Complications of pregnancy following threatened abortion

Summary

Fifty mothers (study group) who suffered a threatened abortion whose pregnancy continued at least till 28 weeks gestation were compared to the next matched delivered mother (control group). Study mothers were at risk of perinatal death from abruptio placentae, post-partum haemorrhage, retained placentas and a small baby. Those study mothers with severe symptoms delivered earlier.

Abortion is the commonest cause of pregnancy failure. Statistics from our hospital (for the last decade) reveal that 11% of pregnant women seen aborted. The real incidence of abortion we now know is even higher as beta-chorionic gonadotrophin assay reveals that abortion commonly occurs before a missed period¹, and also patients with complete abortions may not be referred to hospital.

Threatened abortion occurs in 16% of pregnancies². Hospital based studies indicate that half these pregnancies will continue though numbers will be influenced by individual admission policy. The earlier the bleeding the greater the risk of loss³, but this is only 9.3% if the fetal heart can be shown on ultrasonography⁴. Comparative studies show that should pregnancy continue to viability there is a higher incidence of pre-term births, small for gestation age babies, retained placentas⁵ and perinatal deaths⁶. Many such studies exclude mothers whose bleeding did not require hospital admission and patients were not always matched with controls. We thought it opportune to compare patients seen in our hospital who had experienced a threatened abortion whose pregnancies continued with matched controls.