Rates of childbirth amongst women with myeloproliferative neoplasms

Pregnancies in patients with myeloproliferative neoplasms (MPN) are often associated with poorer outcomes, including an increased risk of pre-eclampsia, as well as maternal and fetal morbidity. However, there are limited data on childbearing and birthrates amongst patients with MPN compared with the general population.¹

Here, we summarize a retrospective analysis by Landtblom et al.¹ published in Leukemia on the childbirth rates in women with MPN.

Study design¹

• Women with an MPN diagnosis, aged between 15 and 44 years, were selected from healthcare registers in Sweden.
• Patients were age-matched in a ratio of 1:4 with controls from the general population.
• The main outcome was time to first live childbirth post-MPN diagnosis.
  • Subgroup analyses were performed by age and MPN subtype.
• Secondary outcomes were miscarriage rate, and stillbirth pre- and post-MPN diagnosis.

Key findings¹

• A total of 1,141 patients with MPN and 4,564 control participants were included in this study.
• A 22% decreased childbirth rate was observed amongst the patients with MPN, compared with the control cohort (Figure 1).
  • Essential thrombocythemia was the only subtype with similar childbirth rates to the control group.
  • Childbirth rates were significantly reduced in all other MPN subtypes.
  • Women aged 15–25 years were observed to have significantly reduced birthrates compared with the control group.
  • No significant differences in birthrates were observed in any other age category.
• At the time of diagnosis, 61% of women with MPN had given birth to at least one child, compared with 67.3% in the age-matched controls (p < 0.001).
• With mean follow-up of 5 years, the risk of miscarriage was not significantly increased amongst patients with MPN compared with the control group; hazard ratio 1.25 (95% confidence interval [CI], 0.89–1.76).
  • However, women with MPN were more likely to have experienced a previous stillbirth, with fewer children in total.

CI, confidence interval; ET, essential thrombocythemia; MPN-U, myeloproliferative neoplasms-unclassified; PMF, primary myelofibrosis; PV, polycythemia vera.
*Data from Landtblom, et al.¹

Key learnings

Overall, childbirth rates were lower amongst all subtypes of MPN compared with the general population, with the exception of essential thrombocythemia. Women with MPN also had fewer children than age-matched controls and were more likely to have had stillbirths prior to MPN diagnosis. The risk of miscarriage before or after diagnosis of MPN was similar to the general population group. Optimizing MPN management before and during pregnancy is crucial to improve birthrates and minimize the risk of complications and necessitates continued international collaboration on treatment guidelines.