The specific effects of gestational diabetes mellitus (GDM) on twin pregnancy outcomes, which are at high risk per se, are unclear. The present study analyzes outcomes of twin pregnancies complicated by GDM (n = 227) by comparing them with GDM singleton pregnancies (n = 1060) and with twin pregnancies without GDM (n = 1008), all followed up at Sant’Anna Hospital, Turin (Italy), between January 2010 and March 2020. The prevalence of GDM among twin pregnancies (n = 1235) was 18.4%. Compared to GDM singletons, GDM twins had higher rates of preeclampsia (aOR 2.0; 95% CI 1.2–3.8), cesarean section (aOR 7.5; 95% CI 5.2–10.8), and neonatal hypoglycemia (aOR 2.5; 95% CI 1.1–5.3). They had a higher incidence of abnormal 2 h OGTT values (aOR 7.1; 95% CI: 3.2–15.7) and were less likely to require insulin therapy (aOR 0.5; 95% CI: 0.3–0.7). In comparison with twin pregnancies without GDM, women with GDM twins were significantly older (35.0 vs. 33.0 years; p < 0.001) and had higher BMI (23.0 versus 22.0 kg/m²; p < 0.001); they had a higher incidence of LGA newborns (aOR 5.3; 95% CI 1.7–14.8), and lower incidence of low APGAR scores (0.5; 95% CI 0.3–0.9). Overall, GDM does not worsen outcomes of twin pregnancy, which is per se at high risk for adverse outcomes.

Background: Homocysteine (Hcy) plays a pivotal role in human reproduction, influencing gamete quality, embryo development, implantation, and pregnancy outcomes. It is central to folate and methionine metabolism and supports methylation-dependent epigenetic processes. Hyperhomocysteinemia (HHcy) exerts diverse biological effects and is associated with reproductive impairments in both sexes, affecting both spontaneous fertility and the outcome of assisted reproduction, including In Vitro Fertilization (IVF). Although the mechanisms of HHcy toxicity in reproduction are not fully understood, significant progress has been made in elucidating its effects. The emerging picture is complex, as Hcy and its metabolites impact biomolecules and cellular processes in a tissue- and sex-specific manner. Results: In men, HHcy compromises sperm deoxyribonucleic acid (DNA) integrity, methylation, and testicular microcirculation, reducing fertility potential. In women, HHcy disrupts follicular growth, oocyte competence, embryo quality, and endometrial receptivity, increasing the risk of implantation failure, miscarriage, and pregnancy complications. In assisted reproduction, HHcy and 5,10-methylenetetrahydrofolate reductase (MTHFR) variants may lower oocyte yield and embryo quality, although folate and B-vitamin supplementation can mitigate these effects. Conclusions: These effects largely reflect oxidative, inflammatory, vascular and epigenetic mechanisms, highlighting Hcy as a modifiable factor for improving natural fertility, optimizing IVF outcomes, and supporting healthy offspring development.

Background: Vitamin D deficiency is associated with several obstetric complications in singleton pregnancy. The aim of this study was to assess whether vitamin D levels affect the outcomes of twin pregnancy and if targeted supplementation can improve perinatal outcomes. Methods: The serum vitamin D levels of 143 women with twin pregnancies were measured during their first trimester. Those with insufficient (10–30 ng/mL; IL group) or severely deficient (30 ng/mL, SL group) since the beginning of pregnancy. Results: Women in the IL and DL groups had a higher incidence of hypertensive disorders of pregnancy (HDP) compared to the SL group (24.8% and 27.8% vs. 12.5%, p = 0.045): OR = 1.58 for the IL group and 1.94 for the DL group compared to the SL group. In patients whose vitamin D levels were restored after supplementation, HDP incidence was lower than in patients who remained in the IL or DL groups (23.4% vs. 27.3%) but higher than those who were always in the SL group (12.5%). Conclusions: Insufficient or severely deficient levels of vitamin D in the first trimester are associated with an increased risk of HDP in twin pregnancy. The beneficial effect of targeted vitamin D supplementation in reducing HDP seems limited.

