Maternal grandmothers concentrate on offspring survival, whereas paternal grandmothers increase birth rates.Some believe variations on the mother, or grandmother effect fail to explain longevity with continued spermatogenesis in males (oldest verified paternity is 94 years, 35 years beyond the oldest documented birth attributed to females). Notably, the survival time past menopause is roughly the same as the maturation time for a human child. That a mothers presence could aid in the survival of a developing child, while an unidentified fathers absence might not have affected survival, could explain the paternal fertility near the end of the fathers lifespan. A man with no certainty of which children are his may merely attempt to father additional children, with support of existing children present but small. Note the existence of partible paternity supporting this. Some argue that the mother and grandmother hypotheses fail to explain the detrimental effects of losing ovarian follicular activity, such as osteoporosis, osteoarthritis, Alzheimers disease and coronary artery disease.The theories discussed above assume that evolution directly selected for menopause. Another theory states that menopause is the byproduct of the evolutionary selection for follicular atresia, a factor that causes menopause. Menopause results from having too few ovarian follicles to produce enough estrogen to maintain the ovarian-pituitary-hypothalamic loop, which results in the cessation of menses and the beginning of menopause. Human females are born with approximately a million oocytes, and approximately 400 oocytes are lost to ovulation throughout life.
A cephalohaematoma is a hemorrhage of blood between the skull and the periosteum of any age human, including a newborn baby secondary to rupture of blood vessels crossing the periosteum. Because the swelling is subperiosteal, its boundaries are limited by the individual bones, in contrast to a caput succedaneum. Symptoms and signs
Swelling appears after 2-3 days after birth. If severe the child may develop jaundice, anemia or hypotension. In some cases it may be an indication of a linear skull fracture or be at risk of an infection leading to osteomyelitis or meningitis. The swelling of a cephalohematoma takes weeks to resolve as the blood clot is slowly absorbed from the periphery towards the centre. In time the swelling hardens (calcification) leaving a relatively softer centre so that it appears as a depressed fracture. Cephalohematoma should be distinguished from another scalp bleeding called subgaleal hemorrhage (also called subaponeurotic hemorrhage), which is blood between the scalp and skull bone (above the periosteum) and is more extensive. It is more prone to complications, especially anemia and bruising. Causes
The usual causes of a cephalohematoma are a prolonged second stage of labor or instrumental delivery, particularly forceps delivery. Ventouse application does not increase the incidence of cephalhematoma. Vitamin C deficiency has been reported to possibly be associated with development of cephalhematomas. Management
Skull x-ray or CT scanning is used if neurological symptoms appear. These measurements are also used if concomitant depressed skull fracture is a possibility. Usual management is mainly observation.