Women diagnosed with Hodgkin lymphoma during pregnancy can be successfully treated without harming their unborn child, a study in The Lancet Haematology confirms.

A retrospective study of 134 pregnant women diagnosed between 1969 and 2018 found that after the first trimester, chemotherapy can be effective with few adverse effects for the foetus.

The results should reassure both doctors and patients that treatment during the second and third trimesters of pregnancy – an option that became more common over the study period –  is safe and can produce good outcomes, clinicians said.

In addition, deferral of treatment might be an option in selected patients – such as those diagnosed in the final weeks of pregnancy – the paper said.

Among those included in the study, 72 (54%) patients initiated antenatal chemotherapy, 56 (42%) did not receive treatment during pregnancy, and 6 (4%) received only radiotherapy, the researchers reported.

Patients who were treated antenatally had more obstetric complications – most commonly preterm contractions (12% vs 7%) and preterm rupture of membranes (5% vs 0).

But the incidence of neonates who were small for gestational age did not differ between those exposed to chemotherapy and those who were not and there was no difference in the proportions admitted to neonatal intensive care.

The researchers did find that birthweight percentiles were lower in neonates prenatally exposed to chemotherapy.

A further comparison of 77 pregnant patients with 211 non-pregnant Hodgkin lymphoma patients showed similar levels of 5-year progression free survival and 5-year overall survival was 97·3% vs and 98·4%

Writing in The Lancet Haematology, the international team of researchers concluded that treatment with standard doses of doxorubicin, bleomycin, vinblastine, and dacarbazine during pregnancy for Hodgkin lymphoma does not affect maternal survival.

But that the potential effect on foetal growth highlights the need for “regular obstetric follow-up in this high-risk population”.

Professor Simon Rule, professor in haematology at the University of Plymouth told the limbic that the study provided reassuring data about an approach that is now generally regarded as standard.

“We know chemotherapy is fine after the first trimester without long term issues for the baby so this provides more evidence to reassure everyone in that regard.

“It is perhaps most useful for the patients themselves,” he added.