Notice: You are viewing an unstyled version of this page. Are you using a very old browser? If so, please consider upgrading

Pituitary Tumours

Key points

  • Pituitary tumours produce hormones that can have a detrimental effect on pregnancy.
  • The pituitary enlarges in size during pregnancy; if tumour is present it may compress surrounding structures, including the optic nerve.
  • This will be the first national study to evaluate maternal and fetal mortality and morbidity of pituitary tumours in pregnancy.
  • This information will be used to develop guidelines for the management of women with pituitary tumours in pregnancy.

Surveillance Period

March 2010 - March 2013


Pituitary Tumours are rare and complicate approximately 1 in 4500 pregnancies in the UK. These tumours often secrete hormones, which in excess can have devastating effects on the mother and the unborn baby. In addition, many pituitary tumours require treatment with specific drugs or surgery, and this can also result in adverse outcomes for the fetus or neonate.

Macroprolactinoma is a benign tumour of the pituitary that is 1cm or more in diameter and produces a hormone called prolactin. The risk of enlargement of untreated macroprolactinoma in pregnancy is approximately 26%, compared to 3% in women previously treated with surgery and/ or radiation[1]. The treatment of choice is cabergoline, which has been used in over 350 pregnancies[2][3], despite guidance that it should not be used in pregnancy[4]. The guidance is based on studies in non-pregnant patients that demonstrated an increased cardiac fibrosis. However, there has been no documented increase in congenital abnormalities, or of maternal or fetal cardiac fibrosis, associated with the low dose of cabergoline used in pregnancy. Alternate medications have not been widely used in pregnancy.

Pituitary tumours that secrete excess hormones are associated with a higher incidence of mortality and morbidity. Cushing's disease and acromegaly are both associated with an increased incidence of hypertension (potentially leading to pre-eclampsia), diabetes and cardiac failure[1]. Cushing's disease is associated with high fetal morbidity (spontaneous abortion 5%, stillbirth 6% and prematurity 43%)[5]. There is very little literature on the use of medication in the management of these conditions in pregnancy.

Following this study we will be able to provide comprehensive information on maternal/fetal outcome related to medications used to treat pituitary tumours and this will be used as the basis for the development of clinical management guidelines.


To use the UK Obstetric Surveillance System to describe the maternal and fetal outcomes in women with pituitary tumours in pregnancy

Research questions

  • What proportion of women with pituitary tumours have significant tumour expansion during pregnancy?
  • What are the current monitoring and management strategies for women with pituitary tumours during pregnancy?
  • What are the outcomes of pregnancy for mother and infant?

Case definition

All women in the UK with a pituitary tumour in pregnancy excluding a microprolactinoma (a prolactin-secreting tumour less than 1.0cm diameter).

This will include women diagnosed in pregnancy and those diagnosed pre pregnancy with a macroprolactinoma, Cushing disease, Acromegaly, thyrotrophinomas or non-functioning pituitary tumours.



Ethics committee approval

The study has been approved by the Riverside REC (study ref 09/H0718/63).


K Lambert, M Dhanjal, C Williamson, Imperial College Healthcare NHS Trust.

D McCance, Royal Victoria Hospital, Belfast.

Download the Data Collection Form (DCF)

UKOSS Pituitary Tumours Form


  1. a, b Molitch ME. Pituitary tumors and pregnancy. Growth Horm IGF Res. 2003 Aug;13 Suppl A:S38-44.
  2. ^ Robert E, Musatti L, Piscitelli G, Ferrari CI: Pregnancy outcome after treatment with the ergot derivative, cabergoline. Reprod Toxicol 10: 333, 1996.
  3. ^ Colao A, Abs R, Barcena DG, Chanson P, Paulus W, Kleninberg DL. Pregnancy outcomes following cabergoline treatment: extended results from a 12-year observational study. Clin Endocrinol (Oxf). 2008 Jan;68(1):66-71.
  4. ^ Ergot-derived dopamine agonists: risk of fibrotic reactions in chronic endocrine uses. Drug and safety update. Vol 2 Issue 3 Oct 2008.
  5. ^ Lindsay JR, Jonklaas J, Oldfield EH, Nieman LK. Cushing's syndrome during pregnancy: personal experience and review of the literature. J Clin Endocrinol Metab. 2005 May;90(5):3077-83.

Updated: Tuesday, 17 January 2023 18:07 (v5)