Listeriosis is a rare but severe foodborne disease caused by Listeria Monocytogenes (LM), a small facultative intracellular bacillus. When occurring in pregnant women, it can be vertically transmitted to the fetus and the newborn. Infected women usually display aspecific and mild symptoms, and rarely develop the severe forms of the disease (such as neurolisteriosis). On the contrary, fetal and neonatal listeriosis can lead to complications such as fetal loss, preterm birth, neonatal sepsis, and respiratory distress syndrome (RDS). Prompt diagnosis is one of the main challenges because of the aspecific presentation of the disease; therapy relies on antibiotics that reach high intracellular concentration and can penetrate and pass the placenta reaching the fetus. Herein we report an infrequent case of LM infection involving a woman with monochorionic diamniotic twin pregnancy, followed by a comprehensive review of the available literature on listeriosis in pregnancy.

Objectives: Twin pregnancy implies a higher risk of preterm birth and, consequently, higher neonatal morbidity and mortality. In singleton pregnancies, infections of the lower genital tract (LGTIs) and bacterial vaginosis are associated with preterm labor, and their early detection has been proven effective in reducing complications like the preterm premature rupture of membranes (pPROM) and preterm delivery. The same evidence, however, is lacking for twin pregnancies. This study aimed to evaluate whether the early identification and treatment of LGTIs or bacterial vaginosis in asymptomatic women with twin pregnancy could reduce the rate of miscarriages, pPROM, and preterm birth. Methods: This study performed a retrospective comparison of 285 women with a multiple pregnancy submitted for a cervico-vaginal swab only at 20–22 weeks (Single Test Group, STG), and 199 women who underwent the swab at 12–14 and again at 20–22 weeks (Double Test Group, DTG). All women included in the study had a twin pregnancy and were followed up at Sant’Anna Hospital, Turin (Italy), between September 2012 and February 2021. Results: In STG, 21.7% of patients had a positive swab; in DTG, 19.9% had an early positive swab that was immediately treated by targeted antibiotics; and 16.7% had a mid-pregnancy positive swab. The DTG showed a significantly lower incidence of pPROM in univariate analysis (14.4% vs. 23.1%, p = 0.021), which was confirmed by multivariate analysis (OR 0.55, CI 0.33–0.93, p = 0.025). Conclusions: Our study suggests that, in asymptomatic women with twin pregnancy, the early screening of LGTIs and bacterial vaginosis by a cervico-vaginal swab at 12–14 weeks of gestational age is effective in reducing the risk of pPROM.

Objectives To compare outcomes of monochorionic diamniotic (MCDA) twin pregnancies by in vitro fertilization (IVF) vs. spontaneously conceived counterparts. Methods Retrospective comparison. Data about MCDA twin pregnancies, conceived spontaneously or by IVF, attending the Twin Pregnancy Care Unit of Sant’Anna Hospital in Turin (Italy) between January 1st 2010 and March 31st 2022, were collected retrospectively. Obstetric, fetal, and neonatal outcomes of MCDA twin pregnancies by IVF were compared to those of spontaneously conceived counterparts. Data were described by univariate and multivariate analysis. Results 541 MCDA twin pregnancies were included in the study, among which 45 conceived by IVF and 496 spontaneously conceived. Women with IVF twins were older than those who conceived spontaneously (36.7 ± 5.7 vs. 32.1 ± 5.2 years; p<0.001). No significant difference in the prevalence of pregnancy complications between the two groups was found, except for an increased incidence of hypertensive disorders among IVF pregnancies (17.8 vs. 8.5 %; p=0.039), which resulted nonsignificant after adjusting for maternal age and parity (aOR 1.9, 95 % CI 0.8–4.6). Data about 1,046 live born babies (90 conceived by IVF and 956 spontaneously) were also collected: perinatal outcomes did not differ between the two groups. Conclusions Our results suggest that MCDA twin pregnancies following IVF are not at increased risk of adverse outcomes compared to spontaneous MCDA twin pregnancies.