“Hip dysplasia after childbirth” actually describes two related but distinct situations: a mother whose own hip dysplasia becomes symptomatic or worsens during and after pregnancy, and a baby who is diagnosed with developmental dysplasia of the hip (DDH) shortly after being born. Both are genuinely connected to the childbirth process, though through different mechanisms. The maternal version tends to involve hormonal and biomechanical stresses that unmask or accelerate a pre-existing hip problem, while the infant version is a separate developmental condition shaped by genetics, fetal positioning, and even how the baby is handled after delivery.
When Pregnancy Unmasks a Mother’s Hip Dysplasia
Many women go through their teens and twenties with mild hip dysplasia and never know it. The hip socket may be slightly shallow, but muscles, ligaments, and the labrum (a ring of cartilage lining the socket) compensate well enough that nothing hurts. Pregnancy changes that equation. Hormones like relaxin and progesterone loosen ligaments throughout the pelvis to prepare for delivery, and the compensatory structures that were quietly holding the hip together can lose their tension. Add to that the weight gain and altered posture of pregnancy, and a hip that was borderline stable can start producing pain, clicking, or a sense of giving way.
This does not mean pregnancy causes hip dysplasia in an otherwise normal joint. The underlying anatomy was already there. What pregnancy does is remove the margin of safety that kept the condition silent. Postpartum, some women find that symptoms improve as hormone levels normalize and ligaments tighten again over the following months. Others discover that things have shifted enough to keep hurting.
Why a Dysplastic Hip Can Get Worse During and After Pregnancy
For women who already know they have hip dysplasia, pregnancy carries a specific concern: accelerated cartilage damage. The combination of increased joint laxity, greater body weight, and months of altered gait mechanics can push a borderline hip toward osteoarthritis faster than it would have gone otherwise. A case report in the orthopedic literature documented a woman who had undergone hip arthroscopy for a related condition years earlier and then experienced progressive osteoarthritis during a subsequent pregnancy. The authors concluded that the hormonal changes leading to increased ligamentous laxity may put vulnerable patients with hip dysplasia at heightened risk for arthritis progression.1Journal of Orthopaedics. Progressive osteoarthritis during pregnancy several years following hip arthroscopy for femoroacetabular impingement
Labral tears are another postpartum finding that can overlap with dysplasia. A systematic review of intra-articular soft tissue problems in postpartum hips found that labral pathology was the most common finding, with the majority of affected patients eventually needing arthroscopic surgery for labral repair or debridement. The authors noted that intra-articular soft tissue injury is a documented but still under-recognized cause of pregnancy-related hip pain.2Current Reviews in Musculoskeletal Medicine. Intra-articular Soft Tissue Pathology of the Postpartum Hip: A Systematic Review If you have lingering deep hip pain after delivery that does not resolve in the usual postpartum recovery window, a labral tear or worsening dysplasia is worth discussing with an orthopedic specialist rather than assuming it is just “normal” postpartum aches.
Delivering With Known Hip Dysplasia
One of the first questions women with diagnosed hip dysplasia ask their obstetricians is whether they can deliver vaginally. The research here is reassuring. A review of the current evidence found that hip dysplasia is not associated with high-risk complications during pregnancy or with increased difficulty in vaginal delivery.3PubMed Central. Current Evidence about Developmental Dysplasia of the Hip in Pregnancy The dysplastic hip itself does not typically prevent normal labor.
The picture shifts, however, for women who have had corrective surgery before becoming pregnant. Periacetabular osteotomy (PAO) is the most common bone-reshaping procedure for adult hip dysplasia, and a systematic review of pregnancy outcomes after PAO found that about 37% of patients in the studies delivered by cesarean section, well above the European average. In half of those cases, the physician recommended the C-section solely because of the patient’s surgical history, not because of any complication during labor.4Journal of Hip Preservation Surgery. Sexual function and pregnancy outcomes after periacetabular osteotomy: a systematic review Reassuringly, the review found no difference in rates of preterm delivery, birth weight, or complications between post-PAO mothers and the general population. So the higher C-section rate seems to reflect physician caution more than genuine obstetric need.
