Preconception Optimization of Glucose and Insulin Metabolism in Women Wanting to Conceive – High Rate of Spontaneous Conception Prior to Planned Assisted Reproduction

BACKGROUND: A hyperglycemic metabolic status with insulin resistance can have a negative effect on fertility and pregnancy outcomes. The aim of this retrospective study was to investigate disorders of glucose and insulin metabolism in women wanting to conceive who conceived spontaneously prior to planned assisted reproduction (ART). Associated risk factors of patients in terms of live births and miscarriages were also analyzed. METHOD: Out of total study population of 589 pregnancies, the pregnancies of 129 women wishing to have children who conceived spontaneously prior to planned ART were analyzed in more detail. A 75 g OGTT (OGTT: oral glucose tolerance test) was carried out prior to conception and after determination of pregnancy, including glucose measurement and testing of insulin resistance. If anomalies or risk factors for gestational diabetes (GDM) were detected, patients received metformin therapy prior to conception (off-label use). The course and outcome of pregnancies in the defined cohort were recorded. RESULTS: The rate of spontaneous conception before planned ART after treatment for disorders of glucose/insulin metabolism was 21.9% (n = 129/589). 66.7% of the 129 pregnancies resulted in a live birth, 32 patients had a miscarriage. 76.0% of patients were treated with metformin (off-label use) for polycystic ovary syndrome (PCOS), positive risk profile for GDM, or abnormal glucose/insulin metabolism prior to conception. 55.8% of the cohort developed GDM. The insulin requirements of patients with GDM differed significantly depending on their metformin intake. 24.6% of GDM patients receiving metformin treatment developed GDM requiring insulin treatment compared to 53.8% who did not receive metformin medication. The PCOS rate in the study population who had live births was significantly higher (57.0%) than in the group who had miscarriages (31.3%). There were no significant differences with regard to rate of live births and rate of miscarriages with/without metformin treatment and GDM and metformin intake. CONCLUSION: The high rate of spontaneous conceptions in the cohort of women wishing to conceive emphasizes the importance of optimizing glucose/insulin metabolism prior to conception. The high rate of GDM in a cohort of pregnant women with a history of sterility also emphasizes the importance of expanding diagnostic testing for sterility to include the investigation of glucose metabolism and testing for insulin resistance. It is possible that PCOS patients in particular could benefit from treatment with metformin prior to conception, and this could explain the high rate of live births in this patient cohort.