Table 4.

Pregnancy loss incidence by urine-measured^a opioid use among women in the EAGeR cohort who became pregnant

Opioid use exposure	N, exposed and unexposedb	N (%), losses	Unadjusted RR (95% CI)c	Adjusted RR (95% CI)d
Overall	785	188 (24)
At baseline
Negative	731	174 (24)	Reference	Reference
Positive	42	10 (24)	0.88 (0.55, 1.4)	0.96 (0.55, 1.7)
Any time before conception
Negative	721	170 (24)	Reference	Reference
Positive	57	15 (26)	1.11 (0.76, 1.6)	1.16 (0.72, 1.9)
Last preconception cycle
Negative	719	169 (24)	Reference	Reference
Positive	33	11 (33)	1.29 (0.84, 2.0)	1.5 (0.85, 2.6)
Week 4 of pregnancyg
Negative	720	152 (21)	Reference	Reference
Positive	20	8 (40)	2.2 (1.3, 3.5)	2.09 (1.1, 4.1)
During first 8 weeks of pregnancyg
Negative	653	82 (13)	Reference	Reference
Positive	33	9 (27)	2.4 (1.4, 4.0)	2.5 (1.3, 5.0)

RR, risk ratio; CI, confidence interval.

^aIncludes oxycodone, hydrocodone, noroxycodone, oxymorphone, codeine, dihydrocodeine, hydromorphone, morphine, desomorphine, heroin, levorphanol, thebaine, tramadol, and fentanyl.

^bRestricted to women who became pregnant. Numbers include participants with measured data. Multiple imputation was used to account for missing exposure and covariate information, thus all 785 participants with complete follow-up were included in analyses of RR.

^cFrom Poisson regression models restricted to women who became pregnant. Inverse probability weights were used to account for possible selection bias resulting from this restriction.

^dAdjusted for age, race, body mass index, education level, physical activity, smoking frequency, alcohol use frequency, urine-measured marijuana use and antidepressant use at baseline, past opioid use prior to or during a woman’s last pregnancy, gynecological indication for opioid use, severity of abdominal cramping and lower backache during menstrual periods, time since a woman’s last pregnancy, and number of prior pregnancy losses.

^eRestricted to women who had a pregnancy lasting at least 4 weeks. Inverse probability weights were used to account for possible selection bias resulting from this restriction. Multivariable model is adjusted for preconception opioid use and abdominal pain and cramping in the two weeks prior to opioid measurement.

^fRestricted to women who had a pregnancy lasting at least 8 weeks. Inverse probability weights were used to account for possible selection bias resulting from this restriction. Multivariable model is adjusted for preconception opioid use and abdominal pain and cramping in the two weeks prior to opioid measurement.