Living at higher altitudes increases the risk of difficult childbirth for pregnant women. Medical research confirms that abnormalities in any of the three key factors of labor—labor force, birth canal, or fetus—can lead to difficult delivery. Researchers from the Japanese Public Health Association recently discovered through surveys that women residing in high-rise buildings exhibit a higher incidence of abnormal deliveries.
Using maternal and infant registry data from 1,000 women, researchers analyzed living conditions, birth weight, and delivery complications. They found that women residing in high-rise buildings had a significantly higher rate of abnormal deliveries—including cesarean sections and induced labor—accounting for 17.5% of all cases.
Moreover, the incidence of difficult labor increased with higher floor levels: 20% for those on floors 1–2, 25.2% for floors 3–5, and 27% for floors 6 and above. Significant differences also emerged in infant birth weight: among mothers on floors 1–2, 20.5% had infants weighing under 3,500 grams, while 19.7% had infants over 3,500 grams.
For mothers residing on the 3rd floor or higher, 21.9% of infants weighed under 3500 grams at birth, while 42.9% weighed over 3500 grams. Researchers suggest that as residential buildings grow taller, inconveniences like climbing stairs become more pronounced. Pregnant women living higher up tend to have fewer opportunities for outdoor activity.Insufficient exercise makes mothers prone to abnormal labor contractions during delivery. Weak uterine contractions fail to effectively dilate the cervix and descend the fetus, prolonging labor and ultimately leading to difficult delivery.
Additionally, lack of exercise in pregnant women can result in macrosomia (excessively large fetus), further increasing the risk of difficult delivery. Therefore, pregnant women residing in high-rise buildings should engage in appropriate exercise to prevent difficult delivery.
Four Key Factors Contributing to Difficult Delivery
Keyword 1: Labor Forces
What are labor forces?
Labor forces refer to the power expelling the fetus and its associated structures from the uterus. This encompasses three primary forces: uterine contractile force (uterine contractions), abdominal wall and diaphragm contraction force (abdominal pressure) after full cervical dilation, and levator ani muscle contraction force. These three forces collectively form labor forces.Therefore, during labor, medical staff often use phrases like "regular contractions," "irregular contractions," "too short duration of contractions," "patient not pushing effectively," or "insufficient pushing effort" to describe whether labor forces are normal or abnormal.
Among these three forces, uterine contractions are paramount, playing a pivotal role in determining whether cervical dilation progresses normally from the onset of contractions to full dilation.
Uterine contractility
is the primary labor force after the onset of labor, persisting throughout the entire delivery process.The onset of uterine contractions does not guarantee uncomplicated delivery. The adequacy and effectiveness of uterine contractions must be assessed based on several factors: the rhythm, duration, and interval of contractions; the intensity of contractions; and the descent of the fetal presenting part.
Each contraction begins weakly, intensifies over time, maintains its peak intensity for a period, then gradually weakens until it subsides. This subsiding phase is called the "interval," representing the time between contractions. During the interval, the uterine muscles relax, pain ceases, and mobility returns to normal. This pattern of "labor pains" repeats until the entire delivery process concludes.
Regular contractions typically occur every 4–5 minutes, lasting about 30 seconds each. As labor progresses, the intervals between contractions gradually shorten while their duration increases. By the time the cervix is fully dilated, contractions may last up to 60 seconds with intervals of 1–2 minutes.
The intensity of uterine contractions gradually increases throughout labor, making the intervals between contractions even more critical. Only rhythmic, intermittent, and sufficiently strong contractions can ensure a smooth delivery and fetal safety.
Any disruption to the regularity of these uterine contractions significantly increases the risk of dystocia.
Abdominal Wall Muscles and Diaphragm Contraction
These muscular forces provide crucial auxiliary support for fetal expulsion after full cervical dilation. This explains why medical staff often instruct mothers to bear down and push during delivery—increasing intra-abdominal pressure facilitates the expulsion of both the fetus and placenta.
Key Term 2: Birth Canal
The birth canal is the pathway through which the fetus is delivered, commonly referred to as the pelvis. It comprises the bony pelvis and the soft birth canal. The term "pelvis" typically denotes the bony pelvis. The size and shape of the pelvis are closely related to the delivery process.
