The effect of mode of conception on obstetrical outcomes differs by body mass index.
This study compared the odds of adverse obstetrical outcomes of pregnancies in women who conceived from IVF (n = 464) versus spontaneous conception (n = 1171) after stratification into three body mass index (BMI) groups: normal weight (18.5-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)) and obese (>30 kg/m(2)). With increasing BMI, incidences of complications between IVF and spontaneously conceived groups narrowed. Among women with normal BMI, IVF pregnancies were associated with increased odds of placental ischaemic disorders (11.3% versus 7.0%, adjusted odds ratio [aOR] = 2.24; 95% confidence interval [CI] = 1.25-4.04) and low birthweight <2500 g (10.6% versus 8.0%, aOR = 2.08; 95% CI = 1.12-3.88). Among overweight women, only low birthweight (<2500 g) was significantly increased (15.6% versus 6.2%, aOR = 4.33; 95%, CI = 1.61-11.63). For obese women, there were no differences between IVF and spontaneously conceived pregnancies for either placental ischaemic disorders (12.5 versus 20.2%, OR = 0.43, 95% CI = 0.17-1.1) or low birthweight (10.0% versus 11.0%, aOR = 0.7, 95% CI = 0.24-2.08). Overall, the odds of adverse obstetrical outcomes were not significantly greater in IVF singleton pregnancies compared with those conceived spontaneously as BMI increased.
Division of Reproductive Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Obstetrics, Gynecology, Sheba Medical Center and Sackler School of Medicine, Tel Aviv University, Israel.
Ronit
R
Machtinger
Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Chloe
C
Zera
Division of Reproductive Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Catherine
C
Racowsky
Division of Reproductive Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Stacey
S
Missmer
Division of Reproductive Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Antonio
A
Gargiulo
Department of Obstetrics, Gynecology, Sheba Medical Center and Sackler School of Medicine, Tel Aviv University, Israel.
Eyal
E
Schiff
Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA. Electronic address: lwilkinshaug@partners.org.
Louise
L
Wilkins-Haug
D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D005260:Female; D005306:Fertilization; D005307:Fertilization in Vitro; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008297:Male; D009765:Obesity / Q000150:complications* / Q000473:pathology; D050177:Overweight / Q000150:complications* / Q000473:pathology; D010922:Placenta Diseases / Q000209:etiology / Q000473:pathology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000209:etiology* / Q000473:pathology; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D055815:Young Adult
BMI; IVF pregnancy; obesity; spontaneous pregnancy