Perinatal Outcomes After Bariatric Surgery Compared With a Matched Control Group.

OBJECTIVE: To evaluate perinatal outcomes associated with pregnancy after bariatric surgery within a large integrated health care system using propensity score matching. METHODS: We conducted a retrospective cohort study that evaluated perinatal outcomes in pregnant patients after bariatric surgery from January 2012 through December 2018. History of bariatric surgery was identified by using International Classification of Diseases codes and a clinical database. Primary outcomes were preterm birth (PTB), gestational hypertension, preeclampsia, impaired glucose tolerance or gestational diabetes, a large-for-gestational-age (LGA) or small-for-gestational-age (SGA) neonates, and cesarean birth. Propensity scores were estimated by using logistic regression that accounted for age at delivery, prepregnancy body mass index, year of delivery, parity, neighborhood deprivation index, race and ethnicity, insurance status, initiation of prenatal visit in the first trimester, smoking during pregnancy, chronic hypertension, and preexisting diabetes. Five patients in the control group were matched to each patient in the case group on linear propensity score, and modified Poisson regression was used to adjust for covariates. Sensitivity analyses by timing and type of surgery were performed. RESULTS: We identified a case cohort of 1,591 pregnancies in patients after bariatric surgery and a matched cohort of 7,955 pregnancies in patients who had not undergone bariatric surgery. Demographic characteristics were similar in both groups. In multivariate models, pregnancy after bariatric surgery was associated with a decreased risk of preeclampsia (7.5% vs 10.2%, adjusted relative risk [aRR] 0.72, 95% CI 0.60-0.86), gestational diabetes or impaired fasting glucose (23.5% vs 35.0%, aRR 0.73, 95% CI 0.66-0.80), and LGA (10.6% vs 19.9%, aRR 0.56, 95% CI 0.48-0.65) and an increased risk of SGA (10.9% vs 6.6%, aRR 1.51, 95% CI 1.28-1.78). No significant differences were observed in PTB, gestational hypertension and cesarean delivery. CONCLUSION: Pregnancy after bariatric surgery in a racially and ethnically diverse cohort of patients is associated with decreased risk of preeclampsia, gestational diabetes or impaired fasting glucose, and LGA neonates; it is also associated with an increased risk of SGA neonates compared with pregnant patients in a matched control group.

Fetomaternal hemorrhage: evaluation of recurrence within a large integrated healthcare system.

BACKGROUND: Fetomaternal hemorrhage is associated with severe fetal morbidity and mortality. The recurrence risk of fetomaternal hemorrhage is unknown. OBJECTIVE: We sought to establish the recurrence rate of fetomaternal hemorrhage in a large integrated healthcare system over a 10-year period. STUDY DESIGN: In this retrospective study within the Kaiser Permanente Northern California medical system, cases of fetomaternal hemorrhage were defined by either an elevated fetal hemoglobin level as determined by flow cytometry for a concerning pregnancy outcome (preterm delivery, perinatal demise, neonatal anemia, or transfusion within the first 2 days of life) or by perinatal demise with autopsy findings suggestive of fetomaternal hemorrhage. The outcomes of subsequent pregnancies were reviewed for features of recurrence. RESULTS: Within the 2008 to 2018 birth cohort of 375,864 pregnancies, flow cytometry testing for fetal hemoglobin levels was performed in 20,582 pregnancies. We identified 340 cases of fetomaternal hemorrhage (approximately 1 in 1100 births). Within the cohort of 340 affected pregnancies, perinatal loss was recorded for 80 (23.5%) pregnancies and 50 (14.7%) pregnancies delivered neonates who required transfusion. The affected patients had 225 subsequent pregnancies of which 210 were included in the analysis. Of these, 174 (82.9%) advanced beyond the threshold of viability and were delivered within our healthcare system. There was 1 case of recurrent fetomaternal hemorrhage identified. The recurrent case involved a spontaneous preterm delivery of an infant who was noted to have an elevated reticulocyte count but was clinically well. CONCLUSION: Within our large integrated healthcare system, approximately 1 in 1100 pregnancies was affected by fetomaternal hemorrhage within a 10-year period, which is comparable with previous studies. We identified 1 case of recurrence, yielding a recurrence rate of 0.5%. This infant did not have features of clinically important fetomaternal hemorrhage. This information can inform counseling of patients with affected pregnancies.