Why does baby engage?
Engagement is one of the first accomplishments of the Cardinal Movements of birth. To engage, baby’s head lowers into the pelvic brim in a way that allows the widest part of baby’s head (parietal eminences) to slip below the pelvic inlet. Engagement is considered to be when 4/5ths of the baby’s head is in the pelvis. The head is no longer ballotable, meaning, the head can no longer be wiggled between the midwife or doctor’s fingers.
Why wouldn’t a baby engage?
Baby’s chin is up, making the head measure longer front to back- An Occiput Posterior baby’s head overlaps the pubic bone (called an unfavorable diameter in the medical text).
- Abundance of amniotic fluid (baby floats too much to engage before contractions help initial descent)
- The head really is too big for the pelvis (rare)
- Severe scoliosis makes the spine curve over the pelvic inlet blocking baby’s path
- Baby is not due yet
- The mother has given birth before and this baby will engage in labor with the help of regular contractions
- The placenta blocks baby’s way, preventing engagement (rare)
- The lower uterine segment has a bit of a twist reducing space for baby
- The pelvic joints are turned making the inlet a narrower shape, not round
The posterior and lack of fetal engagement
Of course, some posterior babies do engage. But posterior position may make engagement less likely. Why wouldn’t a posterior baby be as likely to engage?
The posterior baby may seem to be engaged in the pelvis when the dome of the head is low but the baby may not be engaged if the forehead remains up above the pubic bone. An overlapping head means the head is not engaged, even though this head, too, is not ballotable (bounces in the water when wiggled by the midwife).This drawing shows a mother feeling whether her baby’s forehead rests up on her pubic bone or settles behind it. If you feel the narrow forehead here at the time you are due, it is a clue that baby isn’t actually engaged.
Gail shows the posterior positioned baby resting on the mother’s pubic bone.
When the baby hasn’t engaged at or after the due date, check to see if baby may be in the posterior position. The longer front-to-back length of baby’s head can put the forehead right on mother’s pubic bone. Helping this baby to tuck their chin may help them rotate around and suddenly engage, which can help labor begin on its own when this occurs after 40 weeks gestation or later.
What happens if the baby doesn’t engage before labor?
Labor may start before or after baby engages. Contractions can be the uterus way to engage baby. Strong contractions can occur though the baby remains high in the pelvis.
Before we try to get the cervix to open well, we should use these contractions to help baby turn and down into the pelvis well.
Check baby’s position and assist chin flexion and rotation to the LOT or LOA position if possible. Either tend to be ideal. We have techniques to help in any case.
Some women are recommended to have an induction, even if their baby is not engaged. It may be possible to avoid or ease an induction by increasing balance of the maternal structures before engaging or early in the induction process (or the days before), by helping baby
Tuck their chin to their chest (flexed head), if needed Turn out of the posterior position, if possible.
If baby isn’t posterior and previous labors have gone well, labor contractions will most likely engage baby without more than some smart birth positions.
If baby is posterior and previous labors have gone well, contractions will also most likely turn and then engage this baby.
On the other hand, if labor isn’t starting, do the balance activities discussed in the daily and weekly activities in this part of the website. A mother who had to have her first baby by cesarean because baby didn’t engage (remained high) may be more likely to have a natural birth if her next baby engages, I’ve noticed. There are several positions and techniques to help a baby engage with uterine contractions.
Techniques to help a baby engage
Doing several techniques increases success. Don’t expect to do only one and be done. Increase success by getting bodywork (a chiropractor can help align her pelvis and do the Webster Maneuver) and do your own activities daily at the end of pregnancy. Techniques to help baby engage will help open the brim, tuck the chin and rotate the baby to a left-sided presentation:
- Align the pelvic brim (Chiropractic, Osteopathic, and somewhat with the Forward-leaning Inversion)
- Align the sacrum which may be torqued on a vertical axis and distorting the lower uterine segment (Standing Sacral Release)
- Relax the spasm out of the cervical ligaments (aka uterosacral or posterior ligaments, woman may have a history of retroverted cervix with Forward-leaning Inversion)
- Relax the psoas muscle pair (resolve chronic muscle tension in the illiopsoas with psoas stretch such as a forward lunge gently and frequently done through the day)
- Help baby tuck the chin, aka; flex the head (with 10 Abdominal Lift and Tuck during contractions)
- Help baby rotate to left occiput transverse (lateral), left occiput anterior, or occiput anterior (Dip the Hip, Side-lying Release, Forward-leaning Inversion through 1-3 contractions, 1-3x)
- Walk briskly with free-swinging thighs.
- Sit on a firm birth ball and make sweeping circles with the hips. Doing a figure-8 shape to your swing helps, especially after doing the Side-lying Release or Dip the Hip.
- Use engaging activities once labor begins and contractions are predictable (posterior pelvic tilt, Abdominal Lift).
Sometimes a bodyworker is best for a particular situation. Sometimes, even with balancing, labor surges are necessary to rotate and engage baby.
“I’m working with a woman who is about to be induced and her baby is at -2 station, should I suggest Walcher’s?”
