Screening blood donors for malaria, can we increase the number of eligible donors? An observational retrospective study.

BACKGROUND: In non-endemic countries, malaria can be transmitted through blood donations from imported cases. To ensure standards of quality and safety of human blood, the European Union and Spanish national law, requires a deferral period, or a screening by immunological or genomic test among those donors with potential risk of malaria. Scientific societies, European Committee on Blood Transfusion, and Spanish Society of Haematology and Haemotherapy, refer only to the result of the immunological test. METHODS: An observational retrospective study was performed in potential donors with a positive immunological test for malaria done in the Regional Transfusion Center in Madrid and referred to the National Reference Unit for Tropical Diseases in Madrid between 2015-2020. At consultation a Polymerase Chain Reaction (PCR) for malaria was performed. RESULTS: During the study period, 121 possible donors attended for consultation at NRU-Trop. Median age: 38.5 (IQR:33-48); median time to consultation was 32 months (IQR:12.5-110). Eighty-two (67.8%) donors were migrants and thirty-nine were travellers (32.2%). ELISA values were available for 109 subjects (90.1%), 56 individual left malaria endemic area > 3 years before. All donors tested negative for Plasmodium spp PCR test (n = 121, 100%). CONCLUSIONS: None of the subjects with a positive immunologic test deferred as blood donors had a positive genomic test. The presence of Plasmodium spp in collected blood was not detected by molecular techniques. To avoid the loss of potential blood donors, especially those with low incidence red blood cell antigens, as more precise microbiology techniques become available, updating the existing legislation becomes necessary to increase the availability of donated blood.

Maternal and perinatal outcomes in twin pregnancies following assisted reproduction: a systematic review and meta-analysis involving 802 462 pregnancies.

BACKGROUND: ART is associated with higher rates of twin pregnancies than singleton pregnancies. Whether twin pregnancies conceived following ART have additional maternal and neonatal complications compared with non-ART twin pregnancies is not known. OBJECTIVE AND RATIONALE: The objective was to quantify the risk of adverse maternal and perinatal outcomes among twin pregnancies conceived following ART compared with non-ART and natural conception. Existing reviews vary in the reported outcomes, with many studies including triplet pregnancies in the study population. Therefore, we aimed to perform an up-to-date review with an in-depth analysis of maternal and perinatal outcomes limited to twin pregnancies. SEARCH METHODS: We searched electronic databases MEDLINE and EMBASE from January 1990 to May 2023 without language restrictions. All cohort studies reporting maternal and perinatal outcomes following ART compared with non-ART twin pregnancies and natural conception were included. Case-control studies, case reports, case series, animal studies, and in vitro studies were excluded. The Newcastle-Ottawa Scale was used to assess the methodological quality of the studies. Using random-effects meta-analysis, the estimates were pooled and the findings were reported as odds ratios (OR) with 95% CI. OUTCOMES: We included 111 studies (802 462 pregnancies). Twin pregnancies conceived following ART were at higher risk of preterm birth at <34 weeks (OR 1.33, 95% CI 1.14-1.56, 29 studies, I2 = 73%), <37 weeks (OR 1.26, 95% CI 1.19-1.33, 70 studies, I2 = 76%), hypertensive disorders in pregnancy (OR 1.29, 95% CI 1.14-1.46, 59 studies, I2 = 87%), gestational diabetes mellitus (OR 1.61, 95% CI 1.48-1.75, 51 studies, I2 = 65%), and caesarean delivery (OR 1.80, 95% CI 1.65-1.97, 70 studies, I2 = 89%) compared with non-ART twins. The risks for the above maternal outcomes were also increased in the ART group compared with natural conception. Of the perinatal outcomes, ART twins were at significantly increased risk of congenital malformations (OR 1.17, 95% CI 1.05-1.30, 39 studies, I2 = 59%), birthweight discordance (>25% (OR 1.31, 95% CI 1.05-1.63, 7 studies, I2 = 0%)), respiratory distress syndrome (OR 1.32, 95% CI 1.09-1.60, 16 studies, I2 = 61%), and neonatal intensive care unit admission (OR 1.24, 95% CI 1.14-1.35, 32 studies, I2 = 87%) compared with non-ART twins. When comparing ART with natural conception, the risk of respiratory distress syndrome, intensive care admissions, and birthweight discordance >25% was higher among the ART group. Perinatal complications, such as stillbirth (OR 0.83, 95% CI 0.70-0.99, 33 studies, I2 = 49%), small for gestational age <10th centile (OR 0.90, 95% CI 0.85-0.95, 26 studies, I2 = 36%), and twin-twin transfusion syndrome (OR 0.45, 95% CI 0.25-0.82, 9 studies, I2 = 25%), were reduced in twin pregnancies conceived with ART versus those without ART. The above perinatal complications were also fewer amongst the ART group than natural conception. WIDER IMPLICATIONS: ART twin pregnancies are associated with higher maternal complications than non-ART pregnancies and natural conception, with varied perinatal outcomes. Women seeking ART should be counselled about the increased risks of ART twin pregnancies and should be closely monitored in pregnancy for complications. We recommend exercising caution when interpreting the study findings owing to the study's limitations.