Bromocriptine in pregnancy: safety aspects

Advances in the treatment of prolactinomas

Prolactinomas account for approximately 40% of all pituitary adenomas and are an important cause of hypogonadism and infertility. The ultimate goal of therapy for prolactinomas is restoration or achievement of eugonadism through the normalization of hyperprolactinemia and control of tumor mass. Medical therapy with dopamine agonists is highly effective in the majority of cases and represents the mainstay of therapy. Recent data indicating successful withdrawal of these agents in a subset of patients challenge the previously held concept that medical therapy is a lifelong requirement. Complicated situations, such as those encountered in resistance to dopamine agonists, pregnancy, and giant or malignant prolactinomas, may require multimodal therapy involving surgery, radiotherapy, or both. Progress in elucidating the mechanisms underlying the pathogenesis of prolactinomas may enable future development of novel molecular therapies for treatment-resistant cases. This review provides a critical analysis of the efficacy and safety of the various modes of therapy available for the treatment of patients with prolactinomas with an emphasis on challenging situations, a discussion of the data regarding withdrawal of medical therapy, and a foreshadowing of novel approaches to therapy that may become available in the future.

Guidelines of the Pituitary Society for the diagnosis and management of prolactinomas

In June 2005, an ad hoc Expert Committee formed by the Pituitary Society convened during the 9th International Pituitary Congress in San Diego, California. Members of this committee consisted of invited international experts in the field, and included endocrinologists and neurosurgeons with recognized expertise in the management of prolactinomas. Discussions were held that included all interested participants to the Congress and resulted in formulation of these guidelines, which represent the current recommendations on the diagnosis and management of prolactinomas based upon comprehensive analysis and synthesis of all available data.

Drug Insight: cabergoline and bromocriptine in the treatment of hyperprolactinemia in men and women

Prolactinoma is the most frequent pituitary tumor histotype. Men generally have macroadenomas whereas women generally have microadenomas. The major objectives of treating prolactinomas are to suppress excessive hormone secretion and its clinical consequences, to remove the tumor mass while preserving the residual pituitary function, and possibly to prevent disease recurrence or progression. Primary therapy of prolactinomas is based on use of dopamine-receptor agonists. Bromocriptine induces normalization of prolactin levels in 80-90% of patients with microprolactinomas and approximately 70% of those with macroprolactinomas. Tumor-mass shrinkage and improvement of visual-field defects are found in the majority of treated macroprolactinomas, but bromocriptine often causes side effects. Cabergoline is very effective and well tolerated in more than 90% of patients with either microprolactinomas or macroprolactinomas. Cabergoline treatment also induces tumor shrinkage in the majority of patients with macroprolactinomas. Tumor shrinkage is more evident if patients have not previously been treated with other dopamine agonists. Fewer results are available for men than for women, but there is no evidence that men are less responsive to dopamine agonists than are women.

[Pharmacotherapy of pituitary diseases]

Successful pharmacotherapy of pituitary hormonal excess is established only in the treatment of acromegaly (dopamine agonists, somatostatin analogues, GH-receptor-antagonists) and of prolactinomas (dopamine agonists). Gold standard in the treatment of acromegaly is transsphenoidal pituitary surgery, while in prolactinomas, surgery is indicated only in exceptional cases. Substitution of pituitary insufficiency offers the patients a normal quality of life. Substitution of the cortico- and thyrotrope axis with hydrocortisone and levothyroxine is vital. In women, substitution of the gonadotrope axis should be performed up to menopause (estrogen/gestagen). In men, substitution should be performed lifelong (trans-dermal testosterone body patches, testosterone gel, testosterone undecanoate/enanthate). To achieve fertility, gonadotropins or pulsatile GnRH therapy has very good results. Especially in younger patients, substitution of growth hormone may be useful (somatropin).

Quand et comment traiter une hyperprolactinémie ?

Hyperprolactinemia affects the gonadotropic axis. Its results in women include amenorrhea, menstrual disorders and galactorrhea; in men, the frequency of macroadenomas tends to lead to problems related to sexual performance or tumor volume. Radioimmunoassays make diagnosis easy. Secondary causes of hyperprolactinemia, drug reactions in particular, must be ruled out before MRI exploration to look for a pituitary tumor. First-line treatment of prolactin adenomas is based on the use of dopaminergic agonists, especially cabergoline, because of their excellent efficacy and the risk of relapse following surgery. For patients who wish to become pregnant, the dopaminergic agonist must be continued during pregnancy for those with macroadenoma and withdrawn for women with microadenoma. When hyperprolactinemia is induced by anti-psychotic agents, treatment requires an in-depth assessment.

