Risk for congenital malformations in offspring of women who have undergone bariatric surgery. A national cohort.
OBJECTIVE
To study the risk for congenital anomalies in the first child of women after bariatric surgery compared with all other women giving birth to their first child and divided by maternal body mass index (BMI) groups.


METHODS
Prospective, population-based register study.


METHODS
Sweden.


METHODS
All firstborn children to women born 1973-83 were studied to determine if they had a congenital anomaly and a mother who had undergone bariatric surgery before pregnancy.


METHODS
A total of 270,805 firstborns; of which 341 had mothers who had had bariatric surgery before delivery. We retrieved information on the women's marital or cohabitation status, smoking, BMI, diabetes and hypertension during pregnancy.


METHODS
Congenital malformations.


RESULTS
Of the firstborn children to mothers who had had bariatric surgery before pregnancy, 4.1% (95% confidence interval [95% CI] 2.2-6.0) were malformed compared with 3.4% (95% CI 3.3-3.5) of those whose mothers had not undergone bariatric surgery. The risk for congenital malformation in firstborn children increased with increasing maternal BMI. The adjusted odds ratio (OR) for congenital malformation among children whose mothers' BMI ranged between 25 and 29 kg/m(2) was 1.09 (95% CI 1.03-1.15), whose mothers' BMI ranged between 30 and 34 kg/m(2) was 1.14 (1.05-1.24) and whose mothers' BMI was ≥35 kg/m(2) was 1.30 (95% CI 1.16-1.45) compared with those whose mothers had a normal BMI. Bariatric surgery before pregnancy did not have any effect on the odds ratio for having congenital malformation (OR = 1.09, 95% CI 0.63-1.91).


CONCLUSIONS
Preconception bariatric surgery does not seem to affect the risk for congenital malformations but a high to very high BMI does appear to increase the risk.
Division of Obstetrics and Gynecology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden; Department of Obstetrics and Gynaecology in Linköping, County Council of Östergötland, Linköping, Sweden.
A
A
Josefsson
M
M
Bladh
A-B
AB
Wiréhn
G
G
Sydsjö
D000293:Adolescent; D000328:Adult; D050110:Bariatric Surgery / Q000009:adverse effects*; D001722:Birth Order; D015992:Body Mass Index; D000013:Congenital Abnormalities / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000601:surgery; D016742:Preconception Care / Q000706:statistics & numerical data; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult
Bariatric surgery; birth defects; congenital malformations; obesity; pregnancy