The effects of commercial preparations of red raspberry leaf on the contractility of the rat's uterus in vitro

Raspberry leaf (Rubus idaeus) use in pregnancy: a prospective observational study

BACKGROUND

Raspberry leaf use during pregnancy in Australia is widespread. There has been little research exploring the potential beneficial or harmful effects of raspberry leaf on pregnancy, labour, and birth. More research is needed to appropriately inform childbearing women and maternity healthcare professionals on the effects of raspberry leaf so that women can make informed choices.

METHODS

This study aimed to determine associations between raspberry leaf use in pregnancy and augmentation of labour and other secondary outcomes. Data was derived from questionnaires which captured demographic information and herbal use in pregnancy. Clinical outcomes were accessed from the maternity services' clinical database. Data analysis was conducted in R via package 'brms' an implementation for Bayesian regression models.

RESULTS

A total of 91 completed records were obtained, 44 exposed to raspberry leaf and 47, not exposed. A smaller proportion of women in the raspberry leaf cohort had augmentation of labour, epidural anaesthesia, instrumental births, caesarean section, and postpartum haemorrhage. A larger proportion had vaginal birth and length of all phases of labour were shorter. Under these conditions the use of raspberry leaf was strongly predictive of women not having their labours medically augmented.

CONCLUSIONS

While our study demonstrated that raspberry leaf was strongly predictive of women not having their labours medically augmented, the results cannot be relied on or generalised to the wider population of pregnant women. While there were no safety concerns observed in our study, this should not be taken as evidence that raspberry leaf is safe. A randomised controlled trial is urgently needed to provide women and healthcare providers with robust evidence on which to base practice.

Raspberry Leaves and Extracts-Molecular Mechanism of Action and Its Effectiveness on Human Cervical Ripening and the Induction of Labor

The gestational period is an incredibly stressful time for a pregnant woman. Pregnant patients constantly seek effective and reliable compounds in order to achieve a healthy labor. Nowadays, increasing numbers of women use herbal preparations and supplements during pregnancy. One of the most popular and most frequently chosen herbs during pregnancy is the raspberry leaf (Rubus idaeus). Raspberry extracts are allegedly associated with a positive effect on childbirth through the induction of uterine contractions, acceleration of the cervical ripening, and shortening of childbirth. The history of the consumption of raspberry leaves throughout pregnancy is vast. This review shows the current status of the use of raspberry leaves in pregnancy, emphasizing the effect on the cervix, and the safety profile of this herb. The majority of women apply raspberry leaves during pregnancy to induce and ease labor. However, it has not been possible to determine the exact effect of using raspberry extracts on the course of childbirth and the perinatal period. Additionally, it is unclear whether this herb has only positive effects. The currently available data indicate a weak effect of raspberry leaf extracts on labor induction and, at the same time, their possible negative impact on cervical ripening.

Survey of Raspberry Leaf Tea in pregnancy

BACKGROUND

Raspberry leaf tea (RLT) is a traditional herb purported to help with many pregnancy-related outcomes including reducing the duration of labour. No experimental data exist to support these claims.

AIMS

This study aims to determine how common use and knowledge of RLT are during pregnancy. It also aims to explore whether it would be possible to recruit women for a trial of raspberry leaf in the future.

MATERIALS AND METHODS

Postnatal women were asked to fill in a survey about their use of RLT during pregnancy, and their knowledge of its purported benefits. They were asked whether they would consider being part of a randomised controlled trial of raspberry leaf in the future.

RESULTS

One hundred and twenty-one women completed the survey. Of these, 88 (73%) were aware of herbal tea use in pregnancy and 46 (38%) reported using raspberry leaf during pregnancy. Of all women surveyed, 79% indicated they would be happy to participate in a trial of RLT in pregnancy if they were asked.

CONCLUSIONS

Despite no scientific evidence of the efficacy of RLT in pregnancy, 38% of women surveyed used it during pregnancy. Further studies are required to determine whether the claims made about RLT are correct. Clinicians should base their advice on available evidence.

