J. Perinat. Med. 39 (2011) 437–440 • Copyright  by Walter de Gruyter • Berlin • Boston. DOI 10.1515/JPM.2011.048 2011/006 Article in press - uncorrected proof Gestational diabetes mellitus complicating twin pregnancies Teresinha Simo˜es 1 , Alexandra Queiro´s 1 , Lucia Correia 1 , Tiago Rocha 2 , Elsa Dias 1 and Isaac Blickstein 3, * 1 Department of Maternal-Fetal Medicine and Maternity Dr. Alfredo da Costa, Lisbon, Portugal 2 Department of Endocrinology, Faculdade de Cieˆncias Me´dicas Universidade Nova de Lisboa, Portugal 3 Department of Obstetrics and Gynecology, Kaplan Medical Center, Rehovot, The Hadassah-Hebrew University School of Medicine, Jerusalem, Israel Abstract Objective: To compare outcomes of twin pregnancies with and without gestational diabetes mellitus (GDM). Study design: We compared 105 twin pregnancies with GDM (7.8% of all twin pregnancies) to 315 controls without GDM, matched for gestational age, chorionicity and year of birth. Results: Pre-gravid obesity appears to predispose women to GDM during twin pregnancy w odds ratio (OR) 3.5; 95% con- fidence interval (CI) 1.7, 7.0x . Overweight and obese women that subsequently developed GDM during their twin gesta- tion were less likely to conceive spontaneously (OR 0.4; 95% CI 0.3, 0.7). Twins from the GDM group had more respiratory distress syndrome (RDS, OR 2.2; 95% CI 1.3, 3.7) and had a three-fold, but not significantly increased per- inatal mortality rate. Birth weight characteristics were similar in both groups. Conclusion: Twin pregnancies complicated by GDM might be associated with pre-pregnancy maternal obesity and are at increased risk of RDS and non-significant increased risk of perinatal death. Keywords: Gestational diabetes; obesity; respiratory distress syndrome; twin pregnancy. Introduction Gestational diabetes mellitus (GDM) is a relatively common disease. Much information on the clinical significance of GDM in singleton pregnancies but relatively little informa- *Corresponding author: Isaac Blickstein, MD Department of Obstetrics and Gynecology Kaplan Medical Center 76100 Rehovot Israel Tel.: q972-545-201789 Fax: q972-89411944 E-mail: blick@netvision.net.il tion exists on the association between gestational diabetes and multiple pregnancy w 6x . It has been argued that multiple pregnancies are prone to GDM because of larger placental mass (hyperplacentosis), older age of expecting mothers of multiples, increased weight gain and body mass in twin ges- tations, and because of exaggerated response to fasting and food w 6x . Indeed, Simchen et al. w 12x showed that pregnancy in advanced maternal age after ovum donation had, among other complications, 31% of GDM. It also appears that a plurality-dependent frequency of GDM exists whereby GDM was significantly more frequent in triplets compared to (reduced) twins w 14x . At the same time, however, conflicting data exist concerning GDM and multiple pregnancies, whereby a similar prevalence of GDM was found in twin and singleton pregnancies, no difference was found in glu- cose challenge and tolerance tests between twin and single- ton pregnancies, and similar insulin requirements were found in twin and singleton pregnancies complicated by GDM w 6x . Irrespective of the conflicting views, the increasing num- bers of twin pregnancies and births observed in most devel- oped countries increases the number of expecting mothers of twins diagnosed with GDM. Moreover, the few quasi-epi- demiological studies describing the prevalence of GDM in twin gestations are quite old and presumably include few multiple pregnancies resulting from iatrogenic conceptions (i.e., after infertility treatment). Also, some bias exists which overlooks changes in management over time. For example, it would be interesting to know how recommendations for excess weight gain during early stages of a multiple preg- nancy would influence carbohydrate metabolism w 9x . It is also striking that data concerning the effect of GDM on perinatal outcome in multiple pregnancies are very scant. Tchobroutsky et al. w 15x reported on a high-frequency of fetal malformations in type I diabetic women with twin preg- nancies, however, the small number of cases precluded a final conclusion and are irrelevant for gestational diabetes. Keller et al. w 7x compared 13 twin pregnancies complicated with GDM to matched-by-gestational-age twin pregnancies. Within this very small sample size there was a trend of great- er likelihoods of respiratory distress syndrome (RDS), hyper- bilirubinemia and prolonged neonatal intensive care nursery admission in the diabetic group. More recently, Rauh-Hain et al. w 11x compared twin to singleton pregnancies and found that patients with twins had a two-fold increased risk of developing GDM. In terms of neonatal outcome, twins of gestational diabetics had a higher rate of admission to the neonatal intensive care unit, longer hospitalization, and higher risk of RDS. With these difficulties in mind, we conducted a case-con- trol study to examine the perinatal outcome related to the co-occurrence of GDM and twin gestations. Brought to you by | Simon Fraser University Authenticated Download Date | 6/3/15 6:34 PM