Developmental Dysplasia of the Hip in Your Newborn
The other meaning of “hip dysplasia after childbirth” is the one pediatricians screen for in the first days and weeks of life. Developmental dysplasia of the hip in infants is a spectrum ranging from a mildly loose hip socket to a fully dislocated joint. It affects roughly 1 to 3 percent of newborns to some degree, with girls affected far more often than boys.
Breech presentation is one of the strongest risk factors. An ultrasound study of over 400 breech-delivered newborns found that about 6% had neonatal hip instability, with first-borns, babies in breech position with extended knees, and high-birthweight infants at the highest risk.5PubMed. Ultrasonographic evaluation of breech presentation as a risk factor for hip dysplasia The extended-knee position appears to put sustained pressure on the developing hip socket during the final weeks in the womb, when the joint is still soft and malleable.
Does the Way a Baby Is Delivered Matter?
For babies in the head-down position, the mode of delivery does not appear to significantly influence hip stability. But for breech babies, the data tells a different story. A study of nearly 1,000 term singleton breech births found DDH rates of about 3.7% after elective (pre-labor) cesarean section, compared to roughly 8% after vaginal delivery.6PubMed. Elective Caesarean section is associated with a reduction in developmental dysplasia of the hip in term breech infants The difference was statistically significant and suggests that the mechanical forces of labor and vaginal delivery can destabilize an already-vulnerable hip.
A follow-up prospective study refined this further. When researchers excluded the mildest form of dysplasia (which may just represent normal immaturity), the rate of clinically relevant hip dysplasia was roughly 4.7% in vaginally delivered breech babies versus about 1.1% in the elective cesarean group.7PubMed. The relationship between mode of delivery and developmental dysplasia of the hip in breech infants: a four-year prospective cohort study That does not mean every breech baby should be delivered by C-section to protect the hips; the decision involves many other factors. But it does mean breech-delivered infants warrant careful hip monitoring regardless of how they were born.
The Genetic Thread Between Maternal and Infant Hip Dysplasia
If you had hip dysplasia yourself and your baby is now diagnosed with DDH, the connection is not coincidental. Hip dysplasia runs strongly in families. A large population-based study found that first-degree relatives of someone with DDH had a relative risk about 12 times higher than the general population. Even first cousins showed a modestly elevated risk. The researchers identified hundreds of families with five or more affected individuals, confirming a strong hereditary pattern.8PubMed. Familial predisposition to developmental dysplasia of the hip
The genetics are not simple, though. DDH does not follow a single-gene, predictable inheritance pattern in most cases. It behaves as a complex trait, meaning multiple genes interact with environmental factors like fetal positioning and hormonal exposure. One research effort using a large four-generation family with many affected members did identify a specific shared genetic variant in a gene called CX3CR1, located on chromosome 3, that was co-inherited by all affected family members.9Journal of Bone and Mineral Research. Developmental Dysplasia of the Hip: Linkage Mapping and Whole Exome Sequencing Identify a Shared Variant in CX3CR1 in All Affected Members of a Large Multigeneration Family Findings like this are promising for understanding the biology, but no genetic test currently exists that can predict DDH in a newborn. Family history remains the most useful genetic signal clinicians have.
Relaxin Receptors and Why Girls Are More Affected
The hormone relaxin, which loosens the mother’s pelvic ligaments during pregnancy, also circulates in the fetus. Female infants appear more responsive to it. Researchers comparing hip tissue from female infants with DDH to tissue from unaffected infants found that the DDH group had dramatically higher concentrations of relaxin receptors in the ligamentum teres, a small ligament inside the hip joint. The receptor density in the DDH group was roughly four times higher than in controls.10PubMed Central. Greater presence of receptors for relaxin in the ligamentum teres of female infants who undergo open reduction for developmental dysplasia of the hip This offers a biological explanation for why DDH is so much more common in girls: their hip ligaments may loosen more in response to maternal relaxin, allowing the femoral head to slip out of a shallow socket more easily.
