The hazards of vacuum aspiration in late first trimester abortions

Abstract

The incidence of somatic complications in connection with legal termination of pregnancy by vacuum aspiration was analysed in 1,123 hospital patients. Special attention was paid to complication rates in relation to gestational age. It was found that the incidence of major uterine haemorrhage increased with gestational period, being unexpectedly high in the 12th week. When anaesthesia was supplemented with halothane there was a significantly higher incidence of uterine haemorrhage that when this anaesthetic was avoided. The results indicate that strict principles for the operation procedure are mandatory to reduce blood loss and other complications. It is suggested that the end of the 12th week should not be considered as a "magic" time limit for vaccum aspiration but that the policy should aim at early intervention, preferably before the end of the 10th week. In the event of late first trimester abortions or "border line" cases it is of advantage to administer prostaglandin extra-amniotically for pre-operative dilatation of the cervix.

PIP: To determine the rate of complications when vacuum aspiration is related to week of pregnancy and morbidity during the next 2 months, 1123 women in their 6th-15th week of gestation were studied. All of the abortions were done by vacuum aspiration at these periods of gestation from 1967 through 1971 at the Karolinska Hospital (Sweden). Of these, 462 were primigravidas and 661 multigravidas. More than 50% were in the 12th week of pregnancy or later. General anesthesia was used. In 55% of cases halothane was used to supplement other anesthetic agents. Paracervical block was used to aid cervical dilatation. Hegar dilators were then used. Routine check curettage followed vacuum aspiration. Uterine contents and blood loss during the operation were collected and measured. Patients remained in the hospital overnight, or longer if complications occurred. Follow-up examinations were done within the next 2-month period and later when indicated. Uterine perforation occurred in 5 cases (.45%). 4 of these patients were primigravidas. Heavy bleeding increased with gestational age and with use of halothane anesthesia. Halothane anesthesia has been associated with uterine relaxation which favors hemorrhage. Repeat curettage at follow-up examinations was needed in 1.4% of the cases. Early or suspected infections were found in .8-4.5% and late infections in 2.6-5.9%; the overall rate was 7.2%. Physician experience did not seem to be a factor. The high complications rates relate to an unsatisfactory procedure for the periods of gestation, overrepresentation of later terminations, hospital admission for all patients, a long follow-up period, and careful recording of all complications. 75% of the patients were in the 11th week of gestation or later. Abortion in the late stages of the first trimester should not be considered a totally simple and harmless procedure. The rapid mechanical dilatation of the cervix is traumatic. A laminaria tent for slow dilatation produces an increased infection risk. Prostaglandins have recently been used to induce preoperative cervical dilatation. This pretreatment in the late first-trimester abortions has been reported to have reduced uterine hemorrhage from 20% to 3%.