An Analysis of the NSW Midwives Data Collection over an 11-Year Period to Determine the Risks to the Mother and the Neonate of Induced Delivery for Non-Obstetric Indication at Term

Table 1

Outcomes of induction with non-obstetric indication by different gestational age groups.

Outcomes	Gestational Age group						𝑃-value^†
	37 weeks	38 weeks	39 weeks	40 weeks	≥41 weeks	Total
Maternal mean age (years)	30.1	30.9	31.1	30.7	29.5	30.2	<0.001
Primigravida	984/3192 (30.8%)	3502/13930 (25.1%)	6046/21391 (28.3%)	16054/39973 (40.2%)	39705/73133 (54.3%)	66291/151619 (43.7%)	<0.001
Maternal Smoking	529/3179 (16.6%)	1885/13915 (13.5%)	2530/21369 (11.8%)	4761/39931 (11.9%)	10690/73021 (14.6%)	20395/151415 (13.5%)	<0.001
Normal Vaginal	2524/3194 (79.0%)	10820/13934 (77.7%)	16191/21391 (8.2%)	27766/39965 (69.5%)	46741/73132 (63.9%)	104042/151616 (68.6%)	<0.001
Forceps	94/3194 (2.9%)	470/13934 (3.4%)	1043/21391 (4.9%)	2523/39965 (6.3%)	4189/73132 (5.7%)	8319/151616 (5.5%)	<0.001
Vacuum Extraction	190/3194 (5.9%)	1145/13934 (8.2%)	1736/21391 (8.1%)	3804/39965 (9.5%)	7114/73132 (9.7%)	13989/151616 (9.2%)	<0.001
Caesarean Section	377/3195 (11.8%)	1454/13942 (10.4%)	2362/21398 (11%)	5799/39984 (14.5%)	15009/73164 (20.5%)	25001/151683 (16.5%)	<0.001
Intact Perineum	1002/2301 (43.5%)	3997/10030 (39.9%)	5730/15510 (36.9%)	11066/31163 (35.5%)	21176/56479 (37.5%)	42971/115483 (37.2%)	<0.001
Admitted to NICU	81/2301 (3.5%)	153/10030 (1.5%)	175/15509 (1.1%)	236/31161 (0.8%)	613/56477 (1.1%)	1258/115478 (1.1%)	<0.001
Postpartum Haemorrhage	11/893 (1.2%)	60/3910 (1.5%)	115/5883 (2.0%)	167/8814 (1.9%)	347/16675 (2.1%)	700/36175 (1.9%)	>0.05
Surgical Repair of Vagina or Perineum	1373/3194 (43.0%)	6964/13937 (50.0%)	11594/21394 (54.2%)	22309/39978 (55.8%)	37792/73150 (51.7%)	80032/151653 (52.8%)	<0.001
Apgar < 5 at 1 Minute	127/3191 (4.0%)	396/13935 (2.8%)	572/21392 (2.7%)	1227/39971 (3.1%)	3228/73143 (4.4%)	5550/151632 (3.7%)	<0.001
Apgar < 7 at 5 Minutes	79/3191 (2.5%)	180/3191 (1.3%)	230/21391 (1.1%)	474/39967 (1.2%)	1176/73144 (1.6%)	2139/151630 (1.4%)	<0.001
Still birth	5/2300 (0.22%)	10/10028 (0.09%)	9/15506 (0.06%)	14/31162 (0.04%)	30/56470 (0.05%)	68//115347 (0.06%)	<0.001
Neonatal Death	3/2296 (0.13%)	8/10020 (0.08%)	3/15501 (0.02%)	9/31149 (0.03%)	28/56449 (0.05%)	51/115415 (0.04%)	<0.001
Perinatal Death	8/2300 (0.35%)	18/10028 (0.18%)	12/15506 (0.08%)	23/31162 (0.07%)	58/56470 (0.10%)	119/115347 (0.10%)	<0.001
Birth Weight (grams)	3153	3386	3526	3646	3724	3632	<0.001
Birth Weight < 2,500 grams	174/3192 (5.5%)	215/13937 (1.5%)	121/73144 (0.6%)	99/39973 (0.2%)	121/73144 (0.2%)	730/151630 (0.5%)	<0.001
Mean Length of Stay of Baby (days)	3.9	3.7	3.6	3.7	3.5	3.6	<0.001

^†𝑃-value for overall difference.