Challenges for better care based on the course of maternal body mass index, weight gain and multiple outcome in twin pregnancies: a population-based retrospective cohort study in Hessen/Germany within 15 years

Abstract

Introduction: Studies on maternal weight, gestational weight gain and associated outcomes in twin pregnancies are scarce. Therefore, we analyzed these items in a large cohort.

Methods: Data from 10,603/13,725 total twin pregnancies from the perinatal database in Hessen, Germany between 2000 and 2015 were used after exclusion of incomplete or non-plausible data sets. The course of maternal and perinatal outcomes was evaluated by linear and logistic regression models.

Results: The rate of twin pregnancies increased from 1.5 to 1.9% (p < 0.00001). Mean maternal age and pre-pregnancy weight rose from 31.4 to 32.9 years and from 68.2 to 71.2 kg, respectively (p < 0.001). The rates of women with a body mass index ≥ 30 kg/m² increased from 11.9 to 16.9% with a mean of 24.4-25.4 kg/m² (p < 0.001). The overall increase of maternal weight/week was 568 g, the 25th quartile was 419, the 75th quartile 692 g/week. The total and secondary caesareans increased from 68.6 to 73.3% and from 20.6 to 39.8%, respectively (p < 0.001). Rates of birthweight < 1500 g and of preterm birth < 28 and from 28 to 33 + 6 weeks all increased (p < 0.01). No significant changes were observed in the rates of stillbirth, perinatal mortality and NICU admissions.

Conclusion: The global trend of the obesity epidemic is equally observed in German twin pregnancies. The increase of mean maternal weight and the calculated quartiles specific for twin pregnancies help to identify inadequate weight gain in twin gestations. Policy makers should be aware of future health risks specified for singleton and twin gestations.

Keywords: Caesarean delivery; Gestational weight gain; Obesity; Preterm delivery; Twin pregnancy.

Fig. 1

Course of twin pregnancy rates in Hessen 2000–2015, twins = number of twin pairs, total = total deliveries, n = 13,725/805,536 deliveries, p < 0.00001+, statistical analyses according to logistic regression

Fig. 2

Course of maternal outcomes between 2000 and 2015, n = 10,603, total = total twin deliveries, cases = absolute incidence of specific outcome, + = positive correlation, − = negative correlation, statistical analysis by linear (a, b) or logistic (c, d) regression. a Mean maternal age (years): p < 0.0001+, b mean maternal weight gain/gestational week (kg/week): p = 0.001+, c maternal body mass index categories (%) at 1st examination (< 14 gestational weeks): underweight: n = 324, p = 0.14; normal weight: n = 6321, p = 0.11; overweight: n = 2489, p = 0.62; obese: n = 1469, p < 0.001+, d hypertensive disorders in pregnancy (%): n = 743, p = 0.77

Fig. 3

Course of caesarean deliveries and postpartum haemorrhage between 2000 and 2015, n = 10,603, total = total twin deliveries, cases = absolute incidence of specific outcome, + = positive correlation, − = negative correlation all statistical analyses by logistic regression. a Total caesarean delivery (%): n = 7814, p < 0.001+, b secondary caesarean delivery (%): n = 3 005, p < 0.001+, *data from 2007 was excluded due to missing values. c Emergency caesarean delivery (%): n = 188, p = 0.93 (no data available in 2000). d Postpartum haemorrhage > 1000 ml (%): n = 237, p = 0.12

Fig. 4

Course of neonatal outcomes (I) between 2000 and 2015, n = 21,206, total = total twin deliveries (a) or newborn twins (b–d), cases = absolute incidence of specific outcome, + = positive correlation, − = negative correlation, all statistical analyses by logistic regression. a Preterm deliveries (%) in categories: delivery < 28 weeks: n = 520, p < 0.01+; delivery between 28 + 0 and 33 + 6 weeks: n = 3301, p = 0.002+; delivery between 34 + 0 and 36 + 6 weeks: n = 8548, p < 0.001−. b Birth weight (%) in categories: < 1500 g: n = 1860, p < 0.001+; 1500–1999 g: n = 2941, p = 0.41; 2000–2499 g: n = 6903, p = 0.07; 2500–2999 g: n = 6958, p = 0.33; > 3000 g: n = 2413, p = 0.50. c Stillbirth (%): n = 155, p = 0.85. d Perinatal mortality (%): n = 221, p = 0.82

Fig. 5

Course of neonatal outcomes (II) between 2000 and 2015, n = 21 206, total = total newborn twins, cases = absolute incidence of specific outcome, + = positive correlation, − = negative correlation, all statistical analyses by logistic regression. a NICU admissions (%): n = 9213, p = 0.28. b Newborns with an APGAR below 7 after 5 min (%): n = 633, p = 0.16. c Newborns with a pH in the umbilical artery below 7.1 (%): n = 370, p = 0.03+. d Newborns with an APGAR 5′ below 7 and a pH in the umbilical artery below 7.1 (%): n = 53, p = 0.39