Monochorionic triplet pregnancies occur in 1 to 4 per 100,000 pregnancies (Enzetami et al., Reference Enzetami, Runkel, Becker, Weitzel and Arabin1997; Ghulmiyyah et al., Reference Ghulmiyyah, Perloe, Tucker, Zimmermann, Eller and Sills2003; Imaizumi, Reference Imaizumi2003). Twin–twin transfusion syndrome (TTTS) can occur between twin pairs in monochorionic triplet pregnancies (Jain & Fisk, Reference Jain and Fisk2004). We present a case of TTTS in a monochorionic triamniotic pregnancy treated with laser photocoagulation. To our knowledge, this is the first reported case of twin anemia–polycythemia sequence (TAPS) in a pair of monochorionic triplets after laser photocoagulation for TTTS in a triplet pregnancy.
Case Report
A 37-year-old woman with a monochorionic triamniotic pregnancy presented with TTTS between triplets 1 and 2 on ultrasound scan at 193/7 weeks gestation. TTTS was diagnosed on the basis of oligohydramnios (maximal vertical pocket [MVP] of 1.7 cm) in triplet 1 and polyhydramnios (MVP = 8 cm) in triplet 2. The umbilical artery (UA), middle cerebral artery (MCA), and ductus venosus (DV) Doppler waveforms were normal for all triplets.
Three amnioreductions were performed at 205/7, 221/7, and 241/7 weeks from triplet 2 (1,500 mL, 1,250 mL, and 1,250 mL). Placental laser photocoagulation was performed at 243/7 weeks due to rapid progression from stage 1 to stage 3 TTTS between triplets 1 and 2, with normal MCA peak systolic velocities in all triplets and deep ‘a’ waves in triplet 2. The procedure was technically challenging due to the large anterior placenta and fetal positions. All anastomoses between triplets 1 and 2 and triplets 2 and 3 that were identified were photocoagulated (Dornier Medilas D SkinPulse S Class IV Diode Laser). At completion of the procedure, an amnioreduction was performed from triplet 2 (2,250 mL) reducing the MVP to 3 cm. All triplets were alive at the end of the procedure. The following day fetal demise of triplet 1 was identified on ultrasound scan. Triplets 2 and 3 had normal UA, MCA, and DV Doppler waveforms.
At 261/7 weeks, an ultrasound scan found discordant amniotic fluid volumes in the surviving triplets (triplet 2 MVP = 4.8 cm, triplet 3 MVP = 0.8 cm). The UA and MCA were normal for both surviving triplets. Three days later at 264/7 weeks, ultrasound demonstrated TAPS between the surviving triplets (triplet 2 MCA peak systolic velocity [-PSV] 77.5 cm/s, triplet 3 MCA-PSV 16 cm/s). Furthermore, triplet 2 had an elevated UA systolic–diastolic (S/D) ratio (3.9) and the DV had deep ‘a’ waves. Triplet 3, who had oligohydramnios (MVP = 0.8 cm) 3 days earlier, now had an MVP of 3 cm and a large fetal bladder.
Betamethasone was administered and the triplets were delivered by caesarean section.
Triplet 2 (905 gram) and triplet 3 (945 gram) were born in good condition with normal Apgar scores and normal umbilical cord blood gas results. Triplet 2 was found to have a hemoglobin of 68 g/L and a hematocrit of 0.21 and triplet 3 had a hemoglobin of 216 g/L and a hematocrit of 0.66. Triplet 2 required ventilation for 3 weeks, continuous positive airway pressure (CPAP) ventilation for 6 weeks, surfactant for hyaline membrane disease and four top-up transfusions for anemia. Triplet 2 also had a patent ductus arteriosus but had no evidence of retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH), or any other white-matter abnormalities on any of the postnatal ultrasound scans. Triplet 3 required ventilation for 3 weeks, CPAP for 8 weeks and surfactant for hyaline membrane disease. Similar to triplet 2, triplet 3 had no evidence of ROP, IVH, or other white-matter abnormalities on any postnatal imaging.
Triplet 2 was discharged on day 111 and triplet 3 was discharged on day 90 of life. Both triplets were discharged in good condition.
Discussion
Monochorionic triplet pregnancies are rare (Enzetami et al., Reference Enzetami, Runkel, Becker, Weitzel and Arabin1997; Ghulmiyyah et al., Reference Ghulmiyyah, Perloe, Tucker, Zimmermann, Eller and Sills2003; Imaizumi, Reference Imaizumi2003). Since 2005, to our knowledge, there have been five reported cases of monochorionic triplet pregnancies in Western Australia. As there are approximately 25,000 births a year, the incidence of monochorionic triplet births in Western Australia is approximately 1 in 125,000.
