Ovulation rate in many mammalian species is controlled to regulate the numbers of offspring and maximise reproductive success. Pathways that regulate ovulation rate still respond to genetic and environmental factors and show considerable variation within and between species. Genetic segregation, positional cloning, and association studies have discovered numerous mutations and genetic risk factors that contribute to this variation. Notable among the discoveries has been the role of mutations in bone morphogenetic protein 15 (BMP15 ), growth differentiation factor 9 (GDF9 ) and bone morphogenetic protein receptor type 1B (BMPR1B ) from the intra-ovarian signalling pathway contributing to the evidence that signalling from the oocyte is the key driver in follicle regulation rather than circulating gonadotrophin concentrations. Multiple variants in different domains of BMP15 and GDF9 result in partial or complete loss of function of the proteins providing insights into their functional roles and differential regulation contributing to species differences in ovulation rate. Early success encouraged many more studies in prolific strains of sheep, cattle and goats providing a valuable catalogue of genetic variants of large effect increasing ovulation rate and litter size. More recently, genetic association studies are beginning to identify genetic risk factors with smaller effects. Most genes implicated are from pathways with defined roles in regulation of the ovarian function. However, some genomic regions suggest regulation by novel genes. Continuing genetic and related functional studies will add further to our understanding of the detailed regulation of ovulation rate and litter size with implications for health and animal production systems.

The relationship between clinical outcomes and various factors influencing pregnancy was analyzed to provide reference data for patients and clinicians when selecting embryo transfer protocols. This was a retrospective study of 1309 transfer cycles between June 1, 2018, and May 1, 2023, in the Reproductive Medicine Center. Univariate analysis was performed on various factors that may have affected pregnancy outcomes, and further regression analysis was performed on those factors found by univariate analysis to correlate positively with clinical pregnancy outcomes. Finally, the embryo transfer schemes were compared based on the analysis results. The results showed that the stage of embryonic development significantly affected pregnancy outcomes after transplantation (P < .01, 95% confidence interval: 2.554 [1.958-3.332]). There was no significant difference in the pregnancy rate between 1 high-quality blastocyst transfer and 2 cleavage-stage embryos or blastocyst transfer (64.22% vs 70.11%, P = .439); however, the rate of multiple pregnancies after 1 high-quality blastocyst transfer was close to the rate of natural conception. These data show that the transfer of single high-quality blastocysts can significantly reduce the multiple pregnancy rate while ensuring an ideal pregnancy rate, which can be used as a reference for planning the first transplantation in patients with good prognoses.

UNASSIGNED: preterm births continue to be the main cause of infant and child mortality as well as sensory-motor disabilities and neurodevelopmental difficulties worldwide. The rate of preterm births has been rising, in particular in Algeria. The purpose of this study is to determine the frequency of preterm births in the Oran Wilaya and to identify risk factors.
UNASSIGNED: we used data from a multicentre cross-sectional study carried out in all Public Maternity Hospitals in the Oran Wilaya (13). The study included parturient women who had given birth to a live and/or stillborn child (with birthweights ≥500 g), whose gestational age was greater than or equal to 24-36 weeks of amenorrhoea. Mothers´ demographic, medical and socio-behavioural factors were recorded. Logistic regression was used to study predictors of prematurity.
UNASSIGNED: preterm birth rate was 9.9% (45/452). The average age of patients was 30.4±6 years; multiple pregnancies accounted for 2.2% of births. Factors related to prematurity were the risk of premature labour (aOR=4.68; 95% CI: 2.27-9.64), the lack of clinical monitoring of pregnancy (OR=2.83; CI 95%: 1.83-6.05) and gestational hypertension (aOR = 3.69, 95% CI: 1.83-8.8).
UNASSIGNED: the rate of preterm births is in line with the rate observed in neighbouring countries. The study identified predictive factors, some of which are already targeted by the national perinatal program. However, it is essential to continue to lead efforts to improve the monitoring and management of pregnancies and premature births at all levels of care.

