The quantitative knowledge of global forest litterfall is very important for understanding the global biogeochemical cycle and evaluating of forest ecosystem services. Our aims are to show the spatio‐temporal patterns of forest litterfall and the variation in different forest types and climate zones in the world. We compiled the global forest litterfall dataset of 2347 total litterfall and 1507 leaf litterfall measurements by a survey of literature published. The total litterfall and leaf litterfall were estimated in 2000 and 2009, respectively, through raster and vector calculation based on remote sensing‐based global vegetation cover data. The total litterfall and leaf litterfall were 31.5 Pg and 22 Pg in 2000 and 26 Pg and 18 Pg in 2009, respectively. The spatial pattern of litterfall and leaf litterfall at global scale between 2000 and 2009 was generally similar. The largest fractions of forest litterfall were in evergreen broadleaved forests (37%), followed by needle‐leaved forests (25%), deciduous broadleaved forests (20%), and others (18%) in 2000. The order of the fractions for forest litterfall was the tropical (50%), boreal (24%), temperate (17%), and subtropical forests (9%) in 2000. The ratios of leaf litterfall to litterfall were 70% in 2000 and 72% in 2009. The variability of global litterfall was most explained by the actual evapotranspiration. The reduction in total litterfall and leaf litterfall between 2000 and 2009 was coupled with the decrease in forest areas. The GIS‐based geostatistics combining with the regression model represents a powerful approach for estimating the global spatial distribution, composition, and magnitude of litterfall.

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Background: Previous studies have demonstrated that newborns from fresh embryo transfer have higher risk of small for gestation (SGA) rate than those from frozen-thawed embryo transfer (FET). It is suggested that supraphysiologic serum estradiol in controlled ovarian stimulation (COS) is one of reasons. Our study aims to investigate whether exogenous estradiol delivered regimens have an impact on live birth rate and neonatal outcomes in hormone replacement (HRT)-FET cycles. Methods: This was a retrospective study involving patients undergoing their first FET with HRT endometrium preparation followed by the transfer of two cleavage-staged embryos, comparing estradiol administered orally and vaginally (OVE group) versus estradiol administered orally (OE group) from January 2015 to December 2018 at our center. A total of 792 patients fulfilled the criteria, including 228 live birth singletons. The live birth rate was the primary outcome measure. Secondary outcome measures included clinical pregnancy rate, singleton birthweight, large for gestational age (LGA) rate, SGA rate, preterm delivery rate. Results: Patients in OVE group achieved higher serum estradiol level with more days of estradiol treatment. No difference in live birth (Adjusted OR 1.327; 95%CI 0.982, 1.794, p = 0.066) and clinical pregnancy rate (Adjusted OR 1.278; 95%CI 0.937, 1.743, p = 0.121) was found between OVE and OE groups. Estradiol route did not affect singletons birth weight (β = -30.962, SE = 68.723, p = 0.653), the odds of LGA (Adjusted OR 1.165; 95%CI 0.545, 2.490, p = 0.694), the odds of SGA (Adjusted OR 0.569; 95%CI 0.096, 3.369, p = 0.535) or the preterm delivery (Adjusted OR 0.969; 95%CI 0.292, 3.214, p = 0.959). Conclusion: Estrogen taken orally and vaginally together did not change live birth rate and singleton neonatal outcomes compared to estrogen taken orally, but was accompanied with relative higher serum E2 level and potential maternal undesirable risks.

Background The overall cumulative live birth rate (CLBR) of poor ovary responders (POR) is extremely low. Minimal ovarian stimulation (MOS) suggested a relative realistic solution in ART for POR. Our study aimed to investigate whether multiple MOS strategy results in higher CLBR compared to GnRH antagonist protocol and the cost-effectiveness analysis in POR. Methods This retrospective study involved 699 patients (1058 cycles) who fulfilled the Bologna criteria in one center performed from 2010–2018. Specifically, 325 women (325 cycles) were treated with one time conventional GnRH antagonist ovarian stimulation (GnRH-antagonist). Another 374 patients (733 cycles) were treated with multiple minimal ovarian stimulations (MOS) including natural cycles. CLBR and cost-effectiveness analysis were performed comparing these two groups of women. Results GnRH- antagonist leads to more oocytes retrieved, more fertilized oocytes and more viable embryos compared to first MOS (p < 0.001) and the cumulative corresponding ones in multiple MOS (p < 0.001). For the first IVF cycle, GnRH- antagonist results in higher CLBR than MOS (12.92% versus 4.54%, Adjusted OR 2.606; 95%CI 1.386, 4.899, p = 0.003). However, GnRH-antagonist induces comparable CLBR with multiple MOS (12.92% versus 7.92%, Adjusted OR 1.702; 95%CI 0.971, 2.982, p = 0.063), but absolutely shorter time to live birth (9 (8, 10.75) months versus 11 (9, 14) months, p = 0.014) and similar financial expenditure compared to repeated MOS (20838 (17953, 23422) ¥ versus 21261.5 (15892.5, 35140.25) ¥, p = 0.13). Conclusion Both MOS and GnRH-antagonist provide low chance of live birth for poor responders. GnRH antagonist protocol is a sound choice for POR with comparable CLBR, shorter time to live birth and similar financial expenditure.