Risk factors and perinatal outcomes of re-recurrent gestational diabetes mellitus: a retrospective cohort study in china

Objective: To explore the risk factors and perinatal outcomes of re-recurrent gestational diabetes mellitus (GDM). Methods: A retrospective cohort study of women with recurrent GDM who had two consecutive singleton deliveries was performed in Fujian Maternity and Child Health Hospital from January 1, 2012 and December 31, 2021. Datas on pregnancy characters and complications, neonatal and delivery outcomes were collected and analyzed. Results: (1) In total, 712 women were included and followed up. 90 women were excluded due to lack of oral glucose tolerance test after six weeks of postpartum and 13 women were lost in the follow up. As of the date of data cutoff, 94 women got third pregnancy and 46 of them delivered after 24 weeks . Among these 46 women , 32 (71.11%) complicated with GDM (case group) , 10 (21.74%) uncomplicated with GDM ( control group) and the other 4 (8.70%) women complicated with pre-gestational diabetes mellitus (PGDM) in the third pregnancy . (2) There was no significant difference in age, lover age, qualifications, gravidity, parity, mode of conception, history of macrosomia , pre-pregnancy BMI and gestational weight gain between two groups (all P ˃0.05). Interpregnancy interval (IPI) (months) to first (55.03±5.79 vs 69.10±3.14, P =0.000) and second (25.78±6.75 vs 41.30±5.95, P =0.000) pregnancy were significantly shorter in case group than control group. (3) OGTT 0 hPG and OGTT 1hPG during second pregnancy , TG before second delivery and FPG in first trimester showed no significant difference between two groups (all P ˃0.05) . OGTT 2 hPG (8.94±1.25 vs 7.91±1.12, P =0.026 ), number of OGTT abnormal items (1.91±0.77 vs 1.40±0.52, P =0.027) , TC before second deliveryand glycosylated (6.82±1.03 vs 6.10±0.73, P =0.046) and hemoglobin A1c (HbA1c) in second trimester (5.62±0.39 vs 5.33±0.20, P =0.031) and before delivery (5.72±0.38 vs 5.13±0.30, P =0.000) during second pregnancy was significantly higher in case group than control group . TG (2.29±0.54 vs 1.85±0.41, P =0.021) and TC (5.12±0.67 vs 3.92±0.30, P =0.000) in first trimester and FPG before delivery (5.12±0.74 vs 4.17±0.38, P =0.000) was significantly higher in case group than control group. (4) There was no significant difference in the hospitalization days and expenses, gestational age, mode of delivery ,Apgar score at 1 min, weight of fetus and the rate of hypertensive disorders in pregnancy (HDP) , intrahepatic cholestasis of pregnancy (ICP), premature rupture of membranes (PROM) , precipitate labor, postpartum hemorrhage (PPH) , small for gestational age (SGA) between two groups (all P ˃0.05). The rate of hypothyroidism in (34.38% vs 0%, P =0.31) case group were significantly higher than control group. The rate of large for gestational age (LGA) (28.13% vs 0%, P =0.058) and admission to NICU (34.38% vs 10.00%, P =0.14) in case group were higher than control group, but there was no statistically difference. Conclusions: Perinatal care for women with history of GDM especially recurrent GDM must be started before pregnancy and after delivery. It is recommended to choose the appropriate length of IPI and control the plasm level of lipid and glucose to minimize the high risk of re-recurrent GDM . The management of plasm lipid and glucose still need to be further strengthened and studied to improve the prognosis of perinatal outcomes.