Screening Your Baby’s Hips
In most countries, newborns are checked for hip instability with a simple physical exam in the first days of life, using maneuvers that gently test whether the hip can be displaced or relocated. Ultrasound is used selectively, usually for babies with risk factors like breech presentation, family history, or an equivocal physical exam. A decision analysis comparing screening strategies found that physical examination of all newborns combined with selective ultrasound yielded the best expected outcome for long-term hip health, slightly outperforming both universal ultrasound and no screening at all.11PubMed Central. To Screen or Not to Screen? A Decision Analysis of the Utility of Screening for Developmental Dysplasia of the Hip
If your baby has any risk factors for DDH, make sure the hip check at birth is documented and that follow-up ultrasound is arranged if there is any doubt. Early detection matters enormously for treatment outcomes.
How Infant DDH Is Treated
When DDH is caught early, treatment is usually non-surgical. The Pavlik harness, a soft brace that holds an infant’s hips in a flexed, open position, is the standard first-line approach for babies under about six months of age. Success depends on the severity of the dysplasia, the age when treatment begins, and whether one or both hips are affected. In one study, about two-thirds of treated hips responded well to the harness alone.12PubMed Central. Indicators of successful use of the Pavlik harness in infants with developmental dysplasia of the hip The younger the baby is at the start of treatment, the better the odds.
When bracing fails or when the condition is caught later, surgery becomes necessary. For children diagnosed between roughly 18 months and five years, open reduction of the hip combined with a pelvic osteotomy (a reshaping of the bone around the socket) is the standard approach. Long-term follow-up data stretching out 45 years after this procedure shows durable results, though outcomes are better the younger the child is at surgery.13Journal of Bone and Joint Surgery. Outcome at Forty-five Years After Open Reduction and Innominate Osteotomy for Late-Presenting Developmental Dislocation of the Hip A large retrospective review of over 700 hips treated with open reduction, either alone or combined with osteotomy, confirmed that most children require the combined approach rather than open reduction alone.14PubMed Central. Outcomes following open reduction for late-presenting developmental dysplasia of the hip
For children diagnosed even later, after age four, single-stage procedures that combine open reduction with femoral shortening and pelvic osteotomy can still produce good results, though the surgery is more complex. One series reported performing these combined procedures at a mean age of about seven and a half years.15Kocatepe Tıp Dergisi. How Does Initial Surgery Age Affect the Radiological Results of Single-Stage Open Reduction, Femoral Shortening, and Salter’s Osteotomy in Patients Over the Age of Four with Developmental Hip Dysplasia? The takeaway is straightforward: earlier detection means simpler, less invasive treatment with better long-term outcomes.
How You Handle Your Baby Matters Too
One of the more actionable findings in DDH research is that what happens after birth, not just during it, influences hip development. Cultures that traditionally swaddle infants tightly with the legs straight and pressed together have historically shown higher rates of DDH, while cultures that carry babies straddling the parent’s hip (legs apart and flexed) have lower rates. The evidence on this is consistent and has accumulated over decades.
A review of the literature found overwhelming evidence linking tight, legs-together swaddling with increased DDH incidence. On the other hand, “hip-safe” swaddling that wraps the upper body snugly but leaves the legs free to flex and spread, along with baby carriers that support the thighs in an open frog-leg position, promotes healthy hip development.16PubMed Central. Developmental Dysplasia of Hip and Post-natal Positioning: Role of Swaddling and Baby-Wearing If your baby has any risk factors for DDH, or even if they do not, avoiding the straight-legged swaddle is one of the simplest protective steps you can take.
The Evolutionary Backdrop
It can feel frustrating that human hips seem so prone to trouble around childbirth, and the reason traces back millions of years. The human pelvis is an evolutionary compromise between two competing demands: a birth canal wide enough to deliver a large-brained baby and a pelvic structure narrow and stable enough for efficient upright walking. For a long time, researchers assumed the pelvis could not simply evolve to be wider because that would ruin bipedal gait. More recent work suggests the real constraint may be elsewhere: a wider pelvis would likely compromise the pelvic floor, increasing the risk of incontinence and organ prolapse.17American Journal of Obstetrics and Gynecology. Evolution of the human birth canal The result is a pelvis that is just barely adequate for both jobs, which leaves the hip joints of both mothers and babies operating closer to the edge of stability than almost any other primate. That evolutionary tightrope is part of why hip dysplasia remains as common as it is, and why the stresses of pregnancy and birth can tip a borderline joint into trouble.