Comparison of obstetric outcomes in twin pregnancies after in vitro fertilization, ovarian stimulation and spontaneous conception.

OBJECTIVE

To compare the outcomes of liveborn twin gestations conceived after in vitro fertilization (IVF) or ovarian stimulation with spontaneously conceived twin pregnancies.

METHODS

A review of all twin gestations delivered at Winthrop-University Hospital from 1 January 1999 to 31 December 2000. Women who underwent fetal reduction or had a demise of one twin were excluded. Maternal demographics, antepartum complications, mode of delivery and perinatal outcome were compared.

RESULTS

Sixty pregnancies were conceived after IVF, 34 were conceived by ovarian stimulation and 101 were spontaneously conceived. Women in the IVF group were older (p < 0.001), were more often 35 years or older (p < 0.001) and primiparous (p = 0.005). More women in the ovarian stimulation group had a poor obstetric history (p = 0.04). Spontaneous gestations had a higher incidence of monochorionic placentations (p = 0.002). There were no differences in gestational age at delivery, antepartum complications, or mode of delivery. There were fewer low-birth-weight neonates in the IVF group (odds ratio 0.59, 95% confidence interval 0.35-0.98; p = 0.03) than in the spontaneous group, but the difference disappeared when only the dichorionic pregnancies were compared. Other neonatal outcomes studied were the same among groups.

CONCLUSION

Twin gestations conceived following IVF and ovarian stimulation appear to have similar outcomes to spontaneously conceived twin gestations.