Future pregnancy outcome in unexplained recurrent first trimester miscarriage

The future pregnancy outcome of 201 consecutive women, median age 34 years (range 22-43), with a history of unexplained recurrent first trimester miscarriage (median 3; range 3-13), was studied. All women and their partners had normal peripheral blood karyotypes; none had antiphospholipid antibodies and none hypersecreted luteinizing hormone (LH). No pharmacological treatment was prescribed and early pregnancy supportive care was encouraged. Women aged < or = 30 years had a subsequent miscarriage rate of 25% (14/57) which rose to 52% (13/25) in women aged > or = 40 years (P = 0.02). After three consecutive miscarriages, the risk of miscarriage of the next pregnancy was 29% (34/119) but increased to 53% (9/17) after six or more previous losses (P = 0.04). A past history of a livebirth did not influence the outcome of the next pregnancy. Supportive care in early pregnancy conferred a significant beneficial effect on pregnancy outcome. Of 160 women who attended the early pregnancy clinic, 42 (26%) miscarried in the next pregnancy compared with 21 out of 41 (51%) who did not attend the clinic (P = 0.002). After thorough investigation, women with unexplained recurrent first trimester miscarriage have an excellent pregnancy outcome without pharmacological intervention if offered supportive care alone in the setting of a dedicated miscarriage clinic.