Peripartum and postpartum outcomes in uncomplicated term pregnancy following ART: a retrospective cohort study from two Italian obstetric units.

STUDY QUESTION: Do singleton uncomplicated term pregnancies conceived by assisted reproductive technology (ART) have adverse peripartum and postpartum outcomes? SUMMARY ANSWER: Term pregnancies following ART, even if uncomplicated until birth, have a higher risk of retained placenta and postpartum hemorrhage (PPH). WHAT IS KNOWN ALREADY: There is consistent evidence that pregnancies following ART have higher incidence of complications during pregnancy. However, few studies specifically investigated birth outcomes in ART term pregnancies. STUDY DESIGN SIZE DURATION: A retrospective cohort study was conducted on 14 415 deliveries at two university tertiary care obstetric units. Clinical data were extracted by reviewing obstetric records of all deliveries from 1 January 2010 to 31 December 2014, in a standardized electronic database regarding the mother's health before and during pregnancy, complications during pregnancy and at birth, and neonatal outcome. PARTICIPANTS/MATERIALS SETTING METHODS: Following an accurate evaluation of exclusion criteria (multiparity, maternal pre-pregnancy diseases, prior uterine surgery, fetal malformations, intrauterine deaths, elective cesarean section and pregnancy complications), the group of uncomplicated singleton term pregnancies from autologous ART conception by in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (n = 188) was compared with a maternal age and body mass index (BMI) matched group of spontaneous pregnancies (n = 1168). Cases of intrauterine insemination (IUI) (n = 14) and ovulation induction with timed intercourse (n = 18) were not included. Labor, delivery and postpartum outcomes were evaluated. Odds ratios (OR) were adjusted with multivariable logistic regression to maternal age, BMI, nationality and gestational age at birth. MAIN RESULTS AND THE ROLE OF CHANCE: The age of women in the final analysis ranged from 25 to 45 years, while BMI ranged from 17 to 34 kg/m2. Uncomplicated term pregnancies with ART conception had a higher risk of operative delivery (adjusted OR 1.40, 95% confidence interval (CI) 1.01-1.95), retained placenta (adjusted OR 2.63, 95% CI 1.31-5.26) and PPH (adjusted OR 2.86 95% CI 1.37-5.99). Conversely, ART conception did not increase the risk of induced labor (adjusted OR 1.18, 95% CI 0.85-1.65). However, patients that conceived by ART and underwent labor induction had a higher risk of failed induction compared with the control group (adjusted OR 2.53, 95% CI 1.23-5.21). Infants born after ART had a similar birthweight, Apgar score and arterial blood pH compared with spontaneously-conceived ones. LIMITATIONS REASONS FOR CAUTION: The database lacked specific information about causes of infertility, smoking habit, family income and details on ART (fresh versus frozen cycle, IVF versus ICSI), limiting, in part, our analysis of the results. However, only autologous IVF/ICSI pregnancies were included in order to prevent bias related to conception by oocyte/embryo donation. In vivo conception ART cases were excluded because they were too few to allow comparison with IVF/ICSI. Nevertheless, the inclusion of only uncomplicated pregnancies provides a highly homogeneous and still representative population sample. Study sample is representative of a well-resourced obstetric facility in a high-income country, limiting to some extent the generalizability of study results. WIDER IMPLICATIONS OF THE FINDINGS: Pregnancies conceived by autologous ART that proceed uncomplicated until term may require counseling about the risk of placental retention with PPH. STUDY FUNDING/COMPETING INTERESTS: The authors have no conflict of interest and funding to declare.

Twin pregnancies after assisted reproductive technologies: the role of maternal age on pregnancy outcome.

OBJECTIVES: Our aim was to investigate whether advanced maternal age (≥40years) still impairs the outcome of twin pregnancies after assisted reproductive techniques (ART). STUDY DESIGN: The retrospective observational study evaluated 430 nulliparous dichorionic diamniotic twin pregnancies conceived with ART. The population was divided into women <40 years old (Group A, n=265) and ≥40 years old (Group B, n=165). RESULTS: Gestational diabetes mellitus and gestational hypertension/preeclampsia were significantly more frequent in nulliparous twin pregnancies after ART ≥40years compared to <40years (p=0.021 and p<0.001, respectively). In univariate analysis of twin pregnancies after ART, there was only a trend of higher incidence of total preterm birth (PB) rate within mother aged ≥40 years old (p=0.104). However, Group A showed higher rate of spontaneous preterm birth (SPB) <37 weeks, whereas Group B showed significantly higher rate of iatrogenic PB <37 weeks of gestation (p=0.023 and p=0.001, respectively). For delivery <32 weeks of gestation, the rate of SPB in Group A was significantly higher (p=0.002). A higher incidence of PB was observed in Group B after heterologous treatment (p<0.001). Despite this, the absolute prevalence of PB in the entire population is higher in Group A, both after autologous (22.5%) and heterologous (25%) ART treatment, than in Group B (10.1% vs 21.4%). CONCLUSIONS: Our data indicate that nulliparous twin pregnancies conceived with ART in mothers ≥40 years old did not show significantly higher incidence of PB, even if an increased rate of iatrogenic PB <37 weeks is showed.

Ultrasound estimated fetal weight slightly below the median is associated with increased risk of spontaneous preterm birth.

BACKGROUND: This study investigates the possible relationship between ultrasound estimated fetal weight (EFW) at third trimester and the risk of preterm birth following spontaneous preterm labor in otherwise uncomplicated pregnancies. METHODS: We performed a nested case-control study including 281 cases of spontaneous preterm labor with preterm delivery in the third trimester and 3372 matched controls within a cohort of 6207 consecutive pregnant women. Pregnancies with fetal growth restriction (birth weight <10th centile of population-based normograms) or fetal anomalies were not included. EFW was calculated by using Hadlock's formula and converted to fetal gender adjusted multiples of median (MoM) for each gestational age. RESULTS: EFW correlated with birth weight (r = 0.959, p < 0.0001) and was lower in preterm than in control fetuses (p < 0.0001). The odds ratios (95% confidence intervals) for preterm birth for fetuses below 0.9 MoM, 0.85 MoM, 0.80 MoM, and 0.75 MoM of EFW were, respectively, 4.6 (3.6-5.9), 5.7 (4.3-7.5), 8.5 (5.9-12.1), and 11.2 (6.8-18.3). The independent relationship between preterm birth and lower EFW was confirmed in multivariate analysis with adjustment for potential confounders, such as maternal age, parity, and fetal gender. CONCLUSION: In asymptomatic women between 28 and 36 weeks of gestation, an EFW lower than 0.90 MoM increases by 4.6 times the risk of spontaneous preterm birth, and the risk increases proportionally to the degree of weight reduction.