BackgroundTransient hyperprolactinemia was proven to adversely affect the outcome of IVF. We aimed to identify changes in serum prolactin levels in patients undergoing ICSI, and to evaluate the effect of these changes on the clinical pregnancy rate.MethodsA prospective observational study included 90 patients scheduled for ICSI cycles. In each case 4 serum samples were collected during the cycle (midluteal, before ovum pick up procedure (OPU), 2 h after OPU, and before embryo transfer). Serum prolactin level was determined by immunoassay each time.ResultsThe sample collected 2 h after OPU had a mean difference of 25.8 ± 2.8 ng/ml compared to the basal serum prolactin (p < 0.01). In comparison to other samples, this highlighted a significant hyperprolactinemia occurring after OPU, and resolving before embryo transfer. No statistically significant difference between the different serum prolactin samples amongst the pregnant and non pregnant patients. There was a significant positive pearson correlation between the prolactin levels before OPU, and the presence of higher quality embryos (r = 0.274, p = 0.019).ConclusionIn normoprolactinemic women transient hyperprolactinemia is identified in patients undergoing ICSI, and it doesn’t affect the clinical pregnancy rates. A positive correlation was identified between higher quality embryos, and serum prolactin level before OPU.Trial registrationClinicalTrials.gov Identifier: NCT02292953, First received: November 10, 2014.

The effects of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) and the NO donor sodium nitroprusside (SNP) on whole body O2 consumption (VO2) were assessed in 16 dogs anesthetized with fentanyl or isoflurane. Cardiac output (CO) and mean arterial pressure (MAP) were measured with standard methods and were used to calculate VO2 and systemic vascular resistance (SVR). Data were obtained in each dog under the following conditions: 1) Control 1, 2) SNP (30 microg. kg-1. min-1 iv) 3) Control 2, 4) L-NAME (10 mg/kg iv), and 5) SNP and adenosine (30 and 600 microg. kg-1. min-1 iv, respectively) after L-NAME. SNP reduced MAP by 29 +/- 3% and SVR by 47 +/- 3%, while it increased CO by 39 +/- 9%. L-NAME had opposite effects; it increased MAP and SVR by 24 +/- 4% and 103 +/- 11%, respectively, and it decreased CO by 37 +/- 3%. Neither agent changed VO2 from the baseline value of 4.3 +/- 0.2 ml. min-1. kg-1, since the changes in CO were offset by changes in the arteriovenous O2 difference. Both SNP and adenosine returned CO to pre-L-NAME values, but VO2 was unaffected. We conclude that 1) basally released endogenous NO had a tonic systemic vasodilator effect, but it had no influence on VO2; 2) SNP did not alter VO2 before or after inhibition of endogenous NO production; 3) the inability of L-NAME to increase VO2 was not because CO, i.e., O2 supply, was reduced below the critical level.