Over the past 20 years, medical records of pregnant women with type 1 diabetes have shown an increase in blood pressure with many women falling into the hypertensive group during pregnancy. However, there are no indications of increased hypertensive complications in the same group of women. Researchers published the results of the hypertension study in the journal Diabetic Medicine.

Medical files for more than 1,000 women were reviewed for the study. All women were diagnosed with type 1 diabetes prior to pregnancy and gave birth to a singleton. No multiples pregnancies were included in the study. Researchers found no indication that hypertensive complications increased during the study period, but there was a marked increase in both systolic and diastolic readings across all three trimesters. The percentage of patients measuring systolic readings in excess of 130 mmHg or diastolic readings in excess of 80 mmHg increased in trimesters one, two and three by 8%, 9%, and 14%, respectively.

Blood pressure is clearly increasing in women with type 1 diabetes during pregnancy, but there does not appear to be any clinical manifestation in terms of maternal/fetal complications associated with the increase.

Source: Klemetti MM, Teramo K, Nuutila M, Tikkanen M, Hiilesmaa V, Laivuori H. Blood pressure levels but not hypertensive complications have increased in Type1 diabetes pregnancies during 1989-2010. Diabet Med. 2013 May 10. doi: 10.1111/dme.12224.