International consensus report
ASH
BSCH
Japan
First-line
Prednisone/prednisolone (10–20 mg/day)
IVIG (dose not specified)
IV anti-D
Prednisone/prednisolone (1 mg/kg/day)
IVIG (1 g/kg for 2 days)
Prednisone/prednisolone (1 mg/kg/day)
IVIG (0.4 g/kg/day for 5 days or 1 g/kg/day for 2 days)
Prednisolone (10–20 mg/day) * 0.5–1 mg/kg/day can be also considered for severe cases.
IVIG (0.4 g/kg/day for 3–5 days)
Second-line
High-dose IV methyl-prednisolone (1000 mg) ± IVIG or azathioprine
Splenectomy (second trimester)
Corticosteroids and IVIG
Splenectomy (second trimester)
High-dose IV methylprednisolone (1000 mg) ± IVIG
Azathioprine
Splenectomy (second trimester)
Splenectomy should be avoided
Third-line
Cyclosporine, dapsone, TPO-R agonists, rituximab (not recommended but use in pregnancy described)
As far as the choice of corticosteroids is concerned, prednisone or prednisolone is preferred to dexamethasone, which crosses the placenta more readily [3]. While the ASH guideline recommends a starting dose of prednisone 1 mg/kg daily, there is no evidence that a higher starting dose is better than a lower dose [3]. Therefore, other experts recommend a starting dose of 0.25–0.5 mg/kg daily. In fact, the Japanese consensus report recommends 10–20 mg/day as a starting dose [5] since a Japanese nationwide study revealed that prednisolone dose of 15 mg/day or more might be associated with premature delivery, preeclampsia, or congenital abnormalities [6]. The international consensus report also recommends this lower starting dose [2].
The conventional dose of IVIG is 0.4 g/kg/day for 5 days, which is recommended in Japanese consensus report [5]. Alternatively, 1 g/kg/day for 2 days can be considered according to ASH and BSCH guidelines [3, 4]. The duration of response to IVIG is usually 2–3 weeks [2], and therefore after an initial response, repeat infusions might be required to prevent bleeding symptoms and keep an adequate platelet count if the patient should be managed only with IVIG.