Amniotic Fluid and Maternal Blood Characteristics in Severe Mid-Trimester Twin–Twin Transfusion Syndrome

Abstract

Objective: To investigate the concentrations of metabolic variables in the amniotic fluid of the recipient twin and maternal blood and to correlate them with clinical features, which are characteristic for the course of pregnancies with twin–twin transfusion syndrome (TTS). Materials and Methods: In 109 pregnancies with severe mid-trimester TTS, we measured the concentrations of interleukin-6 (IL-6), α-fetoprotein (AFP), sodium, potassium, total protein, β₂-microglobulin and osmolality in the amniotic fluid of the recipient twin prior to laser coagulation of the vascular anastomoses and compared them to a control group of 92 singleton pregnancies. We measured the pulsatility index (PI) of ductus venosus flow velocity waveforms in the recipient twin and performed a retrospective chart analysis for complete maternal blood count before and after the procedure. Results: All variables, except osmolality, IL-6 and AFP were significantly lower in the TTS group. There was a significant positive correlation between PI in the ductus venosus and the amniotic fluid AFP concentrations (r = 0.355; p < 0.001). There was a significant fall in complete maternal blood count after laser therapy (p < 0.001) and a significant correlation between the amount of amniotic fluid drained and the fall of maternal Hb (r = –0.261; p = 0.03) and hematocrit (r = –0.212; p = 0.01). Conclusion: Pathophysiologic changes in TTS do not only occur at the inter-twin level of placental vascular anastomoses but also at the materno-fetal level of fluid exchanges. AFP is correlated to the severity of congestive heart failure of the recipient twin.

Maternal Plasma and Amniotic Fluid Cytokines in Monochorionic, Diamniotic Twin Pregnancies Complicated by Twin-to-Twin Transfusion Syndrome

“…TH1/TH2 cytokines were not significantly different in maternal plasma between the cases of uncomplicated MC and DC twins and those affected by severe TTTS. This is in keeping with another study looking at amniotic fluid IL-6, which compared TTTS pregnancies treated with laser with singleton pregnancies undergoing amniocentesis for karyotyping [15] and did not find a significant difference either. It is acknowledged that a type 2 error is possible given the small numbers studied.…”

“…It does not appear that FLA provokes a significant cytokine response. We do not believe that we have simply failed to detect changes, as the assays we used provided sensitivities for cytokines akin to levels reported by previous studies [15,16,31,32]. It is acknowledged that where differences are not found with multiplex assays it may be worthwhile conducting ELISA testing to confirm these findings and that the number of twin pregnancies studied was small, so a type 2 error is possible.…”

“…IL-6, IL-1β) expressed and produced by the decidua and fetal membranes are associated with spontaneous preterm labour and the associated reaction when infection is also implicated in this process [14]. IL-6 is one such cytokine, and this has also been investigated in relation to TTTS [15,16]. However, circulating cytokine concentrations in maternal plasma in MC twins in relation to TTTS have not been described.…”

Prenatal management and outcomes in mirror syndrome associated with twin–twin transfusion syndrome

“…Further studies have to be carried out to approve this hypothesis. Huber et al . found a significant correlation between the amount of amniotic fluid drained and the decrease in maternal Hb and Hct.…”

Amniodrainage-Induced Circulatory Dysfunction in Women Treated for Twin-To-Twin Transfusion Syndrome

“…In contrast to the high number of scientific reports on fetal outcome and treatment options, data on maternal hemodynamic changes or adverse side effects following FLA procedures are scarce. Clinical signs suggestive of maternal hemodilution were described in cases of mid-trimester TTTS managed by FLA and subsequent amniodrainage, providing evidence that such interventions have a significant impact on the maternal compartment [ 5 , 6 , 7 ]. A variety of observations including maternal hemodynamic adaptations, decrease in intrauterine pressure and increase in placental volume have been described following high volume amniodrainage [ 8 , 9 ].…”