Physical development of preterm monochorionic diamniotic twins at birth: retrospective cohort study

Background. Much controversy surrounds the estimation of anthropometric parameters in multiple newborns. In newborn monochorionic diamniotic twins, these parameters can be affected by specific antenatal complications.

Objectives. To estimate the physical development parameters of preterm monochorionic diamniotic twins according to standards proposed within the INTERGROWTH-21st project, taking specific intrauterine complications into account.

Methods. The anthropometric data were analyzed in 148 pairs of newborn monochorionic diamniotic twins, who were divided into three groups according to the presence of specific intrauterine complications: Group I (n = 56 pairs) — twin-to-twin transfusion syndrome (TTTS); Group II (n = 38 pairs) — selective intrauterine growth restriction (sIUGR); Group III (n = 58 pairs) — absence of the above-mentioned specific complications. The obtained data were statistically processed on a personal computer via variation statistics methods using Microsoft Excel spreadsheets (Microsoft, USA) and an online service available at https://medstatistic.ru.

Results. Newborns with sIUGR (37–100.0%) and 26 (49.1%) donors fell into the category of newborns light for gestational age. Disharmonious (3–10th percentile) and markedly disharmonious (below the 3rd percentile) physical development at birth was most commonly observed in newborns with sIUGR and, to a lesser extent, in donors (OR — 9.2; 95% CI — 3.2–24.3; p < 0.05), which was noted only occasionally in monochorionic twins from other groups. A combined decrease in the values of birth centiles for head circumference, body weight, and body length was found in 13 (35.1%) newborns with sIUGR and in 12 (22.6%) donors, which may mark the severity of antenatal complications and the development of neurological deficit.

Conclusion. Monochorionic diamniotic twins include newborns having greater and lower body weights. In the newborn having a lower birth weight, specific complications associated with monochorionic multiple pregnancy result in body weight and length deficit, disharmonious development due to the lack of nourishment (22.6% in the TTTS group and 73.0% in the sIUGR group), as well as delayed head circumference growth in 56.8% of newborns with sIUGR.