Table 5.

 Incremental cost effectiveness ratios and net benefit statistics for maternal morbidity avoided in women at low risk of complications according to planned place of birth: home, freestanding midwifery unit (FMU), or alongside midwifery unit (AMU) with obstetric unit (OU) as reference

	Home	FMU	AMU
All low risk women
Cost difference (95% CI)	−590 (−618 to −563)	−247 (−280 to −211)	−154 (−190 to −118)
Difference in maternal morbidity* avoided (95% CI)	0.195 (0.187 to 0.204)	0.172 (0.168 to 0.182)	0.116 (0.106 to 0.126)
Mean ICER (95% CI)	−3024 (−3138 to −2912)	−1442 (−1600 to −1284)	−1322 (−1572 to −1049)
Quadrant on cost effectiveness plane	South east	South east	South east
Mean net benefit (95% CI)†	4498 (4306 to 4669)	3683 (3451 to 3904)	2486 (2259 to 2692)
Mean net benefit (95% CI)§	6451 (6175 to 6705)	5403 (5068 to 5716)	3651 (3322 to 3950)
Low risk women without complicating conditions
Cost difference (95% CI)	−504 (−535 to −474)	−150 (−186 to −115)	−69 (−105 to −36)
Difference in maternal morbidity* avoided (95% CI)	0.165 (0.156 to 0.174)	0.139 (0.131 to 0.149)	0.088 (0.078 to 0.098)
Mean ICER (95% CI)	−3052 (−3215 to −2902)	−1075 (−1285 to −843)	−782 (−1130 to −431)
Quadrant on cost effectiveness plane	South east	South east	South east
Mean net benefit (95% CI)†	3808 (3620 to 4012)	2942 (2743 to 3166)	1828 (1605 to 2059)
Mean net benefit (95% CI)§	5459 (5181 to 5754)	4340 (4051 to 4658)	2706 (2382 to 3040)

*Defined as at least one of: general anaesthetic; instrumental birth; caesarean section; third or fourth degree perineal trauma; blood transfusion; admission to intensive treatment unit, high dependency unit, or specialist unit; and maternal death (within 42 days of giving birth). This is composite measure and was also secondary outcome of interest in cohort study.

†Estimated at £20 000 cost effectiveness threshold.

§Estimated at £30 000 cost effectiveness threshold.