Use of intra-amniotic urea as a second trimester abortifacientAsha Khare, Malini A Deshmukh, Pratibha R Vaidya, Asif Sayed, Rashida T Companywalla, Nergish D Motashaw
Department of Obstetrics and Gynaecology, K.E.M. Hospital and Seth (G.S. Medical College, Parel, Bombay-400012, India
Correspondence Address: Source of Support: None, Conflict of Interest: None PMID: 529168
Source of Support: None, Conflict of Interest: None
Seventy cases of mid-trimester pregnancies were terminated by using 200 ml. of 40% intra-amniotic urea, over a 13 month period from 1st August. 1977 to 31st August, 1978.
No ideal method has yet been found to procure safe and effective midtrimester abortion. Various drugs, their combinations and varying dose schedules of drugs have been used from time to time to evaluate their efficacy and safety.
The criteria by which an abortifacient is judged are as follows:
2. Side effects and complications.
3. The induction-abortion interval.
4. Rate of incomplete abortion.
Intra-amniotic instillation of hypertonic saline with or without oxytocin is commonly used for terminating midtrimester pregnancy. " Since this can sometimes lead to a fatal complication in the form of intravascular coagulopathy, .,. search is being continued for a safer alternative.
Interest has recently arisen over the use of intra-amniotic urea for the same purpose. The mode of action of urea is similar to that of hypertonic saline. There is a decrease in the circulating progesterone level and an increase in prostaglandin release.  It also causes foetal death which may account for part of its action. Urea is a physiological substance and one of the main advantages include the lack of significant complications with inadvertent intravenous infusion of urea. 
Seventy cases of midtrimester pregnancies were terminated by injection of 200 ml. of urea (40%) intra-amniotically between the period August 77 to August, 1978.
Selection of patients
Patients with a gestational period of 16-20 weeks were selected for this procedure.
Routine vaginal and abdominal examinations were carried out prior to the procedure to confirm pregnancy and determine its duration.
Routine investigations such as Hb, Blood group, Rh factor and urine examinations were also carried out.
An injection of 0.6 mg atropine, intramuscularly, was given half an hour before the procedure.
The patient was asked to pass urine and then made to lie down in a supine position on the operation theatre bed. Amniocentesis was then done. The stillete was removed and a free flow of amniotic fluid obtained.
Freshly prepared 200 ml of 40% urea in distilled water was then instilled by the running drip method. The patients were observed in the ward round the clock.
After twenty four hours the patient was put on a course of intravenous pitocin diluted in 500 ml of 5% glucose. The bottles contained 20, 25 and 30 units of pitocin respectively.
Out of a total of 70 women there were 32 patients belonging to the age group of 20 years and less. There were only 6 cases above the age of 30 years [Table 1].
[Table 2] shows that there is no relation between the induction-abortion interval and the gestation period; only 8 failures were encountered. The success rate was 88.7% .The average induction abortion interval was 30.7 hours. The maximum abortions occurred between 24-48 hours. 13%, of the cases aborted within 24 hours, 57% within 36 hours and 90% within 48 hours, 8 cases who failed to abort within 72 hours were subjected to another method of medical termination of pregnancy (MTP).
Urea is being used intravenously in sickle cell crisis for alleviation of pain and prolongation of cell survival time without any notable side effects.  It is also given by the same route for neurosurgical procedures in the dose of 1-1.5 gms/kg of body weight. 
Intramural injection of urea does not cause muscle necrosis  which occurs with hypertonic saline. Since the concentration of urea also causes immediate foetal death the problem of delivering alive foetus is not encountered. The psychological trauma to the mother is thus avoided. Urea is used alone or in combination with various drugs for the purpose of mid-trimester abortion. [Table 3] gives the induction abortion interval for urea and saline in different series. whom curettage was done. There were two cases of pelvic infection who were treated conservatively.
Burnett et al  in their series of seventy four patients who had their pregnancies terminated by a combination of intra-amniotic urea and intra-venous oxytocin noted the following biochemical changes. Maximum changes in serum electrolyte level occurred 8-12-hours after the injection and included a decrease in the mean concentration of NaCl and CO 2 , and an increase in serum potassium. An increase in urinary urea began within four hours. There was a decrease in serum fibrinogen level by about 15% and also an 18-20% drop in the platelet count 8 hours after the procedure. Fibrinogenfibrin degradation products were significantly increased in 36 patients with minimal side effects a larger series of 1,000 cases or more is required for assessing its safety. Augmenting agents in the form of a pitocin drip or prostaglandins may be used to ensure predictably short induction-abortion interval to minimise the risk of endometritis or salpingitis which may be associated with a prolonged induction abortion interval.
We thank Dr. C. K. Deshpande, Dean, K.E.M. Hospital and Dr. V. N. Purandare, Head, Dept. of Obst. & Gynaec., for allowing us to use the hospital data. We also thank the Dept. of Pharmacology, K.E.M. Hospital for their continued co-operation in supplying the requisite urea solution.[Table 4] 
[Table 1], [Table 2], [Table 3], [Table 4]