Association between cocaine abuse in pregnancy and placenta-associated syndromes using propensity score matching approach.

AIMS: We used propensity scores matching techniques to assess the association between maternal cocaine abuse in pregnancy and the occurrence of placenta-associated syndromes (PAS). STUDY DESIGN: Mothers who abused cocaine (n=5026) were matched to controls (n=5026) from a sample of 1,693,197, unexposed mothers in Florida from 1998 to 2007. Cocaine abuse was identified using the ICD-9 principal and secondary diagnosis codes (304.2 for cocaine dependence and 305.6 for cocaine abuse). The outcome of interest, PAS, was identified as any indication in diagnosis field of ICD-9-CM codes for: placental abruption (641.2), oligohydramnios (658.0), placental infarction (656.7, 656.8, 656.9), gestational hypertension (642.3, 642.9), preeclampsia (642.4, 642.5, and 642.7) or eclampsia (642.6). RESULTS: Nearly 6% of mothers in the study sample experienced a condition associated with PAS prior to matching. Women who abused cocaine were 58% more likely to have PAS when compared to women who did not (OR=1.48, 95% confidence interval: 1.33, 1.66). Women who abused cocaine were at elevated odds for placental abruption, placenta infarction and preeclampsia with the most pronounced odds noted for placental abruption (OR=2.79, 95% confidence interval: 2.19, 3.55). CONCLUSIONS: These findings indicate that cocaine abuse during pregnancy is associated with more placenta-related disorders than previously reported.

Previous cesarean section, gestational age at first delivery and subsequent risk of pre-eclampsia in obese mothers.

PURPOSE: We examine the association between prior C-section and subsequent pre-eclampsia; and describe the effect of gestational age at prior C-section, and obesity status on this association. METHODS: The study population included women with two subsequent singleton births in Missouri between 1998 and 2005. The risk for pre-eclampsia/eclampsia was assessed among women with and without prior cesarean delivery. The two groups were followed to their second pregnancy and the occurrence of pre-eclampsia was documented. Additionally, the history of pre-eclampsia, prior cesarean at preterm, and obesity status were examined for their differential effects on the risk of pre-eclamsia. RESULTS: Women with prior C-section were 28% more likely to have pre-eclampsia in their subsequent pregnancy [OR = 1.28; 95% CI = 1.20-1.37]. However, this result was not significant when women with pre-eclampsia in their first pregnancy were excluded. After this exclusion, a more than threefold increased risk for subsequent pre-eclampsia was observed in women with prior early C-section [OR = 3.15; 95% CI= 2.43-4.08], while the level of risk did not change in the prior late C-section group [OR = 0.90; 95% CI= 0.82-1.00]. Subgroup analysis suggested that obesity status modified the risk of prior early C-section but did not affect the risk for prior late C-section. CONCLUSION: Preterm C-section in the first pregnancy may be associated with subsequent pre-eclampsia regardless of prior pre-eclampsia status.