Obesity and the risk of spontaneous abortion after oocyte donation.
OBJECTIVE
To determine whether obesity increases the risk of spontaneous abortion.


METHODS
Retrospective study.


METHODS
Oocyte donation program at the Instituto Valenciano de Infertilidad in Spain.


METHODS
Seven hundred twelve cycles of recipients of ovum donation with known body mass index (BMI), good-quality embryo transfer, and absence of uterine pathology or clinical history of antiphospholipid antibodies or recurrent abortion.


METHODS
Recipients were divided in four BMI (kg/m(2)) groups: lean, with BMI <20 (n = 92; 12.9%); normal, with BMI = 20-24.9 (n = 398; 55.9%); overweight, with BMI = 25-29.9 (n = 172; 24.2%); and obese, with BMI >/=30 (n = 50; 7%). Clinical parameters were compared among the groups.


METHODS
Spontaneous abortion rates according to BMI.


RESULTS
No difference was found among the four BMI groups in any of the parameters of the cycle analyzed. The overall abortion rate was 15.8% (57 of 360). There were significant differences in abortion rates between the obese (38.1%), and the normal (13.3%) and overweight (15.5%) groups. When several cutoff BMI values were established (20, 25, and 30), only the obese women demonstrated a greater risk of abortion. Compared with the normal population, the obese group showed a significant fourfold increase in the risk of spontaneous abortion.


CONCLUSIONS
Our findings confirm that obesity (BMI >/=30) is an independent risk factor for spontaneous abortion. Therefore, it would be advisable for obese patients to reduce weight before becoming pregnant.
Instituto Valenciano de Infertilidad (IVI), Valencia, Spain.
José
J
Bellver
Luis P
LP
Rossal
Ernesto
E
Bosch
Andrés
A
Zúñiga
José T
JT
Corona
Fernando
F
Meléndez
Emilio
E
Gómez
Carlos
C
Simón
José
J
Remohí
Antonio
A
Pellicer
D000022:Abortion, Spontaneous / Q000209:etiology*; D000328:Adult; D015992:Body Mass Index; D005260:Female; D006801:Humans; D009765:Obesity / Q000150:complications*; D018587:Oocyte Donation / Q000009:adverse effects*; D011085:Polycystic Ovary Syndrome / Q000150:complications; D012189:Retrospective Studies; D012307:Risk Factors