Primary versus secondary recurrent pregnancy losses: Clinical findings and live birth rate after comprehensive work-up and personalized management.

Introduction: Recurrent pregnancy loss (RPL), defined as two or more consecutive pregnancy losses before 24 weeks of gestation, affects up to 1%-2% of couples. Aim of this retrospective cohort study was to report the main causes and pregnancy outcomes of a cohort of women with RPL and the efficacy of a personalized work-up and treatment in terms of live birth rate.

Material and methods: Women with primary (pRPL) and secondary (sRPL) RPL underwent a complete work-up and personalized therapeutic management. Data related to clinical findings and subsequent pregnancy outcomes were collected. A retrospective comparison between clinical findings and pregnancy outcomes of pRPL versus sRPL was performed by Mann-Whitney U or Chi-square test.

Results: Main findings after diagnostic work-up in pRPL (n = 157) versus sRPL (n = 138) couples were hormonal and metabolic factors (75% vs. 90%, p < 0.01), autoimmunity (52% vs. 59%, p = 0.2), acquired uterine/endometrial factors (43% vs. 34%, p = 0.2), vaginal and/or cervical infections (19% vs. 49%; p < 0.0001), congenital Mullerian anomalies (15% vs. 9%; p = 0.1), inherited thrombophilias (13% vs. 21%; p = 0.1), female karyotype abnormalities (2% vs. 2%; p = 0.9), sperm infections (27% vs. 22%; p = 0.1), abnormal semen analysis (17% vs. 14%; p = 0.1), male karyotype abnormalities (2% vs. 0%; p = 0.1). Higher pregnancy and fetal loss rate was observed in pRPL compared with sRPL (85% vs. 56%, p < 0.0001and 9% vs. 0%, p < 0.01, respectively). Higher live birth rate was found in pRLP versus sRPL women (76% vs. 56%, p < 0.001). Increased live birth rate was observed among pRPL women aged <40 years (OR 2.76; CI 1.36-5.64, p < 0.01) and/or with an AMH >1 ng/mL (OR 3.96; CI 1.34-12.52, p < 0.05). Among sRPL women, the age < 40 years was significantly associated to higher live birth rate (OR 3.23; 1.55-6.94, p < 0.01).

Conclusions: RPL is a heterogeneous multifactorial syndrome. A customized management can lead to a good pregnancy outcome in more than a half of cases. Age <40 and AMH >1 ng/mL are the major positive predictors of live birth rate in RPL women.