Neonatal outcomes in pregnancies resulting from oocyte donation: a cohort study in Sweden

BACKGROUND Pregnancies resulting through oocyte donation have been associated with increased risk for adverse outcomes for the mother, such as gestational hypertensive disorders. However, little is known about possible neonatal complications of such pregnancies. The purpose of this study was to evaluate the neonatal health outcomes among singleton pregnancies in a population of relatively young and healthy oocyte recipients in Sweden, taking into account the medical indication leading to treatment. METHODS This cohort study involved 76 women conceiving with donated oocytes, 149 age-matched nulliparous women conceiving spontaneously and 63 women conceiving after non-donor IVF. Participants were recruited during 2005-2008 and followed up until delivery. Data on neonatal outcomes were retrieved from the National Birth Medical Register and the medical records of oocyte recipients from seven Swedish University Hospitals with IVF clinics. Logistic regression analyses were performed to examine the association of mode of conception and neonatal outcomes, adjusted for maternal age and BMI, gestational age and delivery by cesarean section. RESULTS Infants conceived through oocyte donation had higher odds for premature delivery [OR 2.36, 95 % CI (1.02-5.45)], for being small for gestational age [OR 4.23, 95 % CI (1.03-17.42)] and having Apgar score below 7 at 5 min [OR 10.57, 95 % CI (1.21-92.20)] compared to spontaneously conceived infants. Similar trends were observed when comparing infants conceived through oocyte donation to those conceived by traditional IVF. Furthermore, donor oocyte infants had a lower mean birthweight and length compared to autologous oocyte neonates (p = 0.013); however no differences were noted among infants born at term. Neonatal outcomes were more favorable among women with diminished ovarian reserve compared to those with other indications for oocyte donation. CONCLUSIONS Infants conceived after oocyte donation in Sweden have higher odds of being born prematurely and having lower mean birthweight in comparison to non-donor infants. It seems that these unfavorable neonatal outcomes are present despite the age, weight and health restrictions applied to recipients before oocyte donation treatment in Sweden.