Prolactinomas and pregnancy

Prolactinomas are the most frequent pituitary tumors. Treatment of infertility in such tumors usually is very successful. On the other hand, reports of pituitary tumor growth during pregnancy have been described since bromocriptine started to be used. Since then, dopamine agonists (DA) have been increasingly used as the first-choice treatment of prolactinomas, with surgery being reserved for resistance or persistent intolerance to DA or for special situations. More recently other DA, such as quinagolide and cabergoline have shown better tolerance than bromocriptine with similar or greater efficacy. Cabergoline is now the first choice drug but its use in pregnancy is still under evaluation. We followed 71 term pregnancies in women bearing microprolactinomas. Of the 22 patients with previous surgery, none presented symptoms of tumor growth. Of the 41 pregnant patients treated with bromocriptine alone, only one (2.4%) presented with headaches, which regressed with drug reintroduction. Fifty one term pregnancies in patients with macroprolactinomas were followed by us. Of those, 21 were in patients with previous surgery and none of them presented clinical evidence of tumor growth. On the other hand, of the 30 patients treated only with pre-gestational bromocriptine, 11 (37%) manifested complaints related to tumor growth. A non-hormonal contraceptive should be the use along with a DA drug until tumor shrinkage within sellar boundaries has been evidenced. After pregnancy has been confirmed, the DA can be withdrawn and the patient must be closely followed. If tumor expansion is suspected, confirmation can be made through MRI and by visual field testing. Reintroduction of bromocriptine in such cases can lead to tumor reduction and clinical improvement. Surgery can also be employed as treatment for symptomatic tumor growth in pregnancy.

Thyroid disease and other endocrine disorders in pregnancy

Endocrine disorders, in particular, thyroid disorders, are common in pregnancy. The endocrine adaptation to pregnancy, need for adequate iodine supplementation, and thyroxine replacement are presented. In addition, autoimmune diseases of the thyroid and pituitary that may occur subsequent to the immune changes of pregnancy and the postpartum period are discussed. A brief account of the presentation of other endocrine disorders (ie, pituitary,parathyroid, calcium, adrenal and gonadal disorders) also is given, along with their evaluation and management.

Hyperprolactinemia: pathophysiology and management

Hyperprolactinemia is commonly found in both female and male patients with abnormal sexual and/or reproductive function or with galactorrhea. If serum prolactin levels are above 200 microg/L, a prolactin-secreting pituitary adenoma (prolactinoma) is the underlying cause, but if levels are lower, differential diagnoses include the intake of various drugs, compression of the pituitary stalk by other pathology, hypothyroidism, renal failure, cirrhosis, chest wall lesions, or idiopathic hyperprolactinemia. When a pituitary tumor is present, patients often have pressure symptoms in addition to endocrine dysfunction, such as headaches, visual field defects, or cranial nerve deficits. The large majority of patients with prolactinomas, both micro- and macroprolactinomas, can be successfully treated with dopaminergic drugs as first-line treatment, with normalization of prolactin secretion and gonadal function, and with significant tumor shrinkage in a high percentage of cases. Surgical resection of the prolactinoma is the option for patients who may refuse or do not respond to long-term pharmacological therapy. Radiotherapy and/or estrogens are also reasonable choices if surgery fails. In patients with asymptomatic microprolactinoma no treatment needs to be given and a regular follow-up with serial prolactin measurements and pituitary imaging should be organized. Currently, the most commonly used dopamine agonists are bromocriptine, pergolide, quinagolide and cabergoline. When comparing the plasma half-life, efficacy and tolerability of these drugs, cabergoline seems to have the most favorable profile, followed by quinagolide. Ifprolactin levels are well controlled with dopamine agonist therapy, gradual tapering of the dose to the lowest effective amount is recommended, and in a number of cases medication can be stopped after several years. Evidence to date suggests that cabergoline and quinagolide appear to have a good safety profile for women who wish to conceive, but hard evidence proving that dopamine agonists do not provoke congenital malformations when taken during early pregnancy is currently only available for bromocriptine. Once pregnant, dopamine agonist therapy should be immediately stopped, unless growth of a macroprolactinoma is likely or pressure symptoms occur. At our institution patients with symptomatic prolactinomas, both micro- and macroadenomas, are treated with cabergoline as the first-line aproach. In the small group of patients who do not respond to this treatment, or who refuse long-term therapy, surgery is offered. Radiotherapy is given if both pharmacologic therapy and surgery fail.

