Abruptio Placentae, a Prospective Study

Abstract

Premature rupture of the membranes leading t o p e r i n a t a l death was analyzed i n a p r o s p c r t i v e study of 59,379 pregnancies. 183 cases were placed i n t h e category when the membranes ruptured before 37 weeka g e s t a t i o n o r 20 o r more hours before the onset of labor.The f a t a l d i s o r d e r had a frequency of 3.811000 l i v e b i r t h s . Most of t h e r u p t u r e s appeared secondary t o amniotic f l u i d b a c t e r i a l i n f e c t i o n s . 87% of t h e cases had congenital pneumonia. 71% chorioamnionitia and 59% f u n i s i t i s . The d i s o r d e r decreased a f t e r 27 weeks g e s t a t i o n when a n t i m i c r o b i a l a c t i v i t y appears i n the amniotic f l u i d . I t increased again a f t e r 37 weeka when b a c t e r i a normally gain access t o the amniotic f l u i d i n increased numbers. The l a t e g e s t a t i o n a l peak was comprised almost e n t i r e l y of t h e poor suggesting t h a t antimicrobial a c t i v i t y may have been reduced i n t h e i r amniotic f l u i d s . Gravida who made many c l i n i c v i s i t s had higher weight gains a t each g e s t a t i o n a l age than d i d those who made fewer v i s i t s and those who made many v i s i t s had a very low frequency of t h e f a t a l d i s o r d e r . The disorder was s t r o n g l y a s s o c i a t e d with suboptimal pregnancy weight gain and the r e s u l t a n t neonates had a p a t t e r n of growth retardat i o n c h a r a c t e r i s t i c of undernutrition. There was a 10 f o l d inc r e a s e of the d i s o r d e r with placenta previa and smaller i n c r e a s e s with obesity, hypertension, ambulatory work during pregnancy. p r i o r pregnancies. a b r o t i o n a , f e t a l deaths, preterm d e l i v e r i e s and i n f a n t ' s blood group B.(Supported by U.S.P.H.S. c o n t r a c t N01-NS-2311). Abruptio placentae f a t a l t o t h e f e t u s o r neonate was studied i n a prospective s e r i e s of 59.379 pregnancies with approximately 60,000.000 p i e c e s of d a t a used i n t h e analyses. A l l diagnoses were made by a s i n g l e p a t h o l o g i s t . The f a t a l d i s o r d e r had a f r equency of 4.011000 l i v e b i r t h s . Necrosis of t h e decidua b a s a l i s a t t h e p l a c e n t a l margin. thrombosis of decidual a r t e r i e s and l a r g e p l a c e n t a l i n f a r c t s were t h e most c h a r a c t e r i s t i c p l a c e n t a l abnormalities. The decidual n e c r o s i s was s t r o n g l y c o r r e l a t e d with gravidas' smoking and pregnancy weight gain. There was a p a r a l l e l f e t a l growth r e t a r d a t i o n i n d i c a t i n g t h a t maternal undern u t r i t i o n may have contributed t o t h e abruptions. An increased frequency of decidual n e c r o s i s a t t h e p l a c e n t a l margin was a l s o found i n s u c c e s s f u l , non-abruption pregnancies when t h e gravida smoked and when they had suboptimal pregnancy weight gains. An Richard W. Newcornb and Richard M. Rothberg. University o f Chicago P r i ...