On the road: Anthropogenic factors drive the invasion risk of a wild solitary bee species.

Complex biotic networks of invaders and their new environments pose immense challenges for researchers aiming to predict current and future occupancy of introduced species. This might be especially true for invasive bees, as they enter novel trophic interactions. Little attention has been paid to solitary, invasive wild bees, despite their increasing recognition as a potential global threat to biodiversity. Here, we present the first comprehensive species distribution modelling approach targeting the invasive bee Megachile sculpturalis, which is currently undergoing parallel range expansion in North America and Europe. While the species has largely colonised the most highly suitable areas of North America over the past decades, its invasion of Europe seems to be in its early stages. We showed that its current distribution is largely explained by anthropogenic factors, suggesting that its spread is facilitated by road and maritime traffic, largely beyond its intrinsic dispersal ability. Our results suggest that M. sculpturalis is likely to be negatively affected by future climate change in North America, while in Europe the potential suitable areas at-risk of invasion remain equally large. Based on our study, we emphasise the role of expert knowledge for evaluation of ecologically meaningful variables implemented and interpreted for species distribution modelling. We strongly recommend that the monitoring of this and other invasive pollinator species should be prioritised in areas identified as at-risk, alongside development of effective management strategies.

Unprecedented Density and Persistence of Feral Honey Bees in Urban Environments of a Large SE-European City (Belgrade, Serbia).

It is assumed that wild honey bees have become largely extinct across Europe since the 1980s, following the introduction of exotic ectoparasitic mite (Varroa) and the associated spillover of various pathogens. However, several recent studies reported on unmanaged colonies that survived the Varroa mite infestation. Herewith, we present another case of unmanaged, free-living population of honey bees in SE Europe, a rare case of feral bees inhabiting a large and highly populated urban area: Belgrade, the capital of Serbia. We compiled a massive data-set derived from opportunistic citizen science (>1300 records) during the 2011-2017 period and investigated whether these honey bee colonies and the high incidence of swarms could be a result of a stable, self-sustaining feral population (i.e., not of regular inflow of swarms escaping from local managed apiaries), and discussed various explanations for its existence. We also present the possibilities and challenges associated with the detection and effective monitoring of feral/wild honey bees in urban settings, and the role of citizen science in such endeavors. Our results will underpin ongoing initiatives to better understand and support naturally selected resistance mechanisms against the Varroa mite, which should contribute to alleviating current threats and risks to global apiculture and food production security.

Northwestward range expansion of the bumblebee Bombus haematurus into Central Europe is associated with warmer winters and niche conservatism.

Species range expansions are crucial for understanding niche formation and the interaction with the environment. Here, we studied the bumblebee Bombus haematurus Kriechbaumer, 1870, a species historically distributed from northern Serbia through northern Iran which has very recently started expanding northwestward into Central Europe without human-mediated dispersal (i.e., it is a natural spread). After updating the global distribution of this species, we investigated if niche shifts took place during this range expansion between newly colonized and historical areas. In addition, we have explored which climatic factors may have favored the natural range expansion of the species. Our results indicated that Bombus haematurus has colonized large territories in 7 European countries outside the historical area in the period from the 1980s to 2018, a natural expansion over an area that equals 20% of the historical distribution. In addition, this bumblebee performs generalism in flower visitation and it occurs in different habitats, although a preference for forested areas clearly emerges. The land-use associated with the species in the colonized areas is similar to the historical distribution, indicating that no major niche shifts occurred during the spread. Furthermore, in recently colonized localities, the range expansion was associated with warming temperatures during the winter and also during both queen overwintering and emergence phases. These findings document a case of natural range expansion due to environmental change rather than due to niche shifts, and specifically they suggest that warmer winters could be linked to the process of natural colonization of new areas.

A global synthesis reveals biodiversity-mediated benefits for crop production.

Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.

Crop pests and predators exhibit inconsistent responses to surrounding landscape composition.

The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win-win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.

Bee (Hymenoptera: Apoidea) and hoverfly (Diptera: Syrphidae) pollinators in Pannonian habitats of Serbia, with a description of a new Eumerus Meigen species (Syrphidae).

