The occurrence of pregnancy in women with brain tumors confronts both patients and physicians with difficult decision making at each stage of pregnancy. We studied the course of events of nine pregnancies in seven women with low-grade glioma in our hospital over a 10 year period. Five patients had a surgical resection, one a biopsy and one woman was followed by wait-and-see policy before pregnancy. In two women, a therapeutic abortion was carried out in the first trimester because of signs of progression, necessitating surgical removal of the tumor. In the other five women pregnancy had an uncomplicated course. Based on a literature review, we found 28 women diagnosed with a known glioma before becoming pregnant. All pregnancies but one, were uneventful and all women had a normal delivery, including the seven cases with exposure to chemotherapy and in whom healthy babies were born. A total of 75 pregnant women were identified in whom new onset glioma developed, which was high-grade in 56 %, and becoming symptomatic in 51 % during the third trimester, usually by focal neurological deficits. We conclude that in relation to pregnancy, low-grade gliomas are more often seen in women already known with a brain tumor, while high-grade gliomas represent more frequently a new onset phenomenon. Based on these observations, guidelines are given on initiation of antitumor therapy during pregnancy, seizure management, counseling on therapeutic abortion, and on the timing and choice of obstetrical interventions.