Time to Pregnancy, Obstetrical and Neonatal Outcomes after Breast Cancer: A Study from the Maternity Network for Young Breast Cancer Patients

Abstract

Although an increasing number of young breast cancer (BC) patients have a pregnancy desire after BC, the time necessary to obtain a pregnancy after treatment and subsequent outcomes remain unknown. We aimed to determine the time to evolutive pregnancy in a cohort of BC survivors and subsequent obstetrical and neonatal outcomes. We analyzed BC patients treated at Institut Curie from 2005-2017, aged 18-43 years old (y.o.) at diagnosis having at least one subsequent pregnancy. 133 patients were included, representing 197 pregnancies. Mean age at BC diagnosis was 32.8 y.o. and at pregnancy beginning was 36.8 y.o. 71% pregnancies were planned, 18% unplanned and 86% spontaneous. 64% pregnancies resulted in live birth (n = 131). Median time from BC diagnosis to pregnancy beginning was 48 months and was significantly associated with endocrine therapy (p < 0.001). Median time to pregnancy was 4.3 months. Median time to evolutive pregnancy 5.6 months. In multivariate analysis, menstrual cycles before pregnancy remained significantly associated with time to pregnancy and endocrine therapy with time evolutive to pregnancy. None of the BC treatments (chemotherapy/endocrine therapy/trastuzumab) was significantly associated with obstetrical nor neonatal outcomes, that seemed comparable to global population. Our findings provide reassuring data for pregnancy counseling both in terms of delay and outcome.

Keywords: breast cancer; neonatal outcomes; obstetrical outcomes; time to pregnancy.

Figure 1

Characteristics of 197 pregnancies occuring after breast cancer in 133 patients. (A): Number of pregnancy by patient; (B): Age at BC diagnosis according to the spontaneous occurrence of the pregnancy or ART; (C): Age at pregnancy beginning according to the spontaneous occurrence of the pregnancy or ART; (D): Pregnancy outcomes; (E): Pregnancy outcomes by planned or unplanned nature of the pregnancy; (F): Pregnancy outcomes by age at pregnancy beginning; (G): Time from BC diagnosis to pregnancy beginning according to the use of endocrine therapy; (H): Time from BC diagnosis to pregnancy beginning by BC subtype. Effectives and percentages were removed from Figure 1E,F when absolute counts were 2 or below.

Figure 2

Time from pregnancy attempt to evolutive pregnancy begininng. (A). Histogram of distribution of time to evolutive pregnancy; Time to evolutive pregnancy according to age at pregnancy beginning (B), menstrual cycles before pregnancy attempt (C), BC subtype (D), tumor grade (E), previous chemotherapy (F), endocrine therapy (G), trastuzumab (H).

Figure 2

Time from pregnancy attempt to evolutive pregnancy begininng. (A). Histogram of distribution of time to evolutive pregnancy; Time to evolutive pregnancy according to age at pregnancy beginning (B), menstrual cycles before pregnancy attempt (C), BC subtype (D), tumor grade (E), previous chemotherapy (F), endocrine therapy (G), trastuzumab (H).

Figure 3

Obstetrical and neonatal outcomes on 131 evolutive pregnancies. (A): Obstetrical complications; (B): Histogram of delivery terms; (C): Apgar scores at 1 and 3 min (count and effectives); (D): Birth weight by delivery term; (E): Birth size by delivery term; (F): Cranial perimeter by delivery term; (G): Delivery term by previous cancer treatments; (H): Birth weight by previous cancer treatment; (I): Birth height by previous cancer treatments; (J): Head circumference (cm) by previous cancer treatments. Effectives and percentages were removed from Figure 3C when absolute counts were 2 or below.