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1.
BJOG ; 130(10): 1238-1246, 2023 09.
Article in English | MEDLINE | ID: mdl-37069731

ABSTRACT

OBJECTIVE: To examine internal organ tissues and placentas of stillbirths for various pathogens. DESIGN: Prospective, observational study. SETTINGS: Three study hospitals in India and a large maternity hospital in Pakistan. POPULATION: Stillborn infants delivered in a study hospital. METHODS: A prospective observational study. MAIN OUTCOME MEASURES: Organisms identified by pathogen polymerase chain reaction (PCR) in internal organs and placental tissues of stillbirths. RESULTS: Of 2437 stillbirth internal tissues, 8.3% (95% CI 7.2-9.4) were positive. Organisms were most commonly detected in brain (12.3%), cerebrospinal fluid (CSF) (9.5%) and whole blood (8.4%). Ureaplasma urealyticum/parvum was the organism most frequently detected in at least one internal organ (6.4% of stillbirths and 2% of all tissues). Escherichia coli/Shigella was the next most common (4.1% one or more internal organ tissue sample and 1.3% of tissue samples), followed by Staphylococcus aureus in at least one internal organ tissue (1.9% and 0.9% of all tissues). None of the other organisms was found in more than 1.4% of the tissue samples in stillbirths or more than 0.6% of the internal tissues examined. In the placenta tissue, membrane or cord blood combined, 42.8% (95% CI 40.2-45.3) had at least one organism identified, with U. urealyticum/parvum representing the most commonly identified (27.8%). CONCLUSIONS: In about 8% of stillbirths, there was evidence of a pathogen in an internal organ. Ureaplasma urealyticum/parvum was the most common organism found in the placenta and in the internal tissues, especially in the fetal brain.


Subject(s)
Placenta , Stillbirth , Infant , Pregnancy , Female , Humans , Stillbirth/epidemiology , Prospective Studies , Ureaplasma , Brain
2.
BJOG ; 129(4): 619-626, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34529344

ABSTRACT

OBJECTIVE: To evaluate the association between maternal fructosamine levels at the time of delivery and stillbirth. DESIGN: Secondary analysis of a case-control study. SETTING: Multicentre study of five geographic catchment areas in the USA. POPULATION: All singleton stillbirths with known diabetes status and fructosamine measurement, and representative live birth controls. MAIN OUTCOME MEASURES: Fructosamine levels in stillbirths and live births among groups were adjusted for potential confounding factors, including diabetes. Optimal thresholds of fructosamine to discriminate stillbirth and live birth. RESULTS: A total of 529 women with a stillbirth and 1499 women with a live birth were included in the analysis. Mean fructosamine levels were significantly higher in women with a stillbirth than in women with a live birth after adjustment (177 ± 3.05 versus 165 ± 2.89 µmol/L, P < 0.001). The difference in fructosamine levels between stillbirths and live births was greater among women with diabetes (194 ± 8.54 versus 162 ± 3.21 µmol/L), compared with women without diabetes (171 ± 2.50 versus 162 ± 2.56 µmol/L). The area under the curve (AUC) for fructosamine level and stillbirth was 0.634 (0.605-0.663) overall, 0.713 (0.624-0.802) with diabetes and 0.625 (0.595-0.656) with no diabetes. CONCLUSIONS: Maternal fructosamine levels at the time of delivery were higher in women with stillbirth compared with women with live birth. Differences were substantial in women with diabetes, suggesting a potential benefit of glycaemic control in women with diabetes during pregnancy. The small differences noted in women without diabetes are not likely to justify routine screening in all cases of stillbirth. TWEETABLE ABSTRACT: Maternal serum fructosamine levels are higher in women with stillbirth than in women with live birth, especially in women with diabetes.


