Chronic effects of maternal smoking on pulse waves in the fetal aorta.

Objective: In order to evaluate the impact of maternal smoking on arterial stiffness in utero, pulse wave characteristics in the fetal aorta were investigated. A prospective clinical study was made of 34 smoking and 34 non-smoking healthy volunteers with uncomplicated pregnancies at 31-40 weeks of gestation.

Methods: The mechanical properties of the fetal thoracic aorta were assessed by an ultrasonic phase-locking echo-tracking system.

Maternal smoking and causes of very preterm birth.

Background: Smoking increases the risk of preterm birth. The present study was made to elucidate the relation of smoking to causes of very preterm birth.

Methods: In a case-control study on all very preterm births in two regions of Stockholm 1988-1992, prospectively collected data were extracted from antenatal and delivery records on smoking, other maternal characteristics, pregnancy complications, and causes of preterm birth.

Placental abruption and perinatal death.

Studies of risk factors for abruptio placentae (AP) are partly conflicting and studies of risk factors for perinatal death in these pregnancies are scarce. Using the population-based Swedish Birth Registry from 1987 to 1993, we were able to study these risks in 795,459 singleton pregnancies. Logistic regression analysis was used to estimate odds ratios (OR) for risk of AP and risk of perinatal death in pregnancies with and without AP.

Preterm birth and maternal smoking: risks related to gestational age and onset of delivery.

Objective: The object was to examine the effects of smoking on spontaneous and induced very and moderately preterm birth (< or = 32 and 33-36 completed weeks' gestation, respectively).

Study Design: Live singleton births in Sweden, 1991-1993 (n = 311,977), were examined.

Results: Risk of preterm birth consistently increased with amount smoked.