Table 4.

Correlates of length of treatment and total dose of morphine

n = 68	Length of treatment			Total dose of morphine
Predictor	b	Wald χ2	P	b	Wald χ2	P
Birth weight	0.0003	1.92	0.17	0.0007	2.11	0.15
EGA at delivery	0.06	0.92	0.34	0.16	1.60	0.21
Delivery type	−0.29	−1.40	0.24	−0.83	3.26	0.07
Maternal maintenance dose	0.003	1.52	0.22	0.003	0.20	0.65
Maternal weight	−0.002	0.49	0.48	−0.006	0.95	0.33
Days of study medication	−0.004	2.93	0.09	−0.01	6.95	0.008*
Anxiolytics	0.006	0.00	0.97	−0.09	−0.04	0.89
SSRIs	0.19	0.90	0.34	0.89	5.77	0.02+
Cigarettes	0.02	3.18	0.07	0.05	3.86	0.05+

⁺P < 0.05.

^*P < 0.01.

^**P < 0.001.

Note: SSRIs: selective serotonin reuptake inhibitor; days of study medication: maternal maintenance medication