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.