Effect of Pregnancy on the Clinical Course of ITP Pregnant Women and Their Newborns. Resuts of a Spanish Case Series of 297 Primary ITP Pregnancies

Introduction:

Given that there is no large case-series, effect of pregnancy on the course of pre-existing primary immune thrombocytopenia (ITP) patients is unclear^1,2. Furthermore, outcome predictors evidence of neonates born to mothers with ITP is very scarce¹. Due to obvious ethical reasons, no clinical trial regarding ITP and pregnancy has been reported until recent days³. Nevertheless, the relationship between ITP and pregnancy is considered a "trending topic" nowadays. As it is the, until now, unknown safety and efficacy of new drugs as TPO mimetics in this setting^3-6.

Aims:

To evaluate outcome and global management of pregnancy and delivery on ITP women an on their offspring.

Methods:

Primary ITP was defined as a platelet count < 100 x 10⁹/L in the absence of other causes or disorders that may be associated with thrombocytopenia.

All women diagnosed of primary ITP from 2011 to 2016 in 24 Spanish Hematology Departments who had at least one pregnancy after ITP onset were included in this registry.

Results:

We included 297 primary ITP pregnancies from 204 women. At pregnancy diagnosis, we observed a majority of chronic ITP cases (71.9 %). At ITP diagnosis, median age of our case-series was 23 years (IQR, 18-31) and median platelet count was 18 x 10⁹/l (IQR, 6-36). Median time from ITP diagnosis to pregnancy was 162 months (IQR, 0-364). Median number of pregnancies prior to ITP diagnosis was 1 (IQR, 0-2) with 1 pregnancy (IQR, 1-2) after ITP diagnosis as a median.

51.6% of women received corticosteroids, immunoglobulins (IVIG) (16.6%), rituximab (7.1%) and/or splenectomy (8.7%) as ITP treatments between or before new pregnancies. On the other hand, 26.5% of women needed treatment for ITP during pregnancy, mainly steroids (13.9%) and IVIG (10.2%).

The median platelet-count nadir during pregnancy was 73 x 10⁹/l (IQR, 31-174). 135 (45.4%) pregnancies had less than 50 x 10⁹ platelets/l with 77 (25.9%) with less than 30 x 10⁹ platelets/l. 57 women (19.2%) exhibited hemorrhagic symptoms, being 30 (10.1%) of them severe bleedings.

Regarding type of delivery, this was vaginal in 187 (62.9%) of pregnancies. Median platelet count at delivery was 111 x 10⁹/l (IQR, 70-187). 47 patients (15.8 %) experienced 60 bleeding episodes. We only observed 52 cases (19.5%) of neonatal thrombocytopenia among 266 living newborns.

Conclusions:

Our results are comparable to previously reported^1,2. No severe bleeding complications during pregnancy and/or delivery were observed in our study. Rate of neonatal thrombocytopenia, and therefore, newborn bleeding is low.