The diversity of bee (Hymenoptera: Apoidea) and hoverfly (Diptera: Syrphidae) pollinators from ten localities in Vojvodina, Serbia was surveyed. Among different types of Pannonian habitat (grasslands, heathland and scrub, woodland and forest habitats) all localities were categorised as forest and steppe. They were in protected areas, mostly undisturbed by human activity. Censuses of pollinators took place from 30 March to 10 October, 2014. We recorded 218 pollinator species; 135 bee species (42 Halictidae; 32 Apidae; 29 Andrenidae; 24 Megachilidae; 7 Colletidae; 1 Melittidae) and 83 species of hoverflies. We describe a new species of hoverfly, Eumerus pannonicus sp. nov., and compare it to other similar species. Based on our study, the Special Nature Reserve of Pasnjaci Velike Droplje is critical for the conservation of this new Eumerus-being only found at this locality-and other species such as Chrysotoxum lineare (Zetterstedt), which is rare in Europe and protected under Serbian legislation. The highest numbers of bee species were recorded in the Deliblato and Subotica sand areas (40 and 32, respectively), while Fruska Gora Mountain and the Vrsac Mountains harboured the highest number of hoverfly species.

Clients' Perception of Outcome of Team-Based Prenatal and Reproductive Genetic Counseling in Serbian Service Using the Perceived Personal Control (PPC) Questionnaire.

This is the first study in Serbia and the region of South-East Europe dedicated to clients' perception of outcome and efficiency of prenatal and reproductive genetic counseling. The primary aim of this study was to assess overall value and success of genetic counseling in prenatal and reproductive care with regard to perceived personal control of clients, reflecting also in a part patient comprehension, knowledge retention, and empowerment in decision-making. The standardized Perceived Personal Control questionnaire (PPC) was used for the assessment of 239 female participants. First, we performed a complete validation of the psychometric characteristics of the Serbian-language version of the PPC questionnaire. The validation of the questionnaire permits other researchers from Serbian-speaking regions of South-East Europe to use this standard instrument to assess the effectiveness of prenatal genetic counseling in their communities and analyze advantages and disadvantages of their counseling models. We also measured social and demographic characteristics of participants. Further, we analyzed effects of our team-based prenatal and reproductive genetic counseling model through (a) calculation of PPC scores at three different stages (before initial, after initial, and before second counseling session), and (b) by assessing participants' responses by indication for referral (advanced maternal age, abnormal biochemical screening, family history of hereditary disorders, maternal exposure to drugs, exposure to radiation, exposure to infective agents, infertility or recurrent abortions, and miscellaneous). The results indicate that participants' knowledge after initial counseling increased significantly and after that remained stable and sustainable. A satisfactory level of confidence among participants had been achieved, in that many felt an increased sense of control over their situation and emotional response to it. Indirectly, these results indicate the success of a team-based prenatal genetic counseling model, which has not been assessed in the literature to date.

Fauna Europaea: Hymenoptera - Apocrita (excl. Ichneumonoidea).

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Hymenoptera is one of the four largest orders of insects, with about 130,000 described species. In the Fauna Europaea database, 'Hymenoptera - Apocrita (excluding Ichneumonoidea)' comprises 13 superfamilies, 52 families, 91 subfamilies, 38 tribes and 13,211 species. The paper includes a complete list of taxa dealt with, the number of species in each and the name of the specialist responsible for data acquisition. As a general conclusion about the European fauna of Hymenoptera, the best known countries in terms of recorded species are those from northwestern Europe, with the least known fauna probably in the more eastern and southeastern parts of Europe.

Prospective study of perinatal outcome in pregnancies with primary antiphospholipid syndrome.