Subject(s)
Fructosamine/blood , Stillbirth/epidemiology , Adult , Case-Control Studies , Causality , Female , Humans , Live Birth/epidemiology , Pregnancy , ROC Curve , Risk Factors , United States/epidemiology
5.
BJOG ; 128(11): 1762-1773, 2021 10.
Article in English | MEDLINE | ID: mdl-34173998

ABSTRACT

OBJECTIVE: Stillbirths occur 10-20 times more frequently in low-income settings compared with high-income settings. We created a methodology to define the proportion of stillbirths that are potentially preventable in low-income settings and applied it to stillbirths in sites in India and Pakistan. DESIGN: Prospective observational study. SETTING: Three maternity hospitals in Davangere, India and a large public hospital in Karachi, Pakistan. POPULATION: All cases of stillbirth at ≥20 weeks of gestation occurring from July 2018 to February 2020 were screened for participation; 872 stillbirths were included in this analysis. METHODS: We prospectively defined the conditions and gestational ages that defined the stillbirth cases considered potentially preventable. Informed consent was sought from the parent(s) once the stillbirth was identified, either before or soon after delivery. All information available, including obstetric and medical history, clinical course, fetal heart sounds on admission, the presence of maceration as well as examination of the stillbirth after delivery, histology, and polymerase chain reaction for infectious pathogens of the placenta and various fetal tissues, was used to assess whether a stillbirth was potentially preventable. MAIN OUTCOME MEASURES: Whether a stillbirth was determined to be potentially preventable and the criteria for assignment to those categories. RESULTS: Of 984 enrolled, 872 stillbirths at ≥20 weeks of gestation met the inclusion criteria and were included; of these, 55.5% were deemed to be potentially preventable. Of the 649 stillbirths at ≥28 weeks of gestation and ≥1000 g birthweight, 73.5% were considered potentially preventable. The most common conditions associated with a potentially preventable stillbirth at ≥28 weeks of gestation and ≥1000 g birthweight were small for gestational age (SGA) (52.8%), maternal hypertension (50.2%), antepartum haemorrhage (31.4%) and death that occurred after hospital admission (15.7%). CONCLUSIONS: Most stillbirths in these sites were deemed preventable and were often associated with maternal hypertension, antepartum haemorrhage, SGA and intrapartum demise. TWEETABLE ABSTRACT: Most stillbirths are preventable by better care for women with hypertension, growth restriction and antepartum haemorrhage.


Subject(s)
Fetal Death/prevention & control , Prenatal Care/statistics & numerical data , Quality of Health Care/statistics & numerical data , Stillbirth/epidemiology , Adult , Female , Gestational Age , Humans , India/epidemiology , Infant, Newborn , Infant, Small for Gestational Age , Obstetric Labor Complications/epidemiology , Pakistan/epidemiology , Pregnancy , Prenatal Care/standards , Prospective Studies
6.
BMC Public Health ; 21(1): 952, 2021 05 20.
Article in English | MEDLINE | ID: mdl-34016085

