The effect of maternal malignancy on fertility, pregnancy, and neonatal outcomes

Sammanfattning: The aim of this thesis is to investigate whether a malignant disease in women increases the risk of fertility disturbances, pregnancy and delivery complications and also of adverse birth outcomes among their infants. By linkage between six national health registers, we obtained data for all children born in Sweden 1994-2011 and their mothers including information on malignancy diagnosis, method of conception (natural/ART), pregnancies, and health outcomes of the infants. In Papers I- III we studied the outcomes after a malignancy diagnosis of more than one year before delivery. We found increased risks of fertility disturbance and some pregnancy and delivery complications among these women. We also saw an increased risk of preterm birth and low birth weight among their infants and as a result of this an increased risk of neonatal morbidity. No increased risk of malformation was found after a history of malignancy. However, an increased malformation risk was seen after IVF and previous maternal malignancy. In Paper IV the focus was on women and their infants with a malignancy close to or during pregnancy. We observed a high incidence of prematurity and neonatal morbidity, especially when the malignancy was diagnosed during the second and third trimesters. An increased risk was also seen of relatively mild malformations after maternal malignancy within six months prior to pregnancy or during the first trimester. In conclusion, it is important that these women receive adequate information about potential risks but also reassurance from clinicians who provide counseling. During their pregnancies additional surveillance is possibly required.