MATERNAL AND PERINATAL OUTCOMES IN PREGNANCIES DERIVING FROM ASSISTED REPRODUCTIVE TECHNOLOGIES (ART)

INTRODUCTION Pregnancies deriving from assisted reproductive technology (ART) have more obstetrical and perinatal complications than spontaneous pregnancies. The reason for this discrepancy is not clear, but it could be related to the higher rate of multiple gestations, older maternal age, the use of fertility medications, or probably a combination of these factors. Previous studies have reported the incidence of these complications in different separate categories: complicated or uncomplicated term pregnancy, single or twins, or they have reported the influence of a single parameter: age, BMI, etc. In order to give preconception counseling to couples that want to undergo ART, it is important to have data about the global incidence of adverse outcomes related to ART when compared to a population who did not receive ART and that was followed and delivered at the same hospital. The aim of this study was to evaluate the global obstetrical outcome of pregnancies obtained from ART, using the data from spontaneous pregnancies followed and delivered at the same hospital during the same period of time as matched controls. METHODS We retrospectively analyzed the clinical records of all the singleton pregnancies of patients admitted for delivery at a regional tertiary medical center between January and December 2014. We divided our study population into two groups: one related to pregnancies obtained by ART (ART group) and one related to pregnancies after spontaneous conception (control group). Maternal characteristics such as age, BMI, diabetes, hypertension and exposition to smoke were reported. Pregnancy and delivery outcomes such as gestational hypertension, gestational diabetes, gestational thyreopathy, cholestasis, postpartum haemorrhage, induction of labour, recurrence to episiotomy or Kristeller manoeuvre, mode and gestational age at delivery, premature rupture of membranes, IUGR, fetal malformations, birthweight and placenta location were also reported for each group. Statistical analysis. The Chi square test was used to analyze statistically significant relations between the distribution of categorical variables. Student’s t test was used to compare significant differences in mean continuous variables between the two groups. A p value < 0.05 was considered statistically significant. RESULTS A total of 159 pregnancies obtained by ART and 3,144 spontaneous pregnancies were included in the study. Mothers who received ART had a higher risk of developing obstetrical complications such as placenta previa (p < 0.005) and postpartum hemorrhage (p = 0.05) compared to mothers with spontaneous pregnancies. In the ART group a higher rate of invasive maneuvers such as episiotomy (p = 0.02), Kristeller (p < 0.005) and caesarean section (p < 0.005) were reported. Pregnancies after ART had significantly increased risk of preterm birth (p = 0.05) and low birthweight (p = 0.007) compared to spontaneous pregnancies. CONCLUSION This study shows that ART itself represents a risk factor in the development of an adverse obstetrical outcome including placenta previa and postpartum hemorrhage. Our study population was homogeneous, as the two groups of cases and controls were comparable in terms of age, BMI and pre-gestational risk factors such as chronic hypertension, diabetes and exposition to smoke. ART seems to be related to an augmented rate of invasive maneuvers such as episiotomy, Kristeller and caesarean section and it is independent of maternal age, in contrast to what had been reported in previous studies. Finally, the newborns of women submitted to ART are often premature and with a low birth weight compared to newborns of women with a spontaneous conception.