml	666 (34%)	108 (44%)		774 (35%)
≥ 1000 ml	112 (6%)	21 (9%)		133 (6%)
Adverse maternal outcome*** (* 166 )	799 (42%)	81 (44%)	15 (71%)	895 (42%)	0.023
Only spontaneous or vaginal-surgical mode of delivery	1 408 (90%)	146 (9%)	11 (1%)	1 565
Birth injury (* 12 )
None	685 (49%)	71 (50%)	5 (46%)	761 (49%)
Grade I/II perineal laceration	450 (32%)	45 (32%)	5 (46%)	500 (32%)
Grade III/IV perineal laceration	31 (2%)	2 (1%)	0	33 (2%)
Cervical laceration	9 (1%)	2 (1%)	0	11 (1%)
Other	226 (16%)	21 (15%)	1 (9%)	248 (16%)
Birth injury, severe (* 12 )	40 (3%)	4 (3%)		44 (3%)	1.000**
Episiotomy (* 9 )	326 (23%)	38 (25%)		364 (23%)	0.692
Blood loss ≥ 500 ml (* 58 )	190 (14%)	26 (19%)	4 (36%)	220 (15%)
		30 (21%)			0.029
Adverse maternal outcome*** (* 58 ) 15	256 (19%)	35 (24%)		291 (19%)	0.121
	286 (19%)		5 (46%)		0.043
Vaginal-surgical delivery	178 (13%)	15 (10%)		193 (12%)	0.264
Only spontaneous, vaginal-surgical or sec. section mode of delivery	1 737 (89%)	197 (10%)	16 (1%)	1 950
Sec. section	329 (19%)	51 (26%)	5 (31%)	385 (20%)
		56 (26%)			0.011
Emergency section	22 (1%)	3 (2%)	0	25 (1%)	0.749****
Drug-based induction (* 15 )	657 (38%)	89 (43%)		746 (39%)	0.165