The pelvis is further divided into three planes: the inlet, the middle pelvic plane, and the outlet plane (the outlet itself is subdivided into two distinct sagittal planes). Each plane is further categorized into longitudinal and transverse dimensions, or anterior and posterior diameters. While this may sound complex, it's important to note that the vast majority of Chinese women have normal pelvic structures, consistent with the typical female pelvis.
The primary factors causing difficult labor are rarely abnormal pelvic measurements. Instead, it's often due to a large or oversized fetus, abnormal fetal head position, or abnormal fetal presentation. These conditions make an otherwise normal pelvis appear "abnormal or narrow," leading to delivery difficulties—difficult labor.
Keyword 3: Fetus
Fetal Size and Position: Whether a fetus can pass through the birth canal smoothly depends on its size, position, and the presence of any abnormalities.
During labor, fetal size is a key determinant of delivery difficulty. An excessively large fetus (over 4000 grams) resulting in a large cephalic diameter can cause relative pelvic narrowing and obstructed labor, even with normal pelvic measurements, due to cephalopelvic disproportion. Conversely, a fetus of average weight may still cause obstructed labor if the fetal head is malpositioned.
Clinically, it is common to encounter cases where the fetal head fails to descend into the pelvis near term or during labor, remaining in a floating position. Such situations warrant vigilance for cephalopelvic disproportion and potential delivery complications.
Fetal abnormalities: Developmental anomalies in certain fetal parts, such as hydrocephalus or conjoined twins, may cause difficult labor due to an oversized fetal head or body unable to pass through the birth canal.
Keyword 4: Psychological
It is crucial to recognize that factors influencing labor extend beyond uterine contractions, birth canal, and the fetus to include the mother's psychological state.
A significant number of expectant mothers (especially first-time mothers) develop fear and anxiety after hearing negative accounts of childbirth from relatives, friends, or neighbors, leading them to refuse normal vaginal delivery.
Some mothers dread the prospect of "enduring twice the hardship and suffering" if a trial of labor fails.
Others fear the fetus may not be of the desired gender.Consequently, they often remain in a state of anxiety, unease, and fear. These emotional shifts trigger physiological changes: accelerated heart rate, rapid breathing, inadequate gas exchange, uterine hypoxia leading to weak contractions, prolonged labor, and excessive maternal exhaustion. Simultaneously, maternal endocrine changes, elevated blood pressure, fetal ischemia and hypoxia, decreased fetal heart rate, and fetal distress may occur.
The unfamiliar and isolated environment of the labor ward, coupled with the frequent commotion and noise in the delivery room, can heighten a mother's fear and anxiety, leading to complications in labor.
A "prolonged" labor process may cause the mother to lose patience, confidence, or even the courage to give birth, resulting in difficult delivery or abandonment of the birthing process.
Expectant mothers need not fear difficult labor—it can be prevented.
1. Maintain balanced nutrition to avoid excessive weight gain causing fetal macrosomia.
Fetal macrosomia is now the primary cause of difficult labor. With improved living standards and the prevalence of only children, families often dote excessively on expectant mothers. This leads to over-supplementation, resulting in maternal obesity and fetal macrosomia, which significantly complicates delivery.
During pregnancy, weight gain should be controlled within the reasonable range of 10–14 kilograms. If the baby's head is too large (bpd exceeding 10 cm), delivery will be difficult. Once bpd exceeds 10.5 cm, vaginal delivery becomes impossible. Therefore, maintaining balanced nutrition throughout pregnancy to ensure the fetus receives necessary nutrients is sufficient.
II. Regular prenatal checkups reduce or eliminate factors causing difficult labor in both mother and fetus.
Prenatal checkups serve dual purposes: screening the mother for related diseases and monitoring fetal development. They provide essential oversight throughout pregnancy. For instance, breech presentation is a major cause of difficult labor. Early detection through checkups allows pregnant women to follow medical advice and actively cooperate in adjusting fetal position, typically enabling normal delivery.Failing to undergo prenatal checkups and discovering an abnormal fetal position only during labor poses significant risks to both the smooth delivery process and the health of the mother and baby. Therefore, pregnant women should attend regular checkups to identify and address issues early.
III. Prioritize exercise to support delivery.