BACKGROUND: The experiences and challenges associated with breastfeeding multiple births can be considerably more complex than those of singletons. Multiple births refer to the delivery of more than one offspring in a single birth event. Emphasizing the needs and experiences of mothers with multiple births during breastfeeding can enable healthcare providers to design targeted interventions that enhance breastfeeding rates. However, existing breastfeeding and health education resources and practices do not fully meet the needs of women who breastfeed multiples. This review aimed to review and synthesize qualitative studies on the breastfeeding experiences of women with multiple births.
METHODS: A systematic search was conducted in 10 electronic databases for papers published from the inception of the database to March 2024. The Joanna Briggs Institute Critical Appraisal Checklist for Qualitative Research was utilized to evaluate the methodological quality of the studies included. The thematic synthesis method of Thomas and Harden was employed to integrate and analyze the included literature to derive new categories and conclusions.
RESULTS: Eight studies met the inclusion criteria and quality assessment criteria for this study. Through the integration of their results, four themes were identified: the choice and willingness to breastfeed multiple births; the challenges of breastfeeding multiple births; stage management and individualised adaptation of breastfeeding; and the experience of support.
CONCLUSIONS: Throughout the feeding process from pregnancy to the postpartum period, mothers with multiple births often have predominantly negative experiences with breastfeeding. Consequently, hospitals should create a multidisciplinary follow-up team comprising obstetrics, neonatology, psychology, and community services to offer specialized and personalized support to these women at various stages.
BACKGROUND: [ https://www.crd.york.ac.uk/PROSPERO/ ], identifier [PROSPERO 2024 CRD42024520348].

BACKGROUND: Lower gestational age negatively affects the neurodevelopmental outcomes of infants. Early motor repertoire is a reliable way to predict neurodevelopmental outcomes. This study aimed to determine the correlation between gestational age and early motor repertoire in infants and also the roles of multiple pregnancies, gender, cranial utrasonography (USG) results, and birth weight in this relationship.
METHODS: This study included 139 infants, who were video recorded 9-17 weeks post-term. The recordings were evaluated using the Motor Optimality Score-Revised (MOS-R). Structural equation modeling tool was used for the path analysis of the models.
RESULTS: There was a weak positive correlation between gestational age and the MOS-R. In the relationship between gestational age and the MOS-R, multiple pregnancies, gender, and USG outcomes had a moderating effect. While abnormal USG, male gender, and singleton pregnancy increased this correlation to a moderate level, normal USG reduced the strength of the correlation. Female and twin pregnancies were non-significant in the model. Birth weight had a full mediating effect on the relationship between gestational age and the MOS-R.
CONCLUSIONS: Infants with younger gestational age or lower birth weight, male infants, and infants with problems on cranial USG may have poorer early motor repertoire.

Twin pregnancies compromise the health and well-being of dairy cattle. A recent genomic prediction model for twin pregnancies has been developed based on twin calving or abortion. However, the incidence of double ovulation is significantly higher than that of twin births. This study aimed to evaluate whether genomic prediction values for twin pregnancies are associated with the incidence of double ovulation in primiparous dairy cows. Factors influencing the double ovulation rate were analysed using binary logistic regression on 676 cows: 475 (70.3%) inseminated at spontaneous estrus and 201 following one of two different estrus synchronization protocols for fixed-time artificial insemination (FTAI). The odds ratio for double ovulations was 0.92 (p = .002) per unit increase in prediction value and 2 (p = .01) for cows subjected to an FTAI protocol. Our findings suggest that genomic prediction values for twin pregnancies can effectively identify the risk of double ovulation at the herd level.