Effect of Rubus idaeus L. Consumption During Pregnancy on Maternal Mice and Their Offspring

The trigger for human labor is a scientific mystery. This research examined Rubus idaeus (RI), commonly referred to as red raspberry, which is widely purported to be efficacious in promoting parturition processes and favorable birth outcomes. This randomized controlled trial sought to determine the influence of RI consumption during gestation on C57BL/6N Tac mice and their offspring. The aims of this study were to (1) determine differences in the length of gestation, gestational weight gain, and litter size where RI is consumed daily at varied strengths and (2) determine differences in offspring characteristics and behavior where maternal RI consumption occurred. Once paired, mice were randomly assigned to one of three groups: placebo (n = 10) receiving plain water, RI aqueous extract fluid of 1.78 mg/mL (n = 10), or RI aqueous extract fluid of 2.66 mg/mL (n = 10). All received the same standardized diet throughout gestation. Pregnant mice were weighed with chow intake and fluid consumption determined daily. Gestation length and litter size were recorded at the time of birth. Differences in offspring characteristics were also determined and included physical characteristics (weight, physical development) and neuromotor reflexes and behaviors (locomotive abilities, geotaxis reflex, cliff avoidance reflex, and swimming development). When compared with controls, high-dose RI ingestion resulted in shorter length of gestation and smaller litter size (P ≤ .05). There was also an increase in fluid consumption and a decrease in pup weights on postnatal day 4 and 5 with RI treatment (P ≤ .05). Altogether, results suggest that RI influences parturition and fecundity processes with transplacental exposure impacting offspring characteristics.

Biophysical effects, safety and efficacy of raspberry leaf use in pregnancy: a systematic integrative review

Background

Childbearing women have been using various herbs to assist with pregnancy, labour and birth for centuries. One of the most common is raspberry leaf. The evidence base for the use of raspberry leaf is however under-developed. It is incumbent on midwives and other maternity care providers to provide women with evidence-based information so they can make informed choices. The aim of this study was to review the research literature to identify the evidence base on the biophysical effects, safety and efficacy of raspberry leaf in pregnancy.

Methods

A systematic, integrative review was undertaken. Six databases were searched to identify empirical research papers published in peer reviewed journals including in vitro, in vivo, human and animal studies. The search included the databases CINAHL, MEDLINE, Cochrane Library, Scopus and Web of Science Core Collection and AMED. Identified studies were appraised independently by two reviewers using the MMAT appraisal instrument. An integrative approach was taken to analysis.

Results

Thirteen studies were included. Five were laboratory studies using animal and human tissue, two were experiments using animals, and six were human studies. Included studies were published between 1941 and 2016. Raspberry leaf has been shown to have biophysical effects on animal and human smooth muscle including the uterus. Toxity was demonstrated when high doses were administered intravenously or intaperitoneally in animal studies. Human studies have not shown any harm or benefit though one study demonstrated a clinically meaningful (though non-statistically significant) reduction in length of second stage and augmentation of labour in women taking raspberry leaf.

Conclusions

Many women use raspberry leaf in pregnancy to facilitate labour and birth. The evidence base supporting the use of raspeberry leaf in pregnancy is weak and further research is needed to address the question of raspberry leaf’s effectiveness.

Pregnancy and herbal medicines: An unnecessary risk for women's health-A narrative review

The indiscriminate use of herbal medicines to prevent or to heal diseases or even the use for questionable purposes such as weight loss has received both interest and scrutiny from the scientific community and general public alike. An increasing number of women put their own and the unborn child's health at risk due to a lack of knowledge about the phytochemical properties and adequate use of herbal medicine (phytomedicines or herbal supplements) and lack of communication with their healthcare provider. The purpose of this narrative review was to summarize the use of herbal medicines during pregnancy and their potential toxic effects to highlight the importance of caution when prescribing herbal medicines or supplements for women, because, in addition to suffering interactions and a great amount of information obtained in preclinical predictive studies, assessment of nephrotoxicity, neurotoxicity, hepatotoxicity, genotoxicity, and teratogenicity of traditional medicinal herbs still remains scarce in the clinical setting.