ABSTRACT

BACKGROUND: Improving maternal health has been a primary goal of international health agencies for many years, with the aim of reducing maternal and child deaths and improving access to antenatal care (ANC) services, particularly in low-and-middle-income countries (LMICs). Health interventions with these aims have received more attention from a clinical effectiveness perspective than for cost impact and economic efficiency. METHODS: We collected data on resource use and costs as part of a large, multi-country study assessing the use of routine antenatal screening ultrasound (US) with the aim of considering the implications for economic efficiency. We assessed typical antenatal outpatient and hospital-based (facility) care for pregnant women, in general, with selective complication-related data collection in women participating in a large maternal health registry and clinical trial in five LMICs. We estimated average costs from a facility/health system perspective for outpatient and inpatient services. We converted all country-level currency cost estimates to 2015 United States dollars (USD). We compared average costs across countries for ANC visits, deliveries, higher-risk pregnancies, and complications, and conducted sensitivity analyses. RESULTS: Our study included sites in five countries representing different regions. Overall, the relative cost of individual ANC and delivery-related healthcare use was consistent among countries, generally corresponding to country-specific income levels. ANC outpatient visit cost estimates per patient among countries ranged from 15 to 30 USD, based on average counts for visits with and without US. Estimates for antenatal screening US visits were more costly than non-US visits. Costs associated with higher-risk pregnancies were influenced by rates of hospital delivery by cesarean section (mean per person delivery cost estimate range: 25-65 USD). CONCLUSIONS: Despite substantial differences among countries in infrastructures and health system capacity, there were similarities in resource allocation, delivery location, and country-level challenges. Overall, there was no clear suggestion that adding antenatal screening US would result in either major cost savings or major cost increases. However, antenatal screening US would have higher training and maintenance costs. Given the lack of clinical effectiveness evidence and greater resource constraints of LMICs, it is unlikely that introducing antenatal screening US would be economically efficient in these settings--on the demand side (i.e., patients) or supply side (i.e., healthcare providers). TRIAL REGISTRATION: Trial number: NCT01990625 (First posted: November 21, 2013 on https://clinicaltrials.gov ).


Subject(s)
Cesarean Section , Developing Countries , Child , Female , Humans , Poverty , Pregnancy , Pregnant Women , Prenatal Care
7.
BJOG ; 128(9): 1487-1496, 2021 08.
Article in English | MEDLINE | ID: mdl-33629490

ABSTRACT

OBJECTIVE: Limited data are available from low- and middle-income countries (LMICs) on the relationship of haemoglobin levels to adverse outcomes at different times during pregnancy. We evaluated the association of haemoglobin levels in nulliparous women at two times in pregnancy with pregnancy outcomes. DESIGN: ASPIRIN Trial data were used to study the association between haemoglobin levels measured at 6+0 -13+6  weeks and 26+0 -30+0  weeks of gestation with fetal and neonatal outcomes. SETTING: Obstetric care facilities in Pakistan, India, Kenya, Zambia, The Democratic Republic of the Congo and Guatemala. POPULATION: A total of 11 976 pregnant women. METHODS: Generalised linear models were used to obtain adjusted relative risks and 95% CI for adverse outcomes. MAIN OUTCOME MEASURES: Preterm birth, stillbirth, neonatal death, small for gestational age (SGA) and birthweight <2500 g. RESULTS: The mean haemoglobin levels at 6+0 -13+6  weeks and at 26-30 weeks of gestation were 116 g/l (SD 17) and 107 g/l (SD 15), respectively. In general, pregnancy outcomes were better with increasing haemoglobin. At 6+0 -13+6  weeks of gestation, stillbirth, SGA and birthweight <2500 g, were significantly associated with haemoglobin of 70-89 g/l compared with haemoglobin of 110-129 g/l The relationships of adverse pregnancy outcomes with various haemoglobin levels were more marked at 26-30 weeks of gestation. CONCLUSIONS: Both lower and some higher haemoglobin concentrations are associated with adverse fetal and neonatal outcomes at 6+0 -13+6  weeks and at 26-30 weeks of gestation, although the relationship with low haemoglobin levels appears more consistent and generally stronger. TWEETABLE ABSTRACT: Both lower and some higher haemoglobin concentrations were associated with adverse fetal and neonatal outcomes at 6-13 weeks and 26-30 weeks of gestation.


Subject(s)
Hemoglobins/analysis , Infant, Small for Gestational Age , Perinatal Death , Premature Birth/epidemiology , Stillbirth/epidemiology , Adult , Developing Countries , Erythrocyte Indices , Female , Gestational Age , Humans , Pregnancy , Pregnancy Trimester, First , Risk Factors
8.
Plant Biol (Stuttg) ; 23(4): 556-563, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33550673

