The efficacy of Quintero staging system to assess severity of twin-twin transfusion syndrome treated with laser therapy: a systematic review with meta-analysis.

Severity of twin-twin transfusion syndrome (TTTS) is classified in five stages according to Quintero staging. However, the efficacy of such staging was recently debated. We reviewed the efficacy of Quintero staging to predict survival rate in TTTS treated with laser therapy. Articles reporting survival rate for each stage in TTTS treated with laser therapy were reviewed. Number of twins alive per pregnancy (NAP) was compared between early (I + II) and advanced (III + IV) stages and within stages. Meta-analysis was performed according to Meta-analysis Of Observational Studies in Epidemiology guidelines. Heterogeneity was tested with chi-square for heterogeneity at a significance level of P < 0.10, and random or fixed models were generated as appropriate. A P value < 0.05 was considered statistically significant. NAP was similar between early (zero survivors: 34/228, 15%; one survivor: 49/228, 21%; two survivors: 145/228, 63%) and advanced stages (zero survivors: 38/214, 18%; one survivor: 64/214, 30%; two survivors: 112/214, 52%; P > 0.05) except for one survivor ( P < 0.05). A trend for increased NAP was observed in all stages. Because clinically relevant differences were not observed, laser therapy is the optimal treatment for all stages. As Quintero staging does not provide information about prognosis, a new staging system is proposed.