TTTS is an antenatal complication of monochorionic multiple gestation pregnancies (Ling et al., Reference Ling, Leo, Rodis and Campbell2000). TTTS is diagnosed by the presence in the mid-trimester of oligohydramnios (MVP < 2 cm) in one fetus and polyhydramnios (MVP > 8 cm) in the other fetus (Jain & Fisk, Reference Jain and Fisk2004). Although the pathogenesis of TTTS is not fully understood, it is thought to result from arterio-venous anastomoses in the placental bed (Jain & Fisk, Reference Jain and Fisk2004).
The rate of TTTS in monochorionic triplet pregnancies is unknown (Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005), while in monochorionic twin pregnancies the incidence is 15% (Sebire et al., Reference Sebire, Souka, Skentou and Nicolaides2000). Previous studies have demonstrated high rates of morbidity and mortality associated with TTTS in monochorionic triplet pregnancies (Adegbite et al., Reference Adegbite, Ward and Bajoria2005; Enzetami et al., Reference Enzetami, Runkel, Becker, Weitzel and Arabin1997; Fisk et al., Reference Fisk, Borrell, Hubinont, Tannirandorn, Nicolini and Rodeck1990; Hayashi et al., Reference Hayashi, Kikuchi, Joshita, Yasuhiro, Tatematsu, Horikoshi and Unno2005; Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Leung et al., Reference Leung, Wong, Leung, Lee, Tang and Lao2003; Ling et al., Reference Ling, Leo, Rodis and Campbell2000; Pons et al., Reference Pons, Olivennes, Fernandez, Ramdin, Mayenga, Bessis and Papiernik1990; Rehan et al., Reference Rehan, Menticoglou, Seshia and Bowman1995). Expectant management (Enzetami et al., Reference Enzetami, Runkel, Becker, Weitzel and Arabin1997; Fisk et al., Reference Fisk, Borrell, Hubinont, Tannirandorn, Nicolini and Rodeck1990; Pons et al., Reference Pons, Olivennes, Fernandez, Ramdin, Mayenga, Bessis and Papiernik1990), termination of pregnancy (Chasen et al., Reference Chasen, Al-Kouatly, Ballabh, Skupski and Chervenak2002; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010), amnioreduction (Adegbite et al., Reference Adegbite, Ward and Bajoria2005; Chasen et al., Reference Chasen, Al-Kouatly, Ballabh, Skupski and Chervenak2002; Hayashi et al., Reference Hayashi, Kikuchi, Joshita, Yasuhiro, Tatematsu, Horikoshi and Unno2005; Leung et al., Reference Leung, Wong, Leung, Lee, Tang and Lao2003; Ling et al., Reference Ling, Leo, Rodis and Campbell2000; Rehan et al., Reference Rehan, Menticoglou, Seshia and Bowman1995), and laser photocoagulation (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010; Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005; Van Shoubroeck et al., Reference Van Shoubroeck, Lewi, Ryan, Carreras, Jani, Higueras and Gratacos2004) have been reported to treat these pregnancies.
Our case demonstrated the failure of conservative management in TTTS in a triplet pregnancy and a 2-week prolongation of pregnancy following laser photocoagulation. Laser photocoagulation for TTTS in monochorionic twins has been strongly supported in clinical trials (Roberts et al., Reference Roberts, Gates, Kilby and Neilson2008; Rossi & D'Addario, Reference Rossi and D'Addario2008; Salomon et al., Reference Salomon, Ortqvist, Aegerter, Bussieres, Staracci, Stirnemann and Ville2010; Senat et al., Reference Senat, Deprest, Boulvain, Paupe, Winer and Ville2004). In a recent study of monochorionic twins with TTTS, laser photocoagulation was associated with improved survival and improved neurologic outcome (Ages and Stages Questionnaire) compared with amnioreduction at 6 years of age (Salomon et al., Reference Salomon, Ortqvist, Aegerter, Bussieres, Staracci, Stirnemann and Ville2010). There have been few studies exploring the role of laser photocoagulation or outcomes following treatment in monochorionic triplet pregnancies with TTTS (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010; Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005; Van Shoubroeck et al., Reference Van Shoubroeck, Lewi, Ryan, Carreras, Jani, Higueras and Gratacos2004). Chmait et al. (Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009) described the largest case series with six women with monochorionic triplets. In this report, the overall survival was 61% following laser photocoagulation, which was not different from the survival after amnioreduction (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009). Poor outcomes from laser photocoagulation reported in other studies (Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005) may be attributed to the technical difficulty and complexity of laser photocoagulation in monochorionic triplet pregnancies (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005; Van Shoubroeck et al., Reference Van Shoubroeck, Lewi, Ryan, Carreras, Jani, Higueras and Gratacos2004).
