At 40 weeks, you’re at your due date, and wanting labor to start is completely reasonable. Your options range from simple physical techniques you can try at home to medical procedures your provider can perform in the office or hospital. Some methods have solid evidence behind them, while others are more theoretical. Here’s what actually works, what might help, and what to expect from each approach.
What Your Provider Checks First
Before any induction method, medical or otherwise, your provider will likely assess how ready your cervix is for labor. This is done using a scoring system based on five factors: how dilated your cervix is, how thin it’s become, how soft it feels, its position, and how far your baby’s head has descended into the pelvis. A score of 6 or 7 out of 13 generally signals that your body is primed for labor and induction is more likely to succeed without increasing the chance of a cesarean. A lower score means your cervix may need help ripening before contractions can do their job effectively.
Membrane Sweeping: The In-Between Option
A membrane sweep is one of the most common first steps. Your provider inserts a finger through your cervix and separates the amniotic sac from the uterine wall using a circular motion. This releases natural hormones that can trigger contractions. It’s done in a regular office visit, takes about a minute, and doesn’t require any medication.
About 50% of women go into labor within seven days of a sweep. That’s a meaningful number, though it also means it doesn’t work for everyone. Common side effects include cramping, irregular contractions, and light spotting afterward. These are normal and expected. A sweep can be repeated at a follow-up visit if the first one doesn’t get things going.
Hospital Induction Methods
If your provider recommends a formal induction, several tools are available depending on your cervix’s readiness.
Cervical Ripening
When your cervix hasn’t softened or dilated enough on its own, ripening agents help prepare it. One common mechanical option is a small balloon catheter inserted through the cervix. It applies gentle, steady pressure that encourages dilation, typically to about 3 centimeters, at which point it falls out on its own. Hormonal options in the form of vaginal or oral medications can also soften and thin the cervix over several hours. Your provider chooses between these based on your specific situation, including whether you’ve had a prior cesarean.
Breaking the Water
An amniotomy, where your provider makes a small opening in the amniotic sac with a specialized tool, can be done once your cervix is dilated and your baby’s head is well engaged in the pelvis. If contractions haven’t started yet, breaking the water can initiate them. If they’re already underway, it typically makes them stronger and more frequent. Most women go into active labor within a few hours of an amniotomy, though sometimes additional support with synthetic oxytocin is needed.
Synthetic Oxytocin
This medication is given through an IV to start or strengthen contractions. The dose is increased gradually until contractions are coming regularly and with enough intensity to progress labor. Throughout the process, your contractions and your baby’s heart rate are monitored continuously. If the baby shows signs of stress, the medication can be reduced or stopped quickly, which is one of its advantages over other methods.
What the Evidence Says About Elective Induction
If you’re healthy, carrying one baby, and this is your first full-term pregnancy, elective induction at 39 to 40 weeks is a well-supported option. Research has shown that healthy first-time mothers induced at 39 weeks actually had lower rates of cesarean delivery compared to those who waited for labor to start on its own. They also had lower rates of developing dangerously high blood pressure during the final weeks. ACOG now includes elective induction at 39 weeks as a reasonable choice for women who meet these criteria, though it remains a personal decision you make with your provider.
Physical Techniques You Can Try at Home
None of these are guaranteed to start labor, but they carry minimal risk and may help your baby settle deeper into your pelvis, which puts more pressure on your cervix and can encourage dilation.
Walking is the simplest option, and a specific variation called curb walking may offer additional benefit. You place one foot on a curb and the other on the street, then walk forward. The uneven surface creates an asymmetrical movement in your pelvis that may encourage your baby’s head to descend further. Regular walking, squats, lunges, and pelvic tilts all promote pelvic flexibility in the final weeks of pregnancy.
Sitting and bouncing on a birthing ball, or doing slow hip circles on one, can also encourage your baby to move downward and may reduce pelvic tension. These exercises are gentle enough to do for extended periods throughout the day.
Nipple Stimulation
This is one of the few natural methods with a physiological basis that’s been studied in clinical settings. Stimulating the nipples triggers your body to release oxytocin, the same hormone that drives contractions. In research trials, women were asked to stimulate using a breast pump or by hand for periods of at least 30 minutes, with breaks of up to 15 minutes as needed, aiming for a cumulative total of at least 2 hours. This isn’t a casual technique. It requires commitment, and contractions should be monitored because overstimulation is possible.
Castor Oil: Proceed With Caution
Castor oil is a powerful laxative, and the intense intestinal cramping it causes can sometimes trigger uterine contractions. The studied dose is two ounces taken by mouth one time only. However, most providers don’t recommend it because nausea is a significant and common side effect, and the last thing you want heading into labor is to be dehydrated and exhausted from hours of diarrhea and vomiting.
Castor oil should not be used before 40 weeks, and it’s not appropriate if you’ve had a prior cesarean. If you’re considering it, talk to your provider first. The discomfort-to-benefit ratio is poor compared to other options.
What Doesn’t Have Strong Evidence
Spicy food, pineapple, dates, evening primrose oil, and sex are all commonly suggested. Spicy food and pineapple have no meaningful evidence supporting them. Sex has a theoretical basis (semen contains natural prostaglandins, and orgasm can cause uterine contractions), but clinical studies haven’t shown it reliably induces labor. Eating dates in the final weeks of pregnancy has some small studies suggesting it may improve cervical readiness, but the evidence isn’t strong enough to count on. None of these are harmful at 40 weeks, but treating them as reliable induction methods will likely lead to disappointment.