BACKGROUND/AIM: Pregnancies complicated with antiphospholipd syndrome are associated with the increased perinatal mortality and morbidity. The aim of this study was to assess perinatal outcome in pregnancies with primary antiphospholipd syndrome. METHODS: This prospective study evaluated perinatal outcome in 25 pregnant women with antiphospholipid syndrome. After establishing vital pregnancy all the patients were treated with low-molecular-weight heparin and aspirin. The perinatal outcome was measured by rates of miscarriages, preterm deliveries, live births and neonatal complications. RESULTS: Of the 25 pregnancies, 20 (80%) resulted in live birth, 3 (12%) in spontaneous abortion and 2 (8%) were stillbirths. The mean gestational age at delivery was 37.2 +/- 1.0 weeks, mean neonatal birth weight was 2,930.4 +/- 428.0 g. Prematurity occurs in 4 (20%) live births, and there were 4 (20%) intrauterine growth restriction with mean birth weight 2,060 +/- 210.6 g. Neonatal complications were present in 6 (3%) newborns. Adverse perinatal outcome was significantly associated with anticardiolipin IgG antibodies (p < 0.01) and development of hypertension during pregnancy (p < 0.01). CONCLUSION: Despite a high incidence of adverse perinatal outcomes in pregnancies with primary antiphospholipid syndrome, early treatment with aspirin and low-molecular-weight heparin, combined with meticulous fetomaternal monitoring could be associated with a relatively high probability of favorable perinatal outcome.

Review of the Gasteruptiidae (Hymenoptera: Evanioidea) from the territory of the former Yugoslavia, with three newly reported species.

The results of more than 120 years of investigation of the fauna of Gasteruptiidae for the territory of former Yugoslavia (including Bosnia and Herzegovina, Croatia, FYR of Macedonia, Montenegro, Serbia and Slovenia) are summarized. Results from recently collected material and from unidentified specimens in collections are combined with those of published records. The total number of valid species of the genus Gasteruption Latreille for the area of former Yugoslavia is 22, which is more than in any country represented in Fauna Europaea database. One species is firstly recorded for the mainland Europe (G. syriacum Szépligeti), two more species are newly recorded for the investigated area and there are 23 first country-records for the involved countries (based on 17 species).

Plasma kisspeptin levels in pregnancies with diabetes and hypertensive disease as a potential marker of placental dysfunction and adverse perinatal outcome.

BACKGROUND: The aim of this study was to prospectively evaluate plasma kisspeptin levels in 129 singleton pregnancies with diabetes [pregestational insulin-dependent diabetes mellitus (type 1) and gestational diabetes (GD)] and hypertensive disease [chronic hypertension (CH), gestational hypertension, and preeclampsia (PE)] as a potential marker of placental dysfunction and adverse perinatal outcome. STUDY DESIGN: Kisspeptin levels were evaluated in the first, second, and third trimesters in patients with type 1 diabetes (16 patients), H (22), and healthy control (25) and in the second and third trimesters in patients with GD (20), gestational hypertension (18), and PE (28). Maternal kisspeptin levels were correlated with pregnancy outcome, parameters of fetoplacental circulation, ultrasound-detected abnormalities of placental morphology, and placental weight at delivery. RESULTS: In pregnancies with type 1 diabetes and H, mean kisspeptin levels were significantly lower compared with the control group (p<0.001 in the first and second trimesters and p<0.05 in the third trimester). Decreased plasma kisspeptin levels in the second and third trimesters were found in patients with GD (p<0.001 in the second and third trimesters) and PE (p<0.001 in the second trimester and p<0.05 in the third trimester). In patients with PE and placental dysfunction, low kisspeptin levels in the third trimester were associated with adverse perinatal outcome. CONCLUSIONS: Our study demonstrates reduced kisspeptin levels in pregnancies with diabetes, H, PE, and placental dysfunction. In patients with PE and placental dysfunction, decreased kisspeptin levels were associated with adverse perinatal outcome. Larger studies are needed to investigate the role of kisspeptin as a potential marker of placental dysfunction and adverse perinatal outcome.

Parasitoids (Hymenoptera: Braconidae: Aphidiinae) of northeastern Iran: aphidiine-aphid-plant associations, key and description of a new species.

