If you are in the final stretch of your pregnancy, you may have heard of the Hamilton maneuver , also known as separation of membranes. The SEGO defines it as a “mechanical method to induce labor”, and is performed in consultation by the midwife or gynecologist.
But should the Hamilton maneuver be performed in all cases? Is it an invasive procedure? Is it really effective? With the help of midwife Carla Quintana, founder of the ‘Midwife for me’ project, we know all the details about the Hamilton maneuver, when and why it is indicated , what risks it has and what to expect once it has been performed .
What is and what does the Hamilton maneuver consist of?
The Hamilton maneuver or membrane separation is a simple procedure that consists of separating the membranes in order to increase the activity of endogenous prostaglandins, a hormone responsible for erasing the cervix and promoting labor contractions. This increases the chances that labor will start in the next 48 hours.
It is carried out in consultation through a vaginal examination, putting the index finger in the cervical canal until it touches the amniotic sac, and by means of a circular movement the membranes are separated to detach them from the uterus.
When is it indicated and when is it not?
To begin with, midwife Carla Quintana emphasizes that the Hamilton maneuver should not be performed indiscriminately or protocol to all term pregnant women , since its indication should obey three criteria:
- Since the purpose of this maneuver is to trigger labor , the clinical conditions that justify or make it necessary to end the pregnancy in a reasonably short period of time (but not urgent) must be met. For example, with signs of fetal distress, macrosomic baby, week 41 in the absence of contractions, advanced dilation without clinical signs of the beginning of the first phase of labor …
-
The pregnancy must have reached term, so its practice before the 40th week is not recommended .
-
The maneuver must be performed with a favorable cervix, that is, the cervix is soft.
Regarding its contraindications , as we read in the delivery induction protocol of the Hospital Costa del Sol, of the Health Council of the Junta de Andalucía, the Hamilton maneuver should not be performed when there is a placenta previa or colonization by beta-hemolytic streptococcus group B, gonococcus or chlamydias. It should also not be done if the pregnancy is less than 40 weeks, there is active bleeding and a closed cervix.
Risks of the Hamilton maneuver
Before performing the Hamilton maneuver, it is important to inform the woman of the possible consequences that can be expected, as well as some risks that may arise from this intervention:
-
After its practice, it is likely that contractions will appear that can be increasingly intense and end in labor contractions in the next 24-48 hours (in this post we told you when to go to the hospital if you are in labor). However, the contractions could also relax until they disappear, in which case the maneuver will not have been effective.
-
Although the risk is very small, a ruptured amniotic sac can occur . If the bag breaks and labor does not start after a few hours, it will be necessary to induce it by other means to avoid the risk of infection and other problems.
-
As with vaginal exams, there is also a small risk of infection.
-
Among the most frequent risks is slight bleeding during the 24 hours following the maneuver . It is a completely normal and harmless spot, and unless it increases or does not disappear, it is not necessary to go to the emergency room. The risk of bleeding is very low.
-
It is a rather annoying procedure , as it involves manipulation of the cervical canal. That is why it is important that the woman is relaxed and that the maneuver is carried out when conditions are favorable and the cervix is somewhat erased, so that it allows the entry of a finger without causing pain.
Is it an effective maneuver?
The reality is that there is little up-to-date scientific evidence to recommend or discourage the use of the Hamilton maneuver.
The most recent information can be found in a review published in 2020 in Cochrane, which included 44 randomized studies conducted in almost 7,000 women from a wide range of countries. The aim of this review was to find out if membrane detachment is a safe and effective way to induce labor at term.
The studies compared the evidence of detachment of membranes with the practice of no intervention or a sham intervention, and also with the use of vaginal or intracervical prostaglandins, oral misoprostol and oxytocin.
-
Compared with no-practice women, those who underwent the Hamilton maneuver were more likely to go into labor spontaneously and less likely to have formal induction of labor.
-
But compared to women given vaginal or intracervical prostaglandins, oral misoprostol, and oxytocin, we found insufficient data to draw conclusions.
Therefore, it is concluded that the detachment of membranes can be effective to achieve the spontaneous onset of labor , but the evidence regarding this procedure was of low certainty. It remains to be determined whether there is an optimal number of membrane detachments, as well as the appropriate times and gestational age to facilitate induction of labor.
This is what the WHO says about it
With the data available to date, the Guide on induction of labor published by the World Health Organization (WHO) recommends the Hamilton maneuver or detachment of membranes when there is a non-urgent indication to interrupt the pregnancy , as this practice helps to reduce formal induction of labor.
However, we must take into account the risks that it entails -and that we have mentioned above-, so if compared with expectant management, practicing this maneuver would imply a greater risk of vaginal bleeding, discomfort and even a percentage of possibilities of not going into labor within 48 hours.
Therefore, it is necessary to weigh the possible risks with the expected benefits to make a decision.
It must be done with the consent of the woman
As with any other obstetric procedure, it is essential that before performing this maneuver the woman is informed and her express consent is obtained. But the midwife specifies that “informing is not the same as simply saying ‘I’m going to perform a maneuver to trigger labor, okay?’, Because said like that, any mother is likely to answer yes without having all the information in her hand”
“When, without any reason or justification , the doctor decides to perform a vaginal examination with the Hamilton maneuver on the pregnant woman, and also without informing her of it previously, we are facing a case of obstetric violence”
In this sense, Carla laments that on many occasions the pregnant woman is treated too hastily , forgetting that she is the only protagonist of the whole process and that the baby must be born when she is really ready for it:
“There are health workers who, when faced with a woman’s doubts, answer things like ‘you want to know everything!’ or “you have to trust the professionals who take care of you.” Of course you have to trust, but the woman is the protagonist of her pregnancy and childbirth , she is her vagina and her body, and she has the right to be informed at all times of what what are you going to do to him “
So, if you are in the final stretch of your pregnancy and the doctor or midwife tells you that they are going to perform the Hamilton maneuver, Carla advises that you ask them to inform you in detail, both about their procedure and its consequences, as well as the reason why they recommend you do it. Clarify all the doubts that may arise in this regard, and then make the decision that you consider best in consensus with the professional who attends you.
Photos | iStock
Article written with the advice of | Carla Quintana, ‘Matron for me’
More information | Detachment of membranes for induction of labor – Cochrane, [Journal of the College of Nursing of Cádiz] (College of Nursing of Cádiz)
In Babies and More | When to go to the hospital if you are in labor? Urgent warning signs if you are pregnant or postpartum
