Purpose Evaluation of obstetric and neonatal outcomes in a Brazilian retrospective cohort of pregnancies after Roux-en-Y gastric bypass (RYGB), regarding the 2009 Institute of Medicine (IOM) recommendations about gestational weight gain (GWG) and RYGB-conception interval. Additionally, search for intrapopulation risk factors for small gestational age (SGA) offspring and mental health assessments. Material and methods Retrospective analysis of 132 singleton pregnancies after RYGB. Obstetric and neonatal outcomes were analyzed with stratification in above, below, or meeting the target regarding GWG guidance, and 0-12, 12-47, and ≥48 months for RYGB-conception interval. SGA risk factors were identified through Poisson regression analysis. Results GWG below the recommendations was associated with prematurity (p 0.003). Late conceptions (≥48 months) were associated with iron deficiency (p 0.025). Parenteral iron prescription was a protective factor for SGA, with a relative risk of 0.41 (95% CI, 0.20-0.85; p 0.017), and GWG below target was a SGA risk factor, with a relative risk of 4.68 (95% CI, 1.48-14.8; p 0.008). In all, 15.2% of patients had psychopharmacological treatment during pregnancy, and 7.6% received a diagnosis of postpartum depression. Any alcohol and tobacco consumption were reported in 3.8 and 6.8% of patients, respectively. Conclusion The recommendations regarding GWG apply to the RYGB population, and surgery-conception intervals should be individualized. The parenteral iron prescription was a protective factor for SGA, and GWG below the recommendations of the IOM was a risk factor for SGA. Psychological and psychiatric care should be offered to every possible pregnancy after RYGB.

The preoperative stage of bariatric surgery requires that the patient be informed of the obesity-related comorbidities and the risks, benefi ts, and consequences of surgery. The study examined the preoperative risk perception of bariatric surgery in 128 patients with different comorbidities (heart disease, type 2 diabetes mellitus, hypertension, sleep apnea and dyslipidemia). Risk perception of surgery and associated comorbidities were evaluated using a risk perception questionnaire. Patients with diabetes mellitus type 2, systemic hypertension, and sleep apnea were signifi cantly more likely to perceive the risk of surgery compared to those with the other comorbidities. The results showed that educational interventions expand the risk perception of surgery, but independently of the perceived risk of the different comorbidities of obese patients. The study points to the possibility of identifying predictive factors of behavioral intention related to risk perception to improve short and long-term treatment outcomes in patients whose comorbidities are seen as posing no additional health risk.

Study question Does body weight have any effect on clinical and perinatal outcomes in assisted reproduction techniques (ART)? Summary answer Obesity and overweight were associated with smaller oocytes retrieved and mature number, tendency to minor pregnancy rates, and with a greater chance of macrosomic newborns. What is known already The body mass index (BMI) is an international measure to categorize population regarding body weight. Overweight and obesity have an established negative impact on female fertility, especially due to chronic anovulation. However, studies are inconsistent regarding body weight and ART clinical and perinatal outcomes. Some say there is no difference, others show a little or unfavorable outcomes in overweight and obese patients. Study design, size, duration Retrospective cohort study performed at an assisted reproductive clinic. A total of 2296 follicle stimulation cycles were included, from 1686 patients, which resulted in 2278 embryo transfers (ET). Both fresh (1942) and vitrified (354) ET cycles were included in the study. The data refers to a period from 2013- 2020 and were collected from electronic records. Participants/materials, setting, methods Sample was divided into groups, according to BMI (kg/m²): Group 01 (<18.5, n = 30 cycles); Group 02 (18.5–24.9, n = 1630 cycles); Group 03 (25–29.9, n = 459 cycles) and Group 04 (≥30, n = 177 cycles). Data were presented as mean±SD, median (interquartile range), or percentage. ANOVA and Chi-square tests were applied, considering p < 0.05. Multiple logistic regression and generalized estimating equations were performed to consider patients and cycles. Main results and the role of chance The mean maternal age was 35.71±3.5 years old. A statistically significant difference was observed in retrieved oocytes and mature oocytes number (MII) when groups 01 and 02 were put together (G01+G02) and compared to groups 03 and 04: (8.8 [8.5–9.2] vs 7.9 [7.3–8.6] vs. 7.2 [5.9–8.4], p = 0.005) and (6.7 [6.4–7] vs 6 [5.5–6.5] vs. 5.3 [4.3–6.3], p = 0.003), respectively. A significant linear tendency to minor pregnancy rates with higher BMI (p = 0.038), with no significant difference in pregnancy rates was found between the four groups (52.6% vs. 47.9% vs. 46.7% vs. 36.3%, p = 0.124). There was no significant difference in cumulative pregnancy, live birth rate, fertilization and implantation rates between groups. Group 04 showed a higher, but not significant, prevalence of macrosomic newborns (p = 0.110). No statistical differences regarding any other clinical and perinatal outcomes were found (prematurity, intensive care unit admission, congenital malformations, Apgar index, newborn percentile, gestational age and birthweight. Limitations, reasons for caution This is a retrospective study with a limited number of patients. Also there was no information on patients’ weight gain throughout pregnancy, and others clinical pregnancy diseases that could affect perinatal outcomes. Wider implications of the findings: The study presented that the higher the weight, there seems to be a tendency towards worse outcomes of ART, especially regarding retrieved oocytes and mature oocytes number. Also, the study draws attention to the possible relationship between obesity and perinatal outcomes, also seen in spontaneous pregnancies. Trial registration number Not applicable