TAPS is a form of inter-twin transfusion characterized by a significant difference in hemoglobin level between twins without amniotic fluid discordance (Lopriore et al., Reference Lopriore, Middeldorp, Oepkes, Kanhai, Walther and Vandenbussche2007). In utero, this usually presents with increased MCA-PSV in one fetus, suggesting anemia, and reduced MCA-PSV in the other, suggesting polycythemia (Robyr et al., Reference Robyr, Lewi, Salomon, Yamamoto, Bernard, Deprest and Ville2006). There has been one reported case of TAPS in a monochorionic triplet pregnancy (Lopriore et al., Reference Lopriore, Middeldorp, Oepkes, Kanhai, Walther and Vandenbussche2007), but no reported cases of both TTTS and TAPS between pairs of monochorionic triamniotic triplets.
TAPS may occur following laser photocoagulation for TTTS, as in this case, or spontaneously in uncomplicated monochorionic pregnancies (Lopriore et al., Reference Lopriore, Middeldorp, Oepkes, Kanhai, Walther and Vandenbussche2007). It is reported to occur in up to 13% of cases following laser photocoagulation (Robyr et al., Reference Robyr, Lewi, Salomon, Yamamoto, Bernard, Deprest and Ville2006). There are currently no guidelines for the management of TAPS, but management options include expectant management, repeat laser photocoagulation, intrauterine transfusion, or selective feticide (Lopriore et al., Reference Lopriore, Hecher, Vandenbussche, van den Wijngaard, Klumper and Oepkes2008). In our case, the triplets were managed by prompt delivery.
Conclusion
In conclusion, monochorionic triamniotic pregnancies are rare and high risk (Adegbite et al., Reference Adegbite, Ward and Bajoria2005; Enzetami et al., Reference Enzetami, Runkel, Becker, Weitzel and Arabin1997; Fisk et al., Reference Fisk, Borrell, Hubinont, Tannirandorn, Nicolini and Rodeck1990; Hayashi et al., Reference Hayashi, Kikuchi, Joshita, Yasuhiro, Tatematsu, Horikoshi and Unno2005; Imaizumi, Reference Imaizumi2003; Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Leung et al., Reference Leung, Wong, Leung, Lee, Tang and Lao2003; Ling et al., Reference Ling, Leo, Rodis and Campbell2000; Pons et al., Reference Pons, Olivennes, Fernandez, Ramdin, Mayenga, Bessis and Papiernik1990; Rehan et al., Reference Rehan, Menticoglou, Seshia and Bowman1995). The invasive management of TTTS in monochorionic triplet pregnancies with laser photocoagulation bears the risk of intra-uterine death (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010; Ishii et al., Reference Ishii, Murakoshi, Numata, Kikuchi, Takakuwa and Tanaka2006; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005; Van Shoubroeck et al., Reference Van Shoubroeck, Lewi, Ryan, Carreras, Jani, Higueras and Gratacos2004) and TAPS (Lopriore et al., Reference Lopriore, Middeldorp, Oepkes, Kanhai, Walther and Vandenbussche2007; Robyr et al., Reference Robyr, Lewi, Salomon, Yamamoto, Bernard, Deprest and Ville2006). Laser photocoagulation is technically challenging in these pregnancies (Chmait et al., Reference Chmait, Kontopoulos, Bornick, Maitino and Quintero2009; Diemert et al., Reference Diemert, Diehl, Huber, Glosemeyer and Hecher2010; Sepulveda et al., Reference Sepulveda, Surerus, Vandecruys and Nicolaides2005; Van Shoubroeck et al., Reference Van Shoubroeck, Lewi, Ryan, Carreras, Jani, Higueras and Gratacos2004) and is best performed by teams with extensive experience in the treatment of TTTS in monochorionic twin pregnancies. In our case, the relatively good outcome of triplets 2 and 3 at short-term follow-up suggests the potential role of laser photocoagulation in similar cases in the future. Monochorionic triamniotic pregnancies should be managed in a tertiary setting with frequent ultrasound assessment due to the possibility of rapid changes in the condition of the triplets as the pregnancy progresses.
Disclosure of Interests
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
Acknowledgments
We thank the medical and midwifery staff members of King Edward Memorial Hospital, Perth, Western Australia.
