Prior studies show conflicting evidence as to whether obesity in the absence of other medical or pregnancy-related conditions contributes to amniotic fluid disorders. The purpose of this study is to determine the association between late-pregnancy obesity with oligohydramnios (amniotic fluid index [AFI]<5 or maximum vertical pocket [MVP]<2) and/or polyhydramnios (AFI>24 or MVP>8).
This is a retrospective cohort study of 966 women with singleton gestations who had one or more obstetrical ultrasounds at Mount Sinai South Nassau at 36 0/7 weeks of gestation or beyond between August 1, 2015, and May 1, 2020. Patients were included if they had valid pregnancy dating and a documented AFI and/or MVP. Patients were categorized based on body mass index (BMI) (eg, normal, overweight, class I obesity, class II obesity, or class III obesity). Chi-square analyses were performed to evaluate whether there was a relationship between BMI and AFI. A logistic regression analysis was then performed for any confounding variables.
There was no significant association between oligohydramnios and increasing BMI, whether patients had overweight (P=.17), class I (P=.46), class II (P=.49), or class III obesity (P=.99). The same was true for polyhydramnios and increasing BMI, whether patients had overweight (P=.68), class I (P=.74), class II (P=.94), or class III obesity (P=.99).
Elevated maternal BMI was not significantly associated with disorders of amniotic fluid, regardless of the severity of obesity.