Herbal Therapy in Pregnancy-What to Expect when you Expect?

The use of herbal therapy in pregnancy is common for pregnancy related nausea, vomiting, gestational diabetes, anxiety, insomnia, and preparation for labor, as well as for treating infections. Many conventional drugs may interfere with fetal development and herbal products are considered to be safe. However, herbal therapy requires competent healthcare professional advice before prescribing. Knowledge about the possible adverse effects of active compounds of the herbs on pregnancy outcome is limited. Interference of herbal ingredients with conventional medication or the ailment should also not be excluded. For many herbal products, the pharmacological effect is not clinically proven, and the safe usage in pregnancy is not guaranteed. Here, based on published clinical trials, an overview is given of the efficacy and safety for fetal development and pregnancy outcome of the most frequently used herbs: ginger, cranberry, echinacea, mint, chamomile, valerian, flaxseed, tea and raspberry leaf.

Berry Leaves: An Alternative Source of Bioactive Natural Products of Nutritional and Medicinal Value

Berry fruits are recognized, worldwide, as “superfoods” due to the high content of bioactive natural products and the health benefits deriving from their consumption. Berry leaves are byproducts of berry cultivation; their traditional therapeutic use against several diseases, such as the common cold, inflammation, diabetes, and ocular dysfunction, has been almost forgotten nowadays. Nevertheless, the scientific interest regarding the leaf composition and beneficial properties grows, documenting that berry leaves may be considered an alternative source of bioactives. The main bioactive compounds in berry leaves are similar as in berry fruits, i.e., phenolic acids and esters, flavonols, anthocyanins, and procyanidins. The leaves are one of the richest sources of chlorogenic acid. In various studies, these secondary metabolites have demonstrated antioxidant, anti-inflammatory, cardioprotective, and neuroprotective properties. This review focuses on the phytochemical composition of the leaves of the commonest berry species, i.e., blackcurrant, blackberry, raspberry, bilberry, blueberry, cranberry, and lingonberry leaves, and presents their traditional medicinal uses and their biological activities in vitro and in vivo.

Immunohistochemical and functional studies on calcium-sensing receptors in rat uterine smooth muscle

1. Activation of calcium-sensing receptors (CaS) leads to relaxation of vascular smooth muscle. However, the role of CaS in uterine smooth muscle is unknown. Therefore the aim of the present study was to investigate the expression and function of CaS in the uterus. 2. The expression of CaS in the oestrogen-dominated rat uterus was investigated using immunohistochemistry. The effects of putative CaS ligands on oxytocin-induced contractions of longitudinally orientated uterine strips from oestrogen-dominated rats were determined at reduced extracellular Ca²⁺ concentrations using conventional organ bath techniques. 3. Immunohistochemical evidence showed the presence of CaS in the endometrium and smooth muscle layers of the rat uterus. Oxytocin-induced contractions were inhibited by cations (Gd³⁺ > Ca²⁺ = Mg²⁺), polyamines (spermine > spermidine) and the positive allosteric modulators cinacalcet and calindol. However (R)- and (S)-cinacalcet were equipotent, indicating a lack of stereoselectivity, and the negative allosteric modulator calhex-231 also caused dose-dependent relaxation. In addition, although intermediate-conductance calcium-activated potassium channels and cytochrome P450-dependent signal transduction have been implicated in CaS-induced relaxation of vascular smooth muscle, neither Tram-34 nor miconazole (1 μmol/L), which block these pathways, respectively, had any effect on the ability of cinacalcet to inhibit oxytocin-induced contractions. 4. Calcium-sensing receptors are expressed in smooth muscle layers of the rat uterus and their ligands produce potent relaxation of longitudinally orientated uterine strips. However, the pharmacological profile of inhibition of contractility by CaS ligands is not consistent with a role for CaS in the regulation of uterine contractility in the rat.