OBJECTIVE: To evaluate the relative impact of different strategies of medically assisted reproduction (MAR), i.e. first line treatment (ovarian stimulation with or without intrauterine insemination) and in vitro fertilization (IVF) procedures (conventional IVF or intracytoplasmic sperm injection), on the risk of multiple births.
METHODS: We utilized the health care utilization databases of the Lombardy region to identify births resulting from MAR between 2007 and 2022. We gathered data on the total number of multiple births and calculated the prevalence rate by dividing the number of multiples by the total number of births. To examine the temporal trend in the proportion of multiple births after MAR over time, a linear regression model was employed separately for different types of techniques and in strata of maternal age.
RESULTS: A total of 30,900 births after MAR were included; 4485 (14.5 %) first line treatments and 26,415 (85.5 %) IVF techniques. Overall, 4823 (15.6 %) multiple births were identified. The frequency of multiple births over the study period decreased from 22.0 % in 2007 to 8.7 % in 2022 (p < 0.01). Multiple births from first line treatments were stable ranging from 13.5 % in 2007-2008 to 12.0 % in 2021-2022 (p = 0.29). Multiple births from IVF procedures decreased from 23.8 % in 2007-2008 to 8.4 % in 2021-2022 (p < 0.01). Stratifying for maternal age (i.e. < 35 and ≥ 35 years), the trends remained consistent.
CONCLUSIONS: The reduction in multiple births has been influenced by changes in IVF strategy and procedures. The decline has been gradual but steady since 2009, when a law restricting embryo freezing was repealed in Italy. In contrast, the proportion of multiple births resulting from first line treatments has remained constant over time. Despite declining, multiple births from MAR remained about one order of magnitude higher than those from spontaneous pregnancies.

OBJECTIVE: This paper aims to analyze the factors that can influence the method of childbirth in women with multiple pregnancies.
METHODS: Retrospective analysis of selected parameters in women with multiple pregnancies who gave birth at the 2nd Clinic of Gynecology and Obstetrics of the Faculty of Medicine (FM), Comenius University (CU) and University Hospital (UH) Bratislava in the years 2010-2022.
RESULTS: Between 2010 and 2022, at the 2nd Clinic of Gynecology and Obstetrics of the FM CU and UH in Bratislava, 1.13% of births were multiple pregnancies. After statistical data processing, primiparity appeared statistically significant as a risk of acute caesarean section (C-section); multiparous women had a higher probability to give birth vaginally. Since 2017, the clinic has had a decreasing trend in the number of caesarean sections. Women with an acute caesarean section, in turn had on average a lower pH of both fetuses compared to vaginal delivery. However, the incidence of asphyxia in fetuses was not statistically significantly different. We found no risk factor increasing the likelihood of acute caesarean section for fetus B in twins.
CONCLUSIONS: Multiple pregnancy has a higher morbidity not only for the woman but also for the fetuses. The incidence of multiple pregnancies is influenced by assisted reproduction. Delivery method depends on various factors such as chorionicity, fetal presentation, and history of a previous caesarean section.

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Twin pregnancy in cattle is undesirable for a number of reasons, including a higher abortion risk compared to pregnancies with a single foetus. Yet, the abortion risk is significantly influenced by the intrauterine location of the foetuses, that is, the abortion risk is several times higher if they are implanted in the same uterine horn (unilateral twin pregnancy) than if they are implanted with one foetus in each uterine horn (bilateral twin pregnancy). The reason for the higher abortion risk in unilateral twin pregnancies is unknown, but it may be related to malnutrition of the outermost foetus due to a limited placental capacity, as is the case for equine twin foetuses. A slaughterhouse study was performed and the foetuses of cattle pregnant with twins were measured. We identified 65 cases of twin pregnancies, of which 35 were unilateral twin pregnancies and 30 were bilateral twin pregnancies. There was no significant difference between the outermost and the more centrally located foetus in unilateral twin pregnancies in terms of body weight and length of the metacarpal diaphysis. Growth retardation of the outermost foetus could therefore not be confirmed as the cause of the higher abortion risk in unilateral bovine twin pregnancies. Four cases of pre-slaughter foetal mortality were identified. In three of these cases, both twins were dead, of equal size and at a comparable level of degradation. In the fourth case, with approximately 40-day-old twin foetuses of equal size, only one of the foetuses showed signs of pre-slaughter death.