Aphid parasitoids of the subfamily Aphidiinae (Hymenoptera: Braconidae) of northeastern Iran were studied in this paper. A total of 29 species are keyed and illustrated with line drawings. The aphidiines presented in this work have been reared from 42 aphid host taxa occurring on 49 plant taxa from a total of 33 sampling sites. Sixty-six aphidiine-aphid-plant associations are presented. Trioxys metacarpalis sp. nov. from Chaitaphis tenuicaudata Nevsky (Hemiptera: Aphididae) on Kochia scoparia, is described. The species diversity based on the comparative faunistic analysis is discussed.

Thiobarbituric acid reactive substances as marker of oxidative stress in pregnancies with pre-eclampsia.

Pre-eclampsia is characterized by increased lipid peroxidation and diminished antioxidant capacity. The aim of the study was to establish concentration of thiobarbituric acid reactive substances as a marker of lipid peroxidation in normal pregnancies and in pregnancies complicated with pre-eclampsia, and to estimate the possibility of using thiobarbituric acid reactive substances as a screening method for development of pre-eclampsia. The study was conducted at the Department of Obstetrics and Gynaecology, Clinical Centre of Vojvodina. The study included 57 singleton pregnancies, gestation > or = 24 weeks, of which 29 were healthy pregnancies and 28 were with pre-eclampsia, defined as systolic arterial pressure of > or = 90 mmHg, diastolic of > or = 145 mmHg, and 24h proteinuria of > or = 300 mg. Thiobarbituric acid reactive substances concentrations evaluated by malondialdehyde equivalent standards (OxiSelect TBARS Assay Kit (malondialdehyde Quantitation), Cell Biolabs' OxiSelect) showed that oxidative stress was more evident in the group with pre-eclampsia, though not statistically significant (p = 0.107). There was no correlation ofthiobarbituric acid reactive substance levels with gestation in either group. The differences between the level of thiobarbituric acid reactive substance concentrations in pre-eclampsia and healthy pregnancies indicate the possibility of using thiobarbituric acid reactive substances as a screening tool for the development of pre-eclampsia. Further studies with larger numbers of patients are needed in order to come to final conclusions.

[Primary carcinoid of the ovary].

BACKGROUND: Carcinoid tumors are distinct neuroendocrine neoplasms commonly located within the gastrointestinal tract and bronchopulmonary system. The aim of this case report was to present a patient with carcinoid tumor of the ovary as a less common form of this neoplasm. CASE REPORT: A 49 year old woman was admitted to the hospital with symptoms of diarrhea and abdominal pain and suspicion of neuroendocrine neoplasm, 4 month after bilateral salpingo-oophorectomy and total hysterectomy for ovarian tumor. Pathological diagnosis was typical for carcinoid tumor. At admission the patient had slightly eleveated levels of tumor marker CA 125 and highly elevated levels of 5- HIAA. Abdominal CT showed suspicious rest tumor in the pelvis. Relaparotomy was done and retroperitoneal fibrosis was found. Six months after the intervention the levels of 5-HIAA and CA 125 were normal, and NMR of the abdomen showed no signs of rest tumor. CONCLUSION: Carcinoid tumor of the ovary is rare form of ovarian tumors and less than 0.1% had malignant potential. Surgical therapy associated with a long-term followup was the treatment of choice. Consideration of unusual sites of carcinoid tumors facilitates appropriate diagnosis and treatment.

Regional tritrophic relationship patterns of five aphid parasitoid species (Hymenoptera: Braconidae: Aphidiinae) in agroecosystem-dominated landscapes of southeastern Europe.