ABSTRACT

Floral structures, such as stamen appendages, play crucial roles in pollinator attraction, pollen release dynamics and, ultimately, the reproductive success of plants. The pollen-rewarding, bee buzz-pollinated flowers of Melastomataceae often bear conspicuous staminal appendages. Surprisingly, their functional role in the pollination process remains largely unclear. We use Huberia bradeana Bochorny & R. Goldenb. (Melastomataceae) with conspicuously elongated, twisted stamen appendages to investigate their functional role in the pollination process. We studied the effect of stamen appendages on pollinator behaviour and reproductive success by comparing manipulated flowers (appendages removed) with unmanipulated flowers. To assess bee pollinator behaviour, we measured three properties of buzzes (vibrations) produced by bees on Huberia flowers: frequency, duration and number of buzzes per flower visit. We measured male and female reproductive success by monitoring pollen release and deposition after single bee visits. Finally, we used artificial vibrations and laser vibrometry to assess how flower vibrational properties change with the removal of stamen appendages. Our results show that the absence of staminal appendages does not modify bee buzzing behaviour. Pollen release was higher in unmanipulated flowers, but stigmatic pollen loads differ only marginally between the two treatments. We also detected lower vibration amplitudes in intact flowers as compared to manipulated flowers in artificial vibration experiments. The presence of connective appendages are crucial in transmitting vibrations and assuring optimal pollen release. Therefore, we propose that the high diversity of colours, shapes and sizes of connective appendages in buzz-pollinated flowers may have evolved by selection through male fitness.


Subject(s)
Melastomataceae , Pollination , Animals , Bees , Flowers , Pollen , Reproduction
10.
BJOG ; 126(6): 737-743, 2019 May.
Article in English | MEDLINE | ID: mdl-30554474

ABSTRACT

OBJECTIVE: To describe the association of maternal anaemia with maternal, fetal, and neonatal outcomes. DESIGN: Prospective cohort study. SETTING: Rural India and Pakistan. POPULATION: Pregnant women residing in the study catchment area. METHODS: We performed an analysis of a prospective pregnancy registry in which haemoglobin is commonly obtained as well as maternal, fetal, and neonatal outcomes for 42 days post-delivery. Women 40 years or older who delivered before 20 weeks or had a haemoglobin level of <3.0 g/dl were excluded. Our primary exposure was maternal anaemia, which was categorised in keeping with World Health Organization criteria based on a normal (≥11 g/dl), mild (>10-10.9 g/dl), moderate (7-9.9 g/dl) or severe (<7 g/dl). haemoglobin level. The primary maternal outcome was maternal death, the primary fetal outcome was stillbirth, and the primary neonatal outcome was neonatal mortality <28 days. RESULTS: A total of 92 247 deliveries and 93 107 infants were included, of which 87.8% were born to mothers who were anaemic (mild 37.9%, moderate 49.1%, and severe 0.7%). Maternal mortality (number per 100 000) was not associated with anaemia: normal 124, mild 106, moderate 135, and severe 325 (P = 0.64). Fetal and neonatal mortality was associated with severe anaemia: stillbirth rate (n/1000)-normal 27.7, mild 25.8, moderate 30.1, and severe 90.9; P < 0.0001; 28-day neonatal mortality (n/1000)-normal 24.7, mild 22.9, moderate 28.1, and severe 72.6 (P < 0.0001). Severe maternal anaemia was also associated with low birthweight (<2500 and <1500 g), preterm birth, and postpartum haemorrhage. CONCLUSION: Severe maternal anaemia is associated with higher risks of poor maternal, fetal, and neonatal outcomes but other degrees of anaemia are not. Interventions directed at preventing severe anaemia in pregnant women should be considered. TWEETABLE ABSTRACT: Severe maternal anaemia is associated with adverse fetal and neonatal outcomes in low/middle-income countries.