Medical management of prolactin-secreting pituitary adenomas

Prolactinomas are a common cause of reproductive/sexual dysfunction. Once other causes of hyperprolactinemia have been excluded with a careful history and physical examination, routine chemistries, a pregnancy test and a TSH, imaging with MRI or CT will delineate the size and extent of the tumor. Medical therapy is the initial treatment of choice. When infertility is the primary indication for treatment, bromocriptine use has an extensive safety experience and is preferred. However, for other indications, cabergoline appears to be more efficacious and better tolerated. Transsphenoidal surgery remains an option, especially for patients with microadenomas, when medical therapy is ineffective.

Medical management of pituitary adenomas: the special case of management of the pregnant woman

The development of efficacious surgical and medical therapies for pituitary adenomas as well as the improvement of hormone therapy for ovulation induction has made pregnancy possible for women harboring pituitary tumors. However, gestational risks due to the possibility of tumor growth during pregnancy, mainly in women with macroadenomas, raise a concern. Bromocriptine has a well-established role for prolactinoma treatment before and during pregnancy, even when a symptomatic tumor increase occurs. It can also be used in acromegaly, despite its poorer results. Somatostatin analogs have been used in acromegaly even during pregnancy with uneventful outcomes, but their safety in pregnancy is not well established, yet. The largest experience with medical treatment for Cushing's disease during pregnancy involves metyrapone, a steroidogenesis inhibitor, without descriptions of congenital abnormalities. Concerning clinically non-functioning pituitary tumors, ovulation induction or even in vitro fertilization are frequently needed. The purpose of this review is to provide an update on therapeutic strategies to restore fertility as well as gestational and post-gestational management of patients with pituitary adenomas, focusing mainly on the role of medical treatment for different tumor types.

Current management of prolactinomas

Prolactinomas constitute the largest group of pituitary adenomas in autopsy series. However, their relative incidence in recent surgical series is much less impressive since medical treatment with dopamine agonists is routinely employed, which in many cases leads to tumor shrinkage and normalization of prolactin levels. The clinical symptoms of hyperprolactinemia are menstrual dysfunction and galactorrhea in women and loss of libido and potency in men. Prolactinomas may present also as space occupying sellar mass lesions impinging on the adjacent structures like the pituitary gland, cavernous sinus and optic nerves. The standard primary treatment is medical by dopamine agonists. Prolactinomas are the prototype of tumors, the growth of which can be reliably and safely inhibited by specific drugs other than cytostatic chemotherapy. These unfortunately have side effects, like orthostatic hypotension, nausea and vomiting. The effects induced by dopamine agonists are suppressive but not tumoricidal. Thus, the therapeutic effect is only maintained as long as the drug is administered. Consequently. in most cases, treatment has to be continued life-long with a few exceptions, in whom normoprolactinemia persists even after discontinuation of dopamine agonists. Main indications of surgery in prolactinomas are intolerance of the medication, and tumors not responding to dopamine agonists. Occasionally, these may ultimately require radiation therapy. Remission rates in large series of surgically treated prolactinomas vary between 54% and 86%. In our consecutive series of 540 surgically treated prolactinomas, the normalization rate after transsphenoidal surgery basically depended on the preoperative prolactin levels, tumor size and extension. The remission rate of 82% in microprolactinomas with initial prolactin levels <200 ng/ml would even in small adenomas make one consider surgical treatment as an interesting alternative to long-term medical treatment.

Disorders of prolactin secretion

Prolactinomas are a common cause of reproductive/sexual dysfunction. Once other causes of hyperprolactinemia have been excluded with a careful history and physical examination, routine chemistries, and an assay for TSH, MR imaging, or CT will delineate the size and extent of the tumor. Medical therapy is the initial treatment of choice. When infertility is the primary indication for treatment, bromocriptine use has an extensive safety record and is preferred. For other indications, cabergoline seems to be more efficacious and better tolerated. Transsphenoidal surgery remains an option, especially for patients with microadenomas, when medical therapy is ineffective.