A regional survey of the complex tritrophic associations (parasitoid-aphid-plant) of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) was carried out to determine and explore the patterns of those associations in various types of environments. Here, we present trophic relationship patterns of the five aphid parasitoid species in crop and noncrop habitats in southeastern Europe, and we contrast them in a regional (Mediterranean [MED] versus continental [CNT]) context. In total, 79 aphid host taxa were identified in this survey. Forty-two of these were recorded from noncrop plants only, 21 from crop plants only, and 18 were present on both types of plants. This means that approximately 74% of all the parasitoid-aphid trophic interactions that support the persistence of the five selected parasitoids are entirely (54%) or partially (20%) associated with noncrop plants. The correspondence of parasitoid-aphid combinations among habitat/region combinations is very high and specific. Our results suggest that Mediterranean and continental regions are clearly distinguished by a contrasting pattern of trophic interactions in crop habitats, whereas the noncrop habitats contribute in lesser degree to these differences. For the crop/noncrop breakdown, the number of nonspecific interactions was larger than expected in crop habitats, whereas in noncrop habitats the abundance of partially specific and specific interactions was larger. The analysis of variance for the regional and habitat distribution of mean aphid host number per parasitoid was highly significant. When both regions were analyzed separately, the parasitoid/crop design showed significant parasitoid effects as well as interactions, whereas the habitat effect was not significant for the Mediterranean region and highly so for the continental region. This highly complex pattern suggests that the mean number of parasitized aphid species is not distributed among parasitoids, regions, and habitats in a similar manner. Even with these complexities taken into account, the overall trend is that noncrop habitats support more parasitoid-aphid combinations and more so in the continental than in Mediterranean regions, although not always statistically significant. As mentioned, large number of noncrop aphid hosts, especially for Lysiphlebus fabarum (Marshall), Praon volucre (Haliday) and Aphidius colemani Viereck, can significantly enhance the population buildup for these important parasitoids around agroecosystems. These facts can be important in biological aphid pest control in the region. Although not easily quantified, the overall positive effects of larger parasitoid diversity in noncrop habitats are undoubtedly related to the distribution and structure of noncrop habitat patches in agroecosystems at a landscape scale.

[Serum inhibin B in polycystic ovary syndrome as a potential marker of ovarian dysfunction].

INTRODUCTION: Polycystic ovary syndrome (PCOS) is one of the most common causes of anovulation, infertility and hyperandrogenism, and the prevalence of this condition in women of reproductive is 5-10%. The growth of early ovarian antral follicles is arrested and dominant follicle selection is disturbed in this syndrome. OBJECTIVE: The aim of this study is to investigate whether inhibin B serum concentrations represent the extent of ovarian abnormalities in patients with PCOS. METHOD: Inhibin B serum concentrations on the third day of spontaneous menstrual cycle and other endocrine characteristics were compared between 20 patients with PCOS and 19 healthy women in the control group. RESULTS: Inhibin B concentrations were not significantly different between women with PCOS and women in the control group. In patients with PCOS there was statistically significant correlation between serum inhibin B and LH (r = 0.514; p = 0.021).There were no positive correlations between inhibin B and others endocrine parameters in patients with PCOS (FSH, E2,T, androstenedione). CONCLUSION: Inhibin B serum concentrations on the third day of spontaneous menstrual cycle in women with PCOS are not different from the concentrations in healthy women. Serum Inhibin B levels in patients with PCOS are only slightly correlated with the endocrine markers of the disease so it could not represent the magnitude of ovarian dysfunction in this syndrome.

[Neonatal outcome in pregnancies complicated with pregestational diabetes mellitus].

BACKGROUND/AIM: Pregestational diabetes mellitus (PGDM) represents glucose intolerance that begins before pregnancy and is followed by the increased risk of neonatal and maternal complications. The aim of this study was to establish neonatal outcome in pregnancies with pregestational diabetes mellitus and the factors that had influence on it. METHODS: This study included 27 pregnant women with insulin-dependant PGDM hospitalized during 2004 in the Institute for Obstretics and Gynecology, Clinical Center of Serbia, Belgrade. The control group consisted of 2 292 healthy pregnant women presented to the Institute within 2004. RESULTS: Twenty-three (85%) infants of the women with PGDM had complications in comparison with 356 (15.5%) infants of the women in the control group, that was statistically significant difference (p < 0.001). Macrosomia was present in 8 (29.6%/0) and birth injuries in 6 (22.2%) infants of women with PGDM that was statistically significant difference (p < 0.001) in comparisom with the women in the control group who had 194 (8.5%) infants with macrosomia and 156 (6.8%) infants with birth injuries. The women with PGDM had 3 (11.1%) neonatal deaths and 3 (11.1%) infants were born with congenital malformations in comparison with the women in the control group without these complications. We established statisticaly significant correlation (p < 0.001) between glicoregulation before and during pregnancy in the women with PGDM and neonatal outcome. CONCLUSION: The incidence of neonatal morbidity and mortality in the women with PGDM was significantely more frequent as compared with the normal population. Achieving optimal maternal glucose levels in women with PGDM both preconceptionally and during pregnancy is associated with significant reduction of neonatal complications.

