Oxytocin for abortion

Secreted by the hypothalamus and stored in the axons of the posterior pituitary gland, the neurohormone oxytocin began to be used to terminate pregnancy in the second half of the last century - after it was synthesized chemically. Although it was known much earlier as a stimulator of labor, playing a central role in regulating labor.

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Instructions for oxytocin for termination of pregnancy

The official instructions for oxytocin for terminating pregnancy apparently did not provide a suitable formulation, so they limited themselves to the phrase that the drug can be used to carry out artificial, medically induced premature labor - a method of terminating an unsuccessful or complicated pregnancy at a later stage (after the 20th week).

Oxytocin is used in obstetrics and gynecology as a uterotonic agent to stimulate prolonged labor; reduce bleeding after delivery in cases of myometrial hypotonia; activate the removal of postpartum discharge (lochia) and residues from the uterine cavity after a miscarriage; to improve uterine muscle contractions (involution) after natural childbirth and cesarean section. It is also used after gynecological operations to stop uterine bleeding.

Oxytocin is produced under various trade names (Syntocinon, Syntocin, Sinpatin, Ipofamin, Orastin, Pitocin, Utedrin, etc.), and all of them are produced in the form of a solution for parenteral use, since this substance is destroyed in the gastrointestinal tract. Therefore, it must be administered by injection.

Enzyme-resistant, i.e. stabilized oxytocin in tablets for termination of pregnancy is represented by the analogue drug Desaminooxytocin (synonyms Demoxytocin and Sandopart). It is used transbuccally: the tablet is held in the cheek until it completely dissolves.

Using Oxytocin to Terminate a Pregnancy: How It Works

The use of oxytocin for termination of pregnancy is permissible at terms up to 4-5 obstetric weeks – up to the middle of the embryonic period. In conditions of a normally developing pregnancy, by the end of the term, under the influence of estrogen, not only the content of oxytocin in the blood plasma increases, but also the number of its receptors in the muscle tissue of the uterus, because in pregnant women it is synthesized in the ovaries, and in the uterus, and even in the fetal membranes. The stimulating effect of this neurohormone on the smooth muscles of the uterus leads to the onset of labor, and it also ensures contractions throughout the entire process of childbirth.

The biochemical mechanism of synthetic oxytocin administered in early pregnancy is based on its natural stimulating effect on specific receptors of contractile proteins actomyosin in the muscles of the uterine lining, primarily by increasing the release of intracellular calcium ions, which “turn on” the contractile apparatus of the myometrial muscle cells.

Intravenous injections of oxytocin for termination of pregnancy cause an immediate response of the uterus, the contractions of which subside after 1-1.5 hours. After intramuscular injection, the muscles of the uterus begin to contract after 5 minutes, with a gradual weakening and fading of contractions over 2-3 hours. Medical abortion is performed only in a medical institution and only under the supervision of doctors, who must make sure that the pregnancy is terminated (that is, the fertilized egg has completely left the uterine cavity). Naturally, the dosage of oxytocin for termination of pregnancy is determined by the doctor, since the frequency of uterine contractions and their duration depend on the dose.

It should be borne in mind that oxytocin has side effects in the form of increased heart rate, increased or decreased blood pressure, nausea and vomiting, cerebrovascular accidents (including hemorrhage), bronchospasm and anaphylactic shock.

For women with uterine developmental abnormalities, fibroids, scars on the cervix (after surgery), ectopic pregnancy, as well as dysfunction of the adrenal cortex, medical termination of pregnancy, including with the help of oxytocin, is contraindicated.

To date, there are practically no reviews of oxytocin for termination of pregnancy, since in recent years in obstetrics and gynecology, tablet preparations based on prostaglandins E2 or F2α, endogenous biologically active substances responsible for uterine contraction, have been used for this purpose.

The price of oxytocin for termination of pregnancy depends on the manufacturer and ranges from 13-15 UAH for a domestic drug to 50 UAH and higher for an imported one.