Walcher’s position is only effective with contractions. Don’t recommend it in pregnancy.
Then what shall I do?
Begin instead with Balance. This is why Balance is the first principle before Gravity and Movement. Balance in this case means activities to help the mother’s anatomy be more symmetrical and supple on both sides as concerns tension and relaxation (or tone) of the muscles, ligaments, and alignment of the pelvic bones.
Psoas release helps you have a long, supple psoas muscle pair. See our Daily Activities, free on this site.
Once there are regular contractions, whether spontaneous or by induction, the Abdominal Lift and Tuck through 10 contractions may do the trick of lowering the baby into the pelvis, and if not, Walcher’s during and between 3 contractions (and between because its so uncomfortable she won’t likely go back to it a second time). Walcher’s is intense, and so is for when other ways of getting baby to engage don’t work. Be patient and keep moving in ways that open the pelvic brim. Some positions are comforting but they hold baby up.
While baby remains high avoid laboring in a:
- Squat
- Child’s pose
- Knee chest (see why this is not Open-knee chest.)
Don’t panic! Balance your body instead!
Before the birth:
I’m 39+1 weeks pregnant and still trying to get the baby’s head engaged. It’s currently only 1/5 in the pelvis. Open to any suggestions. I’ve been doing pre-natal yoga all of my pregnancy. And have been doing your Daily Essentials for months. I walk or ride most days. And have been seeing a osteopath regularly.
And after the birth:
Being my first pregnancy I was very surprised that my labour was only two hours. I had done the Daily Essentials and prenatal yoga most of my pregnancy, and believe that this aided in my perfect birth and our baby being in the most perfect position to birth so easily.
Conclusion
Babies naturally engage in the pelvis when the body is balanced and the brim open enough. Fetal chin tucking and coming down from the mother’s left side helps more babies fit the top of the pelvis.
Generally, we hope for flexion and rotation before engagement. This is most important when we find baby in the posterior position and high after 38-39 weeks pregnancy when pregnant with a first child, or going for a vaginal birth after a previous cesarean.
Work on Balance before working on rotation and descent. Sometimes we have a time issue, as when the amniotic membranes have released and when a provider has a time limit for labor. Descent from a non-optimal position may have additional challenges that may be met with balance, birth positioning and other activities in labor.
Fetal engagement may help the onset of labor be more spontaneous. Once in labor, check out information and techniques to help the baby engage.
References on fetal engagement topics
Ghi, T., et al. “Sonographic pattern of fetal head descent: relationship with duration of active second stage of labor and occiput position at delivery.” Ultrasound in Obstetrics & Gynecology 44.1 (2014): 82-89. (13.5% of babies were posterior with a 50% cesarean rate. Posterior babies came down through the pelvis better if flexed as told by observed Angle of Progression.)
Haberman, S., et al. “OP22. 08: To evaluate the value of the determination of occipito posterior position before head engagement and risk of persistent OP and Cesarean section.” Ultrasound in Obstetrics & Gynecology 38.S1 (2011): 121-121. (Before engagement, 76 (43%) fetuses were in occiput posterior position (OP), but 67 (88%) of them rotated to occiput anterior (OA) during labour. Eleven (6%) fetuses were delivered in OP, and 9 of them were in OP before engagement (P < 0.001). 22.4% of cases in the OP group underwent Cesarean section compared to 12.7% of controls (P < 0.001).
Khurshid, Nadia, and Farhan Sadiq. Management of Primigravida with Unengaged Head at Term Placenta 4.2 (2012): 4. (The incidence of high head in primigravidas at term was 22%.The most common cause was deflexed head, next was cephalopelvic disproportion. In 40% no cause found. Vaginal delivery occurred in 67% of cases, 33% of cases had caesarean section. No interference i.e., ventouse or forceps required in 60% of cases. In 64% cases labour lasted more than 12 hrs.)
Shaikh, Farhana, Shabnam Shaikh, and Najma Shaikh. “Outcome of primigravida with high head at term.” JPMA. The Journal of the Pakistan Medical Association 64.9 (2014): 1012-1014. (The most common identified cause of non-engaged head was deflexed head in 28(28%), while no cause was found in 45(45%) women. Further, 45(45%) women presented with spontaneous labour, while labour had to be induced with prostaglandin in the rest. Vaginal delivery occurred in 59(59%) cases and caesarean section was performed in 41(41%).
Verhoeven, Corine JM, et al. “Does ultrasonographic foetal head position prior to induction of labour predict the outcome of delivery?.” European Journal of Obstetrics & Gynecology and Reprod Biology (2012).
Roshanfekr, Daniel, et al. “Station at onset of active labor in nulliparous patients and risk of cesarean delivery.” Obstetrics & Gynecology 93.3 (1999): 329-331.iology (2012).
Best outcomes for first time mothers with unengaged babies were found in this 1999 study: Roshanfekr, Daniel, et al. “Station at onset of active labor in nulliparous patients and risk of cesarean delivery.” Obstetrics & Gynecology 93.3 (1999): 329-331.