Risk factors for the recurrence of premature rupture of the membranes

Premature rupture of the amniotic membranes (FROM) occurs in up to 20% of all births. Although many studies have examined risk factors for FROM and, in particular, preterm FROM (PPROM, if less than 37 weeks' gestation), the aetiology of FROM recurrence has not been examined as closely. This study investigated factors that may increase the risk of FROM among women who have already experienced one FROM birth. Maternally linked Washington State birth certificates from 1984 to 1993 identified 208 women with consecutive FROM births. Controls were a random sample (n = 848) of women who had one birth on record complicated by FROM, but whose subsequent birth was not. Among women with a prior term FROM, increased risk for FROM recurrence (term FROM or PPROM) was associated with an intervening fetal death at less than 20 weeks' gestation (OR = 2.4, 1.3-4.5) and with parity of two or more (OR = 2.0, 1.3-3.4). None of the factors assessed significantly increased the risk of recurrence of FROM (term FROM or PPROM) among women with a prior PPROM. Other potential risk factors for FROM recurrence were evaluated within the two FROM groups (PPROM or term FROM at first birth) by stratifying among the cases according to gestational length at subsequent birth.