Associated perinatal determinants of vanishing twin pregnancies achieved by in vitro fertilization vs. spontaneous conception.

PURPOSE: To evaluate whether vanishing twin (VT) pregnancies following spontaneous conception have a more adverse perinatal outcome than those conceived after assisted reproduction techniques. METHODS: The retrospective cohort study consisted of 316 VT pregnancies derived from a hospital database between January 1994 and January 2016 (81 after IVF/ICSI and 235 after spontaneous conception). RESULTS: VT was significantly more prevalent after spontaneous conception (in 22.0% of twins) than after IVF/ICSI (in 14.5% of twins). VT pregnancies were significantly more associated with pre-gestational and gestational diabetes mellitus (GDM) in IVF/ICSI pregnancies compared to those spontaneously conceived [adjusted odds ratio (AOR): 4.12 and 11.1, respectively]. IVF-related placental insertion abnormalities were significantly higher in VT pregnancies. A high risk for VT was recorded in the spontaneous group for those who had previously undergone an induced abortion (AOR 0.56) or second-trimester fetal loss (AOR 0.67). The VT phenomenon was a major prognosticator of intrauterine growth retardation (IUGR) for the remaining fetus in IVF pregnancies (AOR 5.12). After controlling for covariates conjointly, advanced age (AOR 1.3), GDM (AOR 2.1), hypertensive disorders (AOR 3.5), primiparity (AOR 3.8), and placentation anomalies all represented independent risk factors for VT in IVF pregnancies. CONCLUSIONS: IVF/ICSI poses a higher risk for an adverse perinatal outcome following VT pregnancies as compared with those spontaneously conceived.

Prevalences and pregnancy outcome of vanishing twin pregnancies achieved by in vitro fertilization versus natural conception.

OBJECTIVE: To evaluate whether vanishing twin (VT) pregnancies achieved by in vitro fertilization and intracytoplasmic sperm injection (IVF-ICSI) had a more adverse perinatal outcome than those after natural conception. DESIGN: Longitudinal, retrospective cohort study. SETTING: Tertiary university hospital. PATIENT(S): Three hundred and six (78 after IVF-ICSI and 228 after natural conception) VT pregnancies over a 22-year period, with VT cases matched to primarily singleton controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Obstetric and neonatal outcome data. RESULT(S): The incidence of VT was statistically significantly higher after natural conception (18.2% of twins) than after IVF-ICSI (12.6% of twins). The odds of VT in pregnancies complicated with pregestational or gestational diabetes were disproportionally higher in IVF-ICSI cases than in spontaneously conceived VT pregnancies (adjusted odds ratio [AOR]: 0.80 vs. 3.10 and 1.00 vs. 1.07, respectively). Previous induced abortion (AOR 1.34) or second-trimester fetal loss (AOR 3.3) increased the risk of VT pregnancies after spontaneous conception. Gestational diabetes mellitus in both the previous (AOR 5.41) and the present (AOR 2.3) pregnancy as well as chronic maternal diseases (AOR 3.5) and placentation anomalies all represented independent risk factors for VT after IVF-ICSI. CONCLUSION(S): Vanishing twin pregnancies had a lower prevalence and a worse perinatal outcome after IVF-ICSI as compared with those of their spontaneously conceived counterparts.

Pregnancy Rate after Controlled Ovarian Hyperstimulation and Intrauterine Insemination for the Treatment of Endometriosis following Surgery.

OBJECTIVE: To compare pregnancy rate after controlled ovarian hyperstimulation and intrauterine insemination (COH-IUI) with no treatment in patients with endometriosis-associated infertility treated with laparoscopy. DESIGN: A clinical cohort study. SETTING: University-level tertiary care center. PATIENTS: 238 women with various stages of endometriosis after laparoscopic treatment. INTERVENTIONS: Either COH-IUI or follow-up for 12 months. MAIN OUTCOME MEASURES: The primary outcome measures were clinical pregnancy and live birth rate. Predictive factors evaluated were female age, maternal BMI, and duration of infertility. RESULTS: The pregnancy rate attained after the integrated laparoscopy-COH-IUI approach was 53.4%, while it was significantly lower (38.5%) in the control group. Similarly, a significant difference was observed in live births (48.3% versus 34.2%). Patients with severe endometriosis were less likely to achieve pregnancy (38%) and live birth (35%) than their counterparts with milder forms (57% and 53%). CONCLUSIONS: In patients with endometriosis-based infertility, surgery followed by COH-IUI is more effective than surgery alone.