Inducing labor can help start the birthing process when a pregnancy has extended past its due date or if there are medical concerns that make carrying the pregnancy longer risky. While inducing labor has risks, the methods used to induce have become much safer in recent years as doctors better understand how to mimic the natural onset of labor. When weighing the risks and benefits of induction, the safety of the method used is an important consideration.
When is induction recommended?
There are several situations where a doctor may recommend inducing labor:
- The pregnancy has reached 41-42 weeks and labor has not started naturally. After 42 weeks the placenta may not function as well, putting the baby at higher risk.
- The fluid around the baby (amniotic fluid) is low or leaking early. This can increase chances of infection.
- The mother has a medical condition such as diabetes, high blood pressure, kidney disease or autoimmune disease that makes continuing the pregnancy risky.
- Tests show the placenta is not functioning properly.
- The baby is not growing well in the womb.
- There are signs of fetal distress.
In these situations, the risks of waiting for labor to start naturally may outweigh the risks of inducing labor. The timing and method of induction should be carefully chosen to promote safety.
Methods of induction
There are several options doctors may use to induce labor. The different methods can be divided into mechanical and pharmacological methods:
Mechanical methods
- Stripping/sweeping the membranes: The doctor massages the thin membranes connecting the amniotic sac to the cervix and wall of the uterus. This releases prostaglandins which can encourage contractions and cervical ripening.
- Inserting a Foley catheter: A Foley catheter with a small balloon on the end is inserted through the cervix and inflated. This puts pressure on the cervix which releases prostaglandins to encourage ripening and dilation.
- Rupturing the amniotic sac (breaking the waters): Using a thin instrument, the doctor makes a hole in the amniotic sac releasing the amniotic fluid. This removes the cushioning effect of the fluid which often triggers contractions.
- Nipple stimulation: Stimulating the nipples releases oxytocin which can cause uterine contractions. This is usually done by hand or with a breast pump.
Pharmacological methods
- Prostaglandin medications: Prostaglandins applied as a gel, insert or tablet help ripen and dilate the cervix. Examples are Cervidil and Cytotec.
- Oxytocin/Pitocin: This is a synthetic version of the hormone oxytocin given through an IV. It stimulates contractions.
- Misoprostol: This prostaglandin tablet is sometimes used in combination with other induction methods.
Safety considerations with different induction techniques
When determining the safest method for an individual patient, doctors consider the following risks and benefits of each option:
Membrane stripping
- Benefits: Non-pharmacological, mimics natural process, low risk
- Risks: Infection if done too early before cervix is partially dilated
Foley catheter
- Benefits: Mimics natural dilation, mechanical so fewer drug interactions
- Risks: Infection, dilation may still take time
Breaking the waters
- Benefits: Often kickstarts labor quickly
- Risks: Cord prolapse if not engaged, increased infection risk once protective waters gone
Nipple stimulation
- Benefits: Natural release of oxytocin, non-pharmacological
- Risks: Takes consistent stimulation, oxytocin can cause too-strong contractions
Prostaglandins
- Benefits: Effective for ripening cervix, can be removed if over-stimulation occurs
- Risks: Can cause strong contractions, chance of uterine rupture if high doses are given
Oxytocin
- Benefits: Closely mimics natural oxytocin release, can be adjusted
- Risks: Oversensitivity can cause excessively strong contractions, fluid overload
Misoprostol
- Benefits: Inexpensive, easy to use
- Risks: Cannot be removed once given, higher incidence of uterine rupture
Overall, mechanical methods are safer as they work with the body’s natural processes. Pharmacological methods can be helpful but require close monitoring as they are powerful drugs with risks if misused.
Guidelines for safe induction
To promote a safe induction, the following guidelines are recommended by major medical organizations:
- Gestational age should be accurately determined to avoid early induction risk.
- Bishop score should be 6 or more to show cervical readiness.
- Start with mechanical methods and gentle ripening agents first.
- Use lowest effective dose of medications.
- Closely monitor baby and contractions for signs of distress.
- Avoid strong medications if prior uterine surgery.
- Have anesthesia and emergency resources available.
- Ensure guardrails in place to prevent excess stimulation.
Adhering to safe induction protocols minimizes the risks of problems like uterine rupture, fetal distress and complications from strong contractions.
How to choose the safest induction method
The safest induction method can vary based on individual factors. Here are some considerations in choosing the optimal technique:
| Factor | Safer options |
|---|---|
| Bishop score/cervical ripening | Sweeping membranes, Foley catheter, prostaglandin inserts |
| Need for rapid stimulation | Breaking waters, oxytocin |
| History of uterine surgery | Mechanical methods, gentle prostaglandins |
| Fetal positioning not vertex | Avoid breaking waters due to cord prolapse risk |
| Labor stalls after water breaks | Oxytocin augmentation |
| No epidural planned | Avoid excess oxytocin due to pain |
An unfavorable cervix or need for gradual ripening may indicate starting with mechanical techniques like Foley bulb and stripping membranes. If stimulation is urgently needed, amniotomy and oxytocin may be preferred for rapid onset. With an unengaged baby, avoiding breaking the waters reduces cord prolapse risk.
For each patient, the doctor will determine the ideal method based on the clinical situation while following evidence-based safety protocols. This thoughtful approach promotes the best outcome for mom and baby.
Conclusion
While no induction method is completely without risks, following safety guidelines and choosing options suited to each patient’s needs promotes a successful, lower-risk labor induction. Mechanical techniques like membrane stripping and Foley catheters gradual mimic natural dilation while minimizing medication exposure. Pharmacological methods can provide powerful stimulation under careful monitoring. Exploring the benefits and risks of each approach allows doctors to guide patients through a safe, effective induction resulting in the vaginal delivery of a healthy newborn.