Medical treatment of prolactinomas

Prolactinomas are a common cause of reproductive and sexual dysfunction. Once other causes of hyperprolactinemia have been excluded with a careful history, physical examination, routine chemistries, and a TSH, MR imaging or computerized tomography will delineate the size and extent of the tumor. Medical therapy is the initial treatment of choice. When infertility is the primary indication for treatment, bromocriptine use has an extensive safety experience and is preferred. For other indications, however, cabergoline appears to be more efficacious and better tolerated. Transsphenoidal surgery remains an option, especially for patients with microadenomas, when medical therapy is ineffective.

Pregnancy outcome after treatment with the ergot derivative, cabergoline

The goal of this article is to assess the reproductive safety of cabergoline, a new ergot derivative proposed in hyperprolactinemic disorders. Investigated in different animal species, the drug showed no teratogenic or embryotoxic effects on rabbits. Considering the dose envisaged for humans, large safety margins exist. Our sample consists of 226 pregnancies occuring in 205 women. Follow-up is available for 204. There were 24 miscarriages and three abortions induced because of major malformations (one Down syndrome in a 42-year-old woman, one limb-body wall complex, one hydrocephalus). Two of the 148 single liveborn infants had significant malformations: one megaureter, one scaphocephaly. This series shows no increase in miscarriage rate, a distribution of birthweights and sex ratio within the expected range, and no increased rate of congenital malformations. Follow-up of babies, limited to 107 cases, thus far indicates normal physical and mental development.

The association between birth weight, placenta weight, pregnancy duration, subfecundity, and child development

It is well known that very low birth weight and preterm birth are risk indicators for delayed child development. It is the purpose of this study to estimate the association between birth weight, placenta weight, and gestational age in consecutive pregnancies which survived till after 28th week of gestation. The association between fecundity and child development is also studied. Data stem from pregnant women in a well defined regional area in Denmark (Odense) who participated in a concerted action on moderate alcohol consumption in pregnancy (EuroMac). All pregnant women with an alcohol consumption of 5 drinks or more per week or more in the first trimester were selected for the study in 1988 to 1989. A one to one match of pregnant woman was selected among the remaining pregnant woman based upon expected time of delivery and age. Altogether 326 women were selected for the study and the two groups are combined since alcohol intake in the measured dose range had no association with child development. The newborn went through two psychological tests at 18 month (the Bayley test) and again at 42 months of age (the Griffiths' test). Two hundred fiftynine pairs of mothers and children participated in all parts of data collection. Birth weight and gestational age was associated with the psychological scoring in the test performed at 18 and 42 months of age, especially the psychomotor index. Especially newborns with low birth weight and high placenta weight had low score values on mental development indices. No association was seen between a measure of fecundity (waiting time to pregnancy) and reduced child development.

Cocaine abuse during pregnancy: psychiatric considerations

Cocaine abuse is an increasing problem in the obstetric population. It not only poses a health risk to the pregnant woman, but can precipitate premature labor and abruptio placentae, and has been associated with a number of physical and behavioral problems in the newborn. Evaluation and management of the pregnant cocaine abuser is similar in most respects to that of nonpregnant adults, but diagnosis, psychotherapy, and pharmacotherapy is strongly influenced by the pregnancy. This article describes the risks of cocaine use during pregnancy and outlines the evaluation and management of the pregnant cocaine abuser.

[Treatment of prolactinoma]

Prolactinomas rank first in frequency among hormone-secreting pituitary adenomas, but their management remains controversial. The authors present a review of the literature concerning the various therapeutic methods used and their results. As regards microadenomas, opinions are divided since the results obtained with bromocriptine and with selective adenomectomy are about the same. As regards macroadenomas, surgery exposes to more frequent complications and above all to recurrences. The majority of authors is in favour of bromocriptine first followed, if necessary, by surgical excision. Pregnancy may accelerate the development of prolactinomas. This risk is minimal with microadenomas and more real with macroadenomas, requiring more radical treatment before pregnancy and close monitoring.

Case-control cytogenetic study in offspring of mothers treated with bromocriptine during early pregnancy

The distribution of modal and non-modal karyotypes was examined in mitoses of lymphocyte cultures of 31 children who had been exposed to bromocriptine in utero, and in 31 matched controls. No mosaicism was diagnosed. Furthermore, no more hypomodal cells occurred in the study group than in the control group.