Subject(s)
Anemia , Postpartum Hemorrhage , Pregnancy Complications, Hematologic , Premature Birth , Prenatal Care , Adult , Anemia/blood , Anemia/complications , Anemia/diagnosis , Anemia/epidemiology , Cohort Studies , Female , Humans , India/epidemiology , Infant , Infant Mortality , Infant, Newborn , Maternal Mortality , Pakistan/epidemiology , Postpartum Hemorrhage/diagnosis , Postpartum Hemorrhage/epidemiology , Pregnancy , Pregnancy Complications, Hematologic/blood , Pregnancy Complications, Hematologic/diagnosis , Pregnancy Complications, Hematologic/epidemiology , Pregnancy Outcome/epidemiology , Premature Birth/epidemiology , Premature Birth/prevention & control , Prenatal Care/methods , Prenatal Care/statistics & numerical data , Prospective Studies , Stillbirth
11.
BJOG ; 125(12): 1591-1599, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29782696

ABSTRACT

OBJECTIVE: Ultrasound is widely regarded as an important adjunct to antenatal care (ANC) to guide practice and reduce perinatal mortality. We assessed the impact of ANC ultrasound use at health centres in resource-limited countries. DESIGN: Cluster randomised trial. SETTING: Clusters within five countries (Democratic Republic of Congo, Guatemala, Kenya, Pakistan, and Zambia) METHODS: Clusters were randomised to standard ANC or standard care plus two ultrasounds and referral for complications. The study trained providers in intervention clusters to perform basic obstetric ultrasounds. MAIN OUTCOME MEASURES: The primary outcome was a composite of maternal mortality, maternal near-miss mortality, stillbirth, and neonatal mortality. RESULTS: During the 24-month trial, 28 intervention and 28 control clusters had 24 263 and 23 160 births, respectively; 78% in the intervention clusters received at least one study ultrasound; 60% received two. The prevalence of conditions noted including twins, placenta previa, and abnormal lie was within expected ranges. 9% were referred for an ultrasound-diagnosed condition, and 71% attended the referral. The ANC (RR 1.0 95% CI 1.00, 1.01) and hospital delivery rates for complicated pregnancies (RR 1.03 95% CI 0.89, 1.20) did not differ between intervention and control clusters nor did the composite outcome (RR 1.09 95% CI 0.97, 1.23) or its individual components. CONCLUSIONS: Despite availability of ultrasound at ANC in the intervention clusters, neither ANC nor hospital delivery for complicated pregnancies increased. The composite outcome and the individual components were not reduced. TWEETABLE ABSTRACT: Antenatal care ultrasound did not improve a composite outcome that included maternal, fetal, and neonatal mortality.


Subject(s)
Maternal-Child Health Services , Medically Underserved Area , Perinatal Care , Pregnancy Complications/diagnostic imaging , Ultrasonography, Prenatal , Adolescent , Adult , Cluster Analysis , Developing Countries , Female , Humans , Infant , Infant Mortality , Infant, Newborn , Male , Maternal Mortality , Pregnancy , Pregnancy Complications/mortality , Young Adult
15.
BJOG ; 125(2): 119-129, 2018 Jan.
Article in English | MEDLINE | ID: mdl-27704677

ABSTRACT

OBJECTIVE: Stillbirths are among the most common adverse pregnancy outcomes, with 98% occurring in low-income countries. More than one-third occur in sub-Saharan Africa (SSA). However, the medical conditions causing stillbirths and interventions to reduce stillbirths from these conditions are not well documented. We estimated the reductions in stillbirths possible with combinations of interventions. DESIGN: We developed a computerised model to estimate the impact of various interventions on stillbirths caused by the most common conditions. The model considered the location of obstetric care (home, clinic or hospital) and each intervention's efficacy, penetration and utilisation. Maternal transfers were also considered. SETTING AND POPULATION: Pregnancies in SSA in 2012. METHODS: For each condition, we created a series of scenarios involving different combinations of interventions and modelled their impact on stillbirth rates. MAIN OUTCOME MEASURES: Stillbirths associated with various maternal and fetal conditions and the percentage reduction with various interventions. RESULTS: Eight to ten maternal and fetal conditions were responsible for most stillbirths, but none for more than 15%. The most common conditions causing stillbirths in SSA include obstructed labour and uterine rupture, fetal distress and umbilical cord complications, fetal growth restriction, pre-eclampsia/eclampsia, and placental abruption/placenta praevia. Syphilis and malaria contribute smaller numbers. Reducing stillbirths requires appropriate diagnosis and management of each condition, usually including hospital care for monitoring and delivery, often by caesarean section. Maternal syphilis and malaria were the only conditions for which outpatient management alone reduced stillbirth. CONCLUSIONS: Most stillbirths in low-income countries occur at term and during labour and therefore are preventable by appropriate obstetric care. Management focused on the maternal and fetal conditions that cause stillbirths is necessary to achieve stillbirth rates approaching those found in high-income countries. TWEETABLE ABSTRACT: Reducing stillbirth incidence requires appropriate management of each causative condition and often caesarean delivery.


Subject(s)
Maternal Health Services , Models, Theoretical , Outcome Assessment, Health Care , Prenatal Care , Stillbirth/epidemiology , Africa South of the Sahara/epidemiology , Female , Humans , Obstetric Labor Complications/prevention & control , Pregnancy , Pregnancy Complications/prevention & control , Pregnancy Outcome
16.
BJOG ; 125(2): 225, 2018 01.
Article in English | MEDLINE | ID: mdl-29193728
18.
BJOG ; 125(9): 1137-1143, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29094456

ABSTRACT

OBJECTIVE: To describe the causes of maternal death in a population-based cohort in six low- and middle-income countries using a standardised, hierarchical, algorithmic cause of death (COD) methodology. DESIGN: A population-based, prospective observational study. SETTING: Seven sites in six low- to middle-income countries including the Democratic Republic of the Congo (DRC), Guatemala, India (two sites), Kenya, Pakistan and Zambia. POPULATION: All deaths among pregnant women resident in the study sites from 2014 to December 2016. METHODS: For women who died, we used a standardised questionnaire to collect clinical data regarding maternal conditions present during pregnancy and delivery. These data were analysed using a computer-based algorithm to assign cause of maternal death based on the International Classification of Disease-Maternal Mortality system (trauma, termination of pregnancy-related, eclampsia, haemorrhage, pregnancy-related infection and medical conditions). We also compared the COD results to healthcare-provider-assigned maternal COD. MAIN OUTCOME MEASURES: Assigned causes of maternal mortality. RESULTS: Among 158 205 women, there were 221 maternal deaths. The most common algorithm-assigned maternal COD were obstetric haemorrhage (38.6%), pregnancy-related infection (26.4%) and pre-eclampsia/eclampsia (18.2%). Agreement between algorithm-assigned COD and COD assigned by healthcare providers ranged from 75% for haemorrhage to 25% for medical causes coincident to pregnancy. CONCLUSIONS: The major maternal COD in the Global Network sites were haemorrhage, pregnancy-related infection and pre-eclampsia/eclampsia. This system could allow public health programmes in low- and middle-income countries to generate transparent and comparable data for maternal COD across time or regions. TWEETABLE ABSTRACT: An algorithmic system for determining maternal cause of death in low-resource settings is described.


Subject(s)
Cause of Death , Global Health/statistics & numerical data , Maternal Death/classification , Pregnancy Complications/mortality , Black People/statistics & numerical data , Democratic Republic of the Congo/epidemiology , Developing Countries , Female , Guatemala/epidemiology , Humans , Income , India/epidemiology , Kenya/epidemiology , Maternal Death/etiology , Maternal Mortality , Pakistan/epidemiology , Pregnancy , Prospective Studies , Registries , White People/statistics & numerical data , Zambia/epidemiology
19.
BJOG ; 125(2): 131-138, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28139875

ABSTRACT

OBJECTIVE: We sought to classify causes of stillbirth for six low-middle-income countries using a prospectively defined algorithm. DESIGN: Prospective, observational study. SETTING: Communities in India, Pakistan, Guatemala, Democratic Republic of Congo, Zambia and Kenya. POPULATION: Pregnant women residing in defined study regions. METHODS: Basic data regarding conditions present during pregnancy and delivery were collected. Using these data, a computer-based hierarchal algorithm assigned cause of stillbirth. Causes included birth trauma, congenital anomaly, infection, asphyxia, and preterm birth, based on existing cause of death classifications and included contributing maternal conditions. MAIN OUTCOME MEASURES: Primary cause of stillbirth. RESULTS: Of 109 911 women who were enrolled and delivered (99% of those screened in pregnancy), 2847 had a stillbirth (a rate of 27.2 per 1000 births). Asphyxia was the cause of 46.6% of the stillbirths, followed by infection (20.8%), congenital anomalies (8.4%) and prematurity (6.6%). Among those caused by asphyxia, 38% had prolonged or obstructed labour, 19% antepartum haemorrhage and 18% pre-eclampsia/eclampsia. About two-thirds (67.4%) of the stillbirths did not have signs of maceration. CONCLUSIONS: Our algorithm determined cause of stillbirth from basic data obtained from lay-health providers. The major cause of stillbirth was fetal asphyxia associated with prolonged or obstructed labour, pre-eclampsia and antepartum haemorrhage. In the African sites, infection also was an important contributor to stillbirth. Using this algorithm, we documented cause of stillbirth and its trends to inform public health programs, using consistency, transparency, and comparability across time or regions with minimal burden on the healthcare system. TWEETABLE ABSTRACT: Major causes of stillbirth are asphyxia, pre-eclampsia and haemorrhage. Infections are important in Africa.


Subject(s)
Algorithms , Registries , Stillbirth/epidemiology , Africa/epidemiology , Asia/epidemiology , Developing Countries , Female , Global Health , Guatemala/epidemiology , Humans , Maternal-Child Health Services , Pregnancy , Pregnancy Complications/epidemiology , Prospective Studies
20.
Plant Biol (Stuttg) ; 19(5): 806-817, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28627760

ABSTRACT

Flowering and fruiting are key events in the life history of plants, and both are critical to their reproductive success. Besides the role of evolutionary history, plant reproductive phenology is regulated by abiotic factors and shaped by biotic interactions with pollinators and seed dispersers. In Melastomataceae, a dominant Neotropical family, the reproductive systems vary from allogamous with biotic pollination to apomictic, and seed dispersal varies from dry (self-dispersed) to fleshy (animal-dispersed) fruits. Such variety in reproductive strategies is likely to affect flowering and fruiting phenologies. In this study, we described the reproductive phenology of 81 Melastomataceae species occurring in two biodiversity hotspots: the Atlantic rain forest and the campo rupestre. We aim to disentangle the role of abiotic and biotic factors defining flowering and fruiting times of Melastomataceae species, considering the contrasting breeding and seed dispersal systems, and their evolutionary history. In both vegetation types, pollinator-dependent species had higher flowering seasonality than pollinator-independent ones. Flowering patterns presented phylogenetic signal regardless of vegetation type. Fruiting of fleshy-fruited species was seasonal in campo rupestre but not in Atlantic rain forest; the fruiting of dry-fruited species was also not seasonal in both vegetation types. Fruiting showed a low phylogenetic signal, probably because the influence of environment and dispersal agents on fruiting time is stronger than the phylogenetic affinity. Considering these ecophylogenetic patterns, our results indicate that flowering may be shaped by the different reproductive strategies of Melastomataceae lineages, while fruiting patterns may be governed mainly by the seed dispersal strategy and flowering time, with less phylogenetic influence.


Subject(s)
Melastomataceae/physiology , Reproduction/physiology , Animals , Flowers/physiology , Fruit/physiology , Phylogeny , Pollination/physiology
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