[Leptin and inhibin B as predictors of reproductive recovery in patients with anorexia nervosa during weight gain].

INTRODUCTION: Anorexia nervosa represents an eating disorder that is associated with substantial psychological, social and physiological abnormalities, involving 0.5-2% of female population. OBJECTIVE: The secretion patterns of inhibin B, as marker of gonadal activity, and leptin, as an indicator of energy balance and body composition, were analyzed in our cross-sectional study in order to asses the restoration of reproductive function in patients with anorexia nervosa (AN) during gaining of normal weight. METHOD: The study included 20 patients with low weight AN (BMI 14.3 +/- 0.3 kg/m2), 22 partially recovered AN (BMI 17.4 +/- 0.1 kg/m2), and 29 gained regular weight, out of whom 16 had no restoration of menstrual cycle (BMI 19.5 +/- 0.1 kg/m2), and 13 had at least six consecutive menstrual cycles (BMI 19.3 +/- 1.0 kg/m2). Nineteen eumenorrheic females with BMI 19.8 +/- 0.4 kg/m2 were the controls. RESULTS: Significant correlation between leptin and inhibin B (c = 0.446; p = 0.000), leptin and delta LH (c = 0.611; p < 0.001), and inhibin B and delta LH (c = 0.574; p < 0.001) was found in patients with anorexia nervosa during weight gain. Leptin (p = 0.0039), inhibin B (p = 0.0173), LH (p = 0.0323) and delta LH (p = 0.0087) were important predictors of reproductive recovery in patients with anorexia nervosa during gaining of normal weight. Among aforementioned parameters, leptin (p = 0.0057) appeared to be the most important. CONCLUSION: Leptin is the most important predictor of reproductive recovery in patients with anorexia nervosa during weight normalization. These findings suggest that decreased leptin levels may be responsible for several neuroendocrine abnormalities seen in anorexia nervosa. Thus, interventional studies involving administration of recombinant leptin are required to fully clarify the physiologic and potentially therapeutic role of leptin in anorexia nervosa.

Inhibin B: a potential marker of gonadal activity in patients with anorexia nervosa during weight recovery.

Inhibin B is a product of the gonads and a marker for ovarian follicular development. This was a cross-sectional study designed to assess awakening of the reproductive function by studying secretion pattern of inhibin B during the weight restoration in patients with anorexia nervosa (AN). Twenty patients with AN participated at low weight [body mass index (BMI) 14.3 +/- 0.3 kg/m(2))], 22 partially weight recovered AN (BMI 17.4 +/- 0.1 kg/m(2)), 16 reached goal weight but did not restore menstrual cycles (BMI 19.5 +/- 0.1 kg/m(2)), and 13 reached goal weight and had at least six consecutive menstrual cycles (BMI 19.3 +/- 1.0 kg/m(2)). Nineteen eumenorrheic females with BMI 19.8 +/- 0.4 kg/m(2) served as controls. At low weight, patients had low basal leptin, inhibin B detectable in only 15% of samples, and LH significantly lower than in controls (P < 0.01). At weight gain, basal leptin increased, median inhibin B increased (detectable in 66.7% of samples), and LH remained low, all significantly lower than in controls (P < 0.01). Weight-recovered/amenorrheic patients further increased basal leptin, inhibin B was detectable in all samples, and LH remained low, all significantly lower than in controls (P < 0.01). In weight-recovered/cycling patients, basal leptin, median inhibin B, and LH, as expected, were not different from healthy volunteers. Inhibin B values correlated significantly with leptin (P = 0.000) and BMI (P = 0.000). In summary, gonads in patients with AN who gain weight are not entirely quiescent but have a low level of activity. Inhibin B is an early marker of gonadal activity, and with weight gain, awakening of the reproductive function is gradual, whereas factors triggering the onset of menstrual cycles still remain unknown (nutritional fat intake, psychological).