Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jan 6:4:40.
doi: 10.3310/nihropenres.13652.2. eCollection 2024.

The UK Breast Cancer in Pregnancy (UKBCiP) Study. Incidence, diagnosis, management and short-term outcomes of breast cancer first diagnosed during pregnancy in the United Kingdom: A population-based descriptive study

Claudia Hardy  1 , Andrew Brand  2 , Julie Jones  3 , Marian Knight  4 , Philip Banfield  1
Affiliations

The UK Breast Cancer in Pregnancy (UKBCiP) Study. Incidence, diagnosis, management and short-term outcomes of breast cancer first diagnosed during pregnancy in the United Kingdom: A population-based descriptive study

Claudia Hardy et al. NIHR Open Res. .

Abstract

Background: The incidence of breast cancer first arising during pregnancy has been estimated in several countries to be 2.4-7.8/100,000 births, but has not been established in the United Kingdom (UK). We aimed to estimate the incidence of breast cancer diagnosed during pregnancy in the UK and to describe its management and short-term outcomes for mothers and babies.

Methods: This population-based descriptive study used the UK Obstetric Surveillance System (UKOSS). Cases were prospectively identified through monthly UKOSS mailings to all UK consultant-led maternity units. All cases of breast cancer diagnosed first during pregnancy, between October 1, 2015, and September 30, 2017, were eligible, with 84 confirmed cases analysed. Women with breast cancer diagnosed before pregnancy or with a recurrence were excluded. The primary outcomes were the incidence of breast cancer first diagnosed during pregnancy, maternal mortality, severe maternal morbidity, perinatal mortality, and severe neonatal morbidity.

Results: The incidence was 5.4/100,000 maternities (95% CI 4.37, 6.70). Nine women (11%) had undergone in vitro fertilisation (IVF), compared with a contemporaneously estimated 2.6% IVF pregnancies in the UK. During pregnancy, 30 women (36%) underwent surgery and 37 (44%) received chemotherapy. Three women had major maternal morbidity during pregnancy. Two women died and two perinatal deaths occurred.

Conclusions: The incidence of breast cancer arising in pregnancy in the UK is similar to that reported elsewhere. The higher proportion of IVF pregnancies among affected women needs further investigation, as it may not be entirely explained by relatively advanced maternal age. With caveats, management followed that outside pregnancy, but there was considerable variation in practice. Although short-term outcomes were generally good for mothers and babies, a larger prospective study is required. Iatrogenic pre-term delivery and its associated risks to the infant can often be avoided; treatment was administered during pregnancy without evidence of harms to the infant.

Keywords: Breast cancer; incidence; pregnancy.

Plain language summary

Breast cancer is the most common cancer in the UK. We wanted to know how common it is for women in the UK to be diagnosed with breast cancer for the first time while pregnant, and what clinical treatment these women received. Every month, all maternity units in the UK send anonymous information about pregnant women who have certain rare conditions diagnosed to a central database, the UK Obstetric Surveillance System (UKOSS). We looked at all the information that UKOSS collected during a two-year period about women who were newly diagnosed with breast cancer during pregnancy. During the two years, 84 pregnant women were diagnosed with breast cancer for the first time. Based on this, we estimated that there were 5.4 new diagnoses of breast cancer per 100,000 women giving birth in the UK. This is similar to the numbers that researchers have estimated in other countries. The women received broadly similar clinical treatment to non-pregnant women with breast cancer. However, treatment varied a lot between individuals. More diagnosed women than would be expected had undergone IVF. This finding might be partly related to the older age of the pregnant women diagnosed with breast cancer. However, this finding needs further investigation. It is easy to dismiss breast cancer symptoms during pregnancy as normal pregnancy breast changes. This can delay diagnosis. Although breast cancer during pregnancy is rare, women should discuss any symptoms with their healthcare providers. Midwives should be alert to the possibility of breast cancer and consider investigating symptoms further.

PubMed Disclaimer

Conflict of interest statement

No competing interests were disclosed.

Similar articles

See all similar articles

References

    1. Office for National Statistics: Cancer registration statistics, England: 2017. 2019; [Cited 2024 April 16]. Reference Source
    1. Information Services Division: Cancer incidence and prevalence in Scotland (to December 2017). 2019; [Cited 2024 April 16]. Reference Source
    1. NHS Digital: NHS maternity statistics, England 2017–18.2018; [Cited 2024 April 16]. Reference Source
    1. Andersson TM, Johansson ALV, Hsieh CC, et al. : Increasing incidence of pregnancy-associated breast cancer in Sweden. Obstet Gynecol. 2009;114(3):568–572. 10.1097/AOG.0b013e3181b19154 - DOI - PubMed
    1. Lyons TR, Schedin PJ, Borges VF: Pregnancy and breast cancer: when they collide. J Mammary Gland Biol Neoplasia. 2009;14(2):87–98. 10.1007/s10911-009-9119-7 - DOI - PMC - PubMed

LinkOut - more resources