Neutrophils to lymphocytes ratio (NLR) and platelets to lymphocytes ratio (PLR) are both inflammatory ratios that can be easily calculated from a simple blood count. They are frequently reported and tested as prognostic factors in several medical disciplines. Pregnancy involves special reference values for laboratory assays. The aim of this study was to define pregnancy-related reference values for NLR and PLR according to trimester, background morbidity and according to the patient's age. A retrospective analysis of a large cohort undergoing community-based pregnancy surveillance between the years 2011–2016. Data were analyzed according to high-risk patient versus normal-risk patient. A total of 11,415 patients were included. Mean PLR and NLR values were 136.3±44.3, 2.6±1, respectively during the first trimester, 144.6±47.1, 4.0±1.4 respectively during the second trimester and 118.1±42.0, 3.5±1.2 respectively during the third trimester. No difference was detected between the high-risk and the normal population (P-values 0.3, 0.5 and 0.4 for PLR in each trimester respectively and 0.3, 0.4, 0.6 for NLR in each trimester, respectively). No differences were detected among parity categories. The correlation between patient’s age and either PLR and NLR was a weak positive correlation (though statistically significant). Both PLR and NLR reached a maximum value during the second trimester. The differences between mean NLR and PLR between trimesters were significant (P <0.01 for all differences tested). PLR rises in the presence of anemia, reaching statistical significance (P-value for PLR in each trimester was <0.01). NLR showed an opposite trend (P-values for NLR were 0.4, 0.005 and 0.06 in each trimester, respectively). In our cohort, there were generally no differences between the high-risk and the normal population, excluding patients with a fibroid uterus or inflammatory bowel disease who presented a significantly elevated PLR through all trimesters. Both PLR and NLR reached a maximum value during the second trimester and were positively correlated with age. We anticipate that the population-based data will assist in providing accurate reference values for future research testing NLR and PLR measures during pregnancy.

Data collection regarding the effects of COVID-19 on reproduction is ongoing. This study examined the effect of COVID-19 on IVF cycle parameters and early pregnancy outcomes. It included two arms: the first compared non-exposed cycles to post-SARS-CoV-2 IVF cycles. Sperm parameters were also compared. The second, prospective arm compared pregnancy outcomes among IVF patients who contracted COVID-19 during early pregnancy to those who did not. None of the patients were vaccinated against SARS-CoV-2. The first arm included 60 treatment cycles of women with confirmed COVID-19, compared to 60 non-exposed cycles (either the same patient before exposure or matched non-exposed patients). The outcomes of the treatment cycles did not differ significantly between exposed and non-exposed groups, including number of oocytes, endometrial thickness, fertilization rate and number of top-quality embryos. In 11 cycles, the male partner had also recently recovered: sperm concentration was lower post-exposure: 6.27 million/mL vs. 16.5 pre-exposure (p = 0.008). In 189 patients with IVF-achieved pregnancies, pregnancy loss and hospital admissions did not differ between exposed and non-exposed groups. IVF treatment outcomes and the rate of early pregnancy loss appears to be unaffected by SARS-CoV-2 disease, despite a minor decline in sperm concentration among recent recoverees.

Human chorionic gonadotropin (hCG) is no longer a single, omnipotent ovulation triggering option. Gonadotropin releasing hormone (GnRH) agonist, initially presented as a substitute for hCG, has led to a new era of administering GnRH agonist followed by hCG triggering. According to this new concept, GnRH agonist enables successful ovum maturation, while hCG supports the